A dry dock is a structured area where the construction, repairs, and maintenance of merchant vessels and boats are carried out. This unique construction or arrangement allows water to be filled up in an area, also known as a lock, so vessels can be manoeuvred in and out of the area.

Once the vessel enters the dry dock, the gates are closed, and the seawater is drained out so that the hull and other parts of the ship, which have been exposed to seawater for a long time, are exposed for maintenance and repair work.

Dry Dock Survey

As per SOLAS requirements, all Merchant vessels require a complete survey of the hull in a dry dock twice within a 5-year period and an intermediate survey within 36 months at the earliest.

This includes maintenance of the hull, propeller, rudder, etc. and other parts which are immersed in water and are generally inaccessible by staff when the ship is sailing

For a passenger vessel, the bottom is to be inspected annually. Two such inspections in a period of five years must be carried out in dry dock, and the maximum interval between these inspections should be three years.

Types of Dry Dock

Different types of dry docks are used for repairing and cleaning a ship. The main ones are:

1. Graving dock
2. Floating dock
3. Marine Rail Dock
4. Shiplifts
5. Marine mobile lifts

Among these, the marine mobile lifts and ship lifts are mainly used for small vessels such as recreational yachts, tugs, pilot boats, etc.

Nowadays, there are mainly two types of dry dock procedures from the above list that are used for seagoing vessels:

1) Graving Dry Dock

This type of dry dock is normally constructed on land near coastal waters. It is rectangular and made of solid concrete, with blocks, walls, and gates. The vessel is shifted inside the dry dock and rested on the blocks. After the ship is in the required position, the gate is closed, and water is removed.

Related Read: Understanding Ship Stability During Dry Dock

In the past, the graving dry docks were constructed using stones and timber. Now, a steel and concrete enclosure is used, and a heavy steel gate is used to seal the dock to stop water ingress once the ship is standing on the blocks.

The gates can be in two parts, with each hinged to the sides and hydraulically operated, or one solid steel structure supported on a roller over the track, which can be retracted inside the dry dock walls when opening the gate.

Advantages of Graving Dry Dock

1. It can accommodate vessels of bigger sizes when compared to other dry docking systems.
2. It is cheaper to dry-docking a vessel of a similar size to other types.
3. The graving dry dock can perform retrofitting, modification, etc., which is challenging in other types.
4. Due to its location near the land, the graving dock is easily accessible for the supply of spares, machinery, and services.
5. New advanced graving docks have welding, hot-work and other workshops inside the dock on an elevated surface (above the water surface when the dock is filled), giving quick access and workflow in the dock.
6. Retractable ramps in new graving docks make it easy to supply spare machinery and save a lot of time and manpower to transfer them inside the dock.
7. A bigger graving dock can be used to repair more than two ships at a time, and some modern graving docks have two gates at both ends, making it easier to repair and re-float the vessel independently.

Disadvantages of Graving Dry Dock

• When re-flooding the dry dock, all the machinery and equipment needs to be taken out from the dock, which takes time.
• The maintenance cost of the graving dock increases as per the age of the dock and becomes very high.
• Any problem with the dock gate will make the whole dock non-operational

• The docking and undocking process in the graving dock takes time compared to other types
• If the dock holds multiple ships for repair, the complete operation needs to be stopped if any one of the vessels needs to be taken out of the dry dock as it will require filling of water for refloating

2) Floating Dry Dock

A floating dock is in the form of a “U” structure, mainly used in salvage to carry ships that have met with an accident and are damaged to an extent that has made them unable to sail further to a coastal dock.

However, many regular sea-going, small, and mid-size vessels are now dry docking in floating docks. Several “U” type floating docks can be joined to carry a large vessel.

The ship is brought near the channel where the floating dry dock will partly submerge itself, and the ship slides inside the dock.

Once the ship is in position, the floating dock is de-ballasted to drain the water from its hollow floors and walls, which support the vessel on the blocks arranged on the dock’s floor.

A valve is provided that can be opened to fill up the chambers with water and immerse the dock so that the ship can sail out.

The water is pumped out of the chamber, allowing the dry dock to rise, exposing the underwater area of the ship for maintenance or carrying out the ship repairs. 

Related Read: What is Ballasting and De-ballasting?

The floating dry dock is usually built using steel framing similar to that of seagoing vessels, with ballast tanks provided on the sides and bottom to raise and lower the dock.

Floating dry docks are commonly operated in sheltered harbours, where there are no waves or natural tidal activities.

Advantages of a Floating Dry Dock

1. They can be propelled to the location of a salvage vessel near the harbour
2. They are cheaper to maintain as compared to graving docks and can get a higher resalable return
3. They can be installed near or away from the shore inside the harbour, making them a portable and space-saving structure without taking space of the shore facility
4. The complete floating dry dock can be aft or forward trim by ballasting the dock, which further assists the ship or the damaged vessel which cannot be given a trim
5. Additional mooring equipment is needed for the floating dry dock to make it stable
6. The floating dry dock can be altered and increased in size in all dimensions by extensive retrofitting/ rebuilding
7. They can also be split into two different floating docks independent of each other

Disadvantages of Floating Dock

• The supply of store, equipment, and manpower is usually done from one access point gangway, which makes the operation slow.
• The maintenance cost of a floating dry dock is similar to that of a ship, as the hull is submerged in saltwater.
• The floating dry dock operation will be affected if there are tides or during windy weather.
• When re-flooding the dock, all the machinery and equipment needs are to be removed, which takes time.

Blocks Of Dry Dock

The blocks inside the dry dock play a critical role in taking the ship’s load and distributing it among the blocks placed below the keel plates. Every ship has a docking manual that will provide a guide block plan approved by the Ship Classification Society.

The shipmaster/ chief officer and the dry dock master must understand the blocking plan for the particular vessel and how the ship will behave under load when resting on the blocks, including various factors that can affect the load a block takes.

The blocks are usually constructed from one material so that their stiffness is similar. If the blocks are built from different materials, the force exerted on the blocks with a smaller elasticity module will squeeze them more than the stiffer block. This can lead to damage to the block or the ship’s hull, as the force distribution will be uneven.

The most common materials used for the blocks are:

• Concrete with steel
• Timber blocks
• Timber on top and concrete at the bottom

When a timber block is added to a keel track built of blocks with concrete or steel bases, the timber block will take a much smaller load than the others.

Apart from the keel blocks, side blocks are also arranged to support the ship. They are less stiffer than the keel blocks as a stiffer side block will overload the vessel and may damage the structure. The height of the slide blocks is usually similar or more than that of the keel blocks.

Important factors which affect the loading on the dry docking blocks are:

• The initial height of the block: The block’s height is a critical factor, as the load on the individual block will be determined by the load shared by all the other blocks. If the placement and height of the blocks are according to the ship’s hull, the load distribution will be even.
• The contact area of the block: The contact area of the block with the ship’s hull determines the load distributed on the block. If the contact area of the block is smaller in size, this means the load exerted on this block will be lesser than that with a larger contact area.
• The material of the block: As stated earlier, different materials will react differently to the load exerted by the ship. Hence, the material of the block used for the keel block and the side block plays an important role in aligning the ship in the dry dock.
• Placement of the block: The blocks in the dry dock need to be arranged according to the ship’s docking plan. Many types of equipment and parts can get damaged if the block position is not altered. For example, echo sounders, anodes, etc., the blocks need to be removed so that these equipment tools have space to settle once the ship rests on them.

Choosing A Type of Dry Dock

The criteria to select a type of dry dock  for a ship depends on the following factors: 

• The size of the vessel: The graving dock accommodates larger sizes than any other type. If the shipowner/ manager has to dry dock a large oil tanker, they will go to the graving dock. The Marine railway type can be used if the vessel is about 10000 tonnes. If a boat or small yacht of up to 250 tonnes needs repair in the dock, a mobile marine lift can be used.
• The condition of the vessel: If the vessel propulsion plant is not working or some damages can make a ship immobilized, floating docks are commonly used in such a condition
• Types of repair: The choice of dry dock type also depends on the type of repair the ship wants to undergo. For the regular scheduled dry dock, a floating dock can be selected; however, if there is major retrofitting or massive parts/ machine fitting is required, the graving dock is chosen as they are usually located near the shipyard and it is easy to move the material from land to dock as compare to the floating dock.
• Schedule of the Vessel: The location and the type of the dry dock will be decided as per the current schedule of the vessel and how easy it is for the ship to reach the dock after unloading all the cargo to the last port of call
• Budget: The most critical factor in selecting the type of dry dock is the budget allotted to the ship

Related Read: How Cost Estimation is done for Ship’s Dry Dock?

Requirements for Dry Docking

Stability is the most important requirement for getting a ship safely into a dry dock. The three important parameters which must be ensured before entering the dry dock are:

1) Adequate Initial GM:

When the ship touches the blocks, a reaction at the point of contact raises the centre of gravity “G” and reduces the metacentric height “G.M.” so that an adequate initial metacentric height is required to compensate for this.

2) Vessel to be Upright:

While entering the dock, the vessel must be upright, meaning there should be no port or starboard list when the ship touches the blocks. If the point of contact of the ship and keel blocks is outside the centre line of a vessel, it may force the ship to tip over.

3) Small or Moderate Trim Aft:

When making the ship’s keel sit on the keel block, a moderate trim aft is usually kept. As the water level in the dock lowers, the slight trim allows the stern and bow to ascend in tandem rather than simultaneously, which will reduce the load and pressure on a vessel’s hull and keel.

Related Read: 10 Types of Dry Dock Accidents That Can Occur in Ship’s Engine Room

Dry Dock Procedure

Once the ship manager selects the type of dry dock, the next step is to prepare the ship to enter the dry dock and carefully place the ship’s keel on the blocks provided on the dry dock floor. Some important points to note are:

• Make sure the ship is prepared to enter the dry dock by having the least ballast and no cargo carried on board
• If the floating dock is used, the ship’s movement will depend on the docking master’s requirements and the vessel’s condition. If the vessel is immobilized due to an accident, the floating dock will move towards it, and if the vessel is functioning correctly, it may propel inside the dock.
• Once the ship enters the dry dock, it is moored to the dock
• The docking master will inform the ship’s crew beforehand about the trim requirement they must maintain.
• Before emptying the dock, the ship and dock master must ensure that equipment like an echo-sounder or log sensor does not hit any blocks and is clear of any obstruction. For this, divers are sent to check that all such equipment is precise of the blocks
• The dock master will give the order to pump the water out from the dock, and slowly, the ship will sit on the keel  blocks
• The docking master and the ship’s crew must ensure the point of contact of the ship and keel blocks does not lie outside the centre line of a vessel as it may lead to the tumbling of the ship
• Once the ship sits on the dock, the cleaning and repairing process starts 

Related Read: Dry Docking of Ships – Understanding Stability And Docking Plan

Duties of Ship Crew Members During Dry Docking

While dry-docking the ship, the duty of the ship’s crew (under the guidance of the chief engineer and chief officer) will be:

• To keep the ship at minimum ballast condition
• To keep the aft trim as requested by the dockmaster
• To ensure the vessel is moored by assisting the dock crew once the ship comes inside the dry dock
• To keep a check on the stability of the ship while the water is lowered in the dock
• Once the ship is sitting on the blocks, the ship’s crew will pump out the ballast
• To prepare the vessel to connect to the shore power
• Once the dry dock water is pumped out, de-ballast tanks using gravity
• Remove the drain plugs from the bottom of the ship for various tanks

Related Read:

• Checks to Perform on Ship before Coming out of the Dry Dock
• What is Extended Dry-Docking of Ships?

Drydocking is one operation that allows the ship’s crew to learn areas that cannot be explored when the ship is sailing.

It also helps the ship manager to assess the condition of the ship’s hull and the machinery which are not accessible when the ship is in water.

Bringing the ship to the dry dock is a team effort between the ship’s crew and dry dock personnel. Proper communication is the key to safely laying the ship’s keel on the keel blocks.

Disclaimer: The authors’ views expressed in this article do not necessarily reflect the views of Marine Insight. Data and charts, if used, in the article have been sourced from available information and have not been authenticated by any statutory authority. The author and Marine Insight do not claim it to be accurate nor accept any responsibility for the same. The views constitute only the opinions and do not constitute any guidelines or recommendation on any course of action to be followed by the reader.

The article or images cannot be reproduced, copied, shared or used in any form without the permission of the author and Marine Insight.

The Ultimate Guide to Dry Docks: Types, Functions, and Essential Requirements appeared first on Marine Insight - The Maritime Industry Guide

When at sea, use of marine binoculars is necessary for enhancing the safety of the vessel. Though there is no specific regulation in SOLAS on the number of binoculars present on vessels, it is important that all vessels are equipment with best marine binoculars.

As a mariner, it is important to know about the binocular (and its features) you are using at sea to ensure you are having the correct one and in case there is a need of upgrade.

What you should know when using or buying a Marine Binocular?

There are usually five important things that you must know when it comes to knowing your binocular. They are:

1. Magnification and Lens Diameter
2. Focus
3. Field of view
4. Waterproof/Fog proof

Most commonly used marine binoculars are of 7×50 type. This means that the binocular has a magnification of 7x and the objective lens diameter of 50 mm.

If you want to purchase the best marine binocular, this is the first thing you will look at – the magnification and the lens diameter.

Let’s understand each of the above features.

Magnification and lens diameter:

Binoculars are categorised in numbers – 7×50, 7×35, 8×25 etc. , where the first digit is the magnification and the second is the diameter of the lens.

At sea, it is obvious that higher the magnification, greater the information we will be able to gather through our eyes.

However, it is to note that, as the magnification increases, the harder it gets to keep an object in view, making it blurry as the brightness reduces. To prevent the reduction in brightness, higher lens are required to increase the brightness of the image. As the size of the lens increases, so does the size of the camera, making it bulky and uncomfortable to use.

Moreover, the distorted and blurry image is further spoilt by shaky hands and swaying movement of the vessel.

Therefore, it is advisable that marine binoculars have a conservative magnification of not more than 7x with objective lens diameter of 50mm.

Focus :

Center focus or Individual Focus

Marine binoculars usually come in two variants – centre focus and individual focus or fixed focus .

In centre focus binoculars, there is a knob at the centre which simultaneously changes focus on both eyepieces. This is a traditional type of binocular and is helpful if you would be sharing your binocular with the rest of the crew (As everyone can adjust focus according to their need).

Center focusing is the most common type of binoculars available in the market.

However, most of the marine binoculars are of individual focus variant.

Advantages:

– Ergonomically easiest- Knob is easy to use
– Focus really close objects

– They can be used for even the shortest distances.

– They have better resolutions as well
– Good for those with eye glasses ( have movable eye cups)

Disadvantages:

– Difficult to waterproof them. – Have difficulty with watertightness and internal fogging

– It takes time to focus every time it is used

Individual focus (Fixed focus):

In individual focus marine binoculars, focuses of each eyepieces can be separately managed.

This prevents the need of adjusting the focus every time the binocular needs to be used. This saves a lot to time, especially in emergencies at sea.

Advantages 

– Focus only once. There is no need to focus again. The eyes do the focusing for you even with varying distances.
– In low light situations, it is difficult to focus in center focus binoculars whereas in individual focus came, as the focus was already done before, it is easy to focus on the object.
– Most of them are waterproof (more easier to make them waterproof)

Disadvantages

– Difficult for close focusing
– Difficult to use for those with glasses. Most have eye cups that are not adjustable.

Field of view:

Field of view is typically the measurement of width in feet or meters from a fixed point. It describes the image visible horizontally when looking through the binocular without moving the same.

Field of view is measured in feet at a distance 1000 yards or meters. Each degree of view is equal to 52.5 feet at 1000 yards.

It is to note that the field of view and magnification are inversely proportional. Which means if magnification increases (with smaller objective diameter), the field of view of the marine binocular decreases and thus narrower will be the image.

For marine binoculars, it is important to have the widest field of view.

Eye relief:

Another thing that needs to keep in mind is the eye relief of the marine binocular. It is the distance between the eye and the ocular lens (eyepiece). It is important to maintain the right distance to view a sharp image.

Usually, eyecups are installed on the eyepieces so that the viewer’s eyes are at a proper distance from the eyepieces.

Those wearing glasses, needs to be careful as the eyepieces will be positioned past the eye relief distance, which will give a blurry image and reduce the image quality.

Though, almost all marine binoculars come with adjustable eyecups, which can be pushed back inside to allow placing the eyeglass lens closer to the ocular lens and maintain the eye relief.

Waterproof/Fog proof:

Considering the type of harsh environment marine binoculars are used in, they must be waterproof and resistant to fog.

Waterproofing in binoculars is done by sealing all the opening with O-rings. This helps in keeping dust and moisture from entering the binocular body.

Almost all waterproof binoculars are filled with dry nitrogen gas at a pressure higher than the normal atmospheric pressure. This positive pressure prevents lower pressure outside air or moisture from entering the binocular. Also, nitrogen gas cannot hold any moisture, and therefore the water cannot get inside the binocular body. Though waterproof binoculars are internally fog-proof, moisture can still condense on the outside of the lens.

However, it is to note that just because a binocular is termed as waterproof, it cannot withstand full submersion in water. Some superior binoculars do have waterproof feature until certain submersion depth and a specific amount of time, which is specified on the binocular.

Do remember that technically, all fog-proof binoculars are waterproof. However, not all waterproof binoculars need to be fog-proof.

Additional features:

Nowadays, several high-end marine binoculars come with more advanced features which might make your life easier at sea.

Some of these features you should look out for are:

Floating strap:

Some of the marine binoculars come with a floating strap whereas sometimes you might have to buy it. If you are investing a good amount of money in a marine binocular, it is important that you invest a few extra in an adjustable floating strap which would protect your binocular if it goes overboard.

If your marine binocular is waterproof, that’s good, but then if your optics go overboard in deep sea, then that would be the last time you will be seeing them.

Floating straps are made with high buoyancy materials which prevents them from floating should they fall in water.

Compasses 

A few marine binoculars available in the market also come with a built-in compass. They give a superimposed compass just below the image while viewing through the binocular. This comes very handy while observing any vessel at a distance and knows its direction. The compass feature is highly useful from safety point of view of the vessel.

Some marine binoculars also come with digital compasses and the system is illuminated as well.

Rangefinder reticule 

Rangefinder is an added feature which is provided in many marine binoculars. This binoculars come with an integrated infrared laser system which helps in measuring a distance of a vessel or object from the binocular. They are very handy at sea, especially in emergency situations.

The distance is generally displayed in meters or feet and the readout is visible directly in the eyepiece.

Some marine binoculars also come with inclinometers.

Image stabilisation

Image stabilisation technology first came in digital cameras. Several major companies that make marine binoculars incorporated this technology in binoculars, which helps in compensating the observer’s movement or swaying of the vessel.

Marine binoculars with image stabilisation technology are fitted with a gyroscope which helps in reducing movement in high powered binoculars.

Best Marine Binocular 

Let’s take a look at the top 10 marine binoculars in the market today.

1. Bushnell Marine 7x50 Waterproof Binocular

Bushnell is one of the leading quality marine binocular makers in the market today. Most of the marine binoculars you see on ships will of Bushnell brand. 

Corrosion resistant and waterproof, Bushnell 7×50 marine binocular is specifically made for harsh environment condition. This durable individual focus, fog free binocular comes with non-skid rubber armour which is makes it very handy and comfortable to hold. 

The Porro prism system with Bak-4 prism glass offers the best clarity and wide range which is suitable for open waters.

At the particular price range this is the best value for money marine binocular in the market today. 

Check latest price

Pros:

• 100% Waterproof and durable
• Study HD Quality
• Wide Field Of View
• Non-slip, non-skid rubber armor

Cons:

• No image stabilisation
• Heavy and bulky

Check out customer reviews on amazon

2. Steiner 8x30 Military-Marine Binocular

The 8×30 Steiner 2033 is the perfect companion for outdoor activities. The 8x magnification offers clear and sharp image with a wide field of view.

Steiner marine binoculars are famous for their toughness and Steiner 2033 is no less with its rugged polycarbonate body, along with waterproof and fog resistant features.

The Steiner 8×30 comes with floating prism technology which uses flexible silicone lens mount to absorb severe impact and shock.

Most importantly, it has the auto-focus feature which helps to keep everything in focus from 20 yards and beyond without the need of constant focusing.

Check latest price

Pros:

• Extremely tough and durable
• Auto-focus
• Shock-proof
• Light weight and easy to handle

Cons:

• Value for money
• Not 100% waterproof
• No range finder reticle or compass

Read customer reviews here

3. BARSK Deep Sea 7x50 Waterproof Floating Binocular

BARSKA Deep Sea Waterproof Floating Binoculars is the best thing that you can get at that price.

With internal rangefinder and compass, this water proof and fog proof marine binoculars are meant for all weather conditions. Moreover, they float on water in case gone overboard.

The 7×50 Deep Sea Binoculars have BAK-4 prism which provides clarity and high contrast images.

Check latest price

Pros:

• Floating and water proof
• Rangefinder
• Compass
• Value for money
• Sturdy and non-slip design

Cons:

• Optical range finder Not Laser
• Bulky

Read customer reviews here

4. Steiner 575 Marine 7x50 Binoculars

Steiner 575 7×50 binoculars are specially made for marine activities. It also comes with auto-focus and floating prism system, providing added protection and ease-of-use.

Steiner 7×50 marine binoculars are also fog-resistant and waterproof to withstand the toughest conditions at sea.

The light and durable polycarbonate body can withstand great impact, providing toughness that comes with Steiner brand.

Check latest price

Pros:

• Tough and durable
• Comes with web strap and rain and spray guard
• Waterproof and shockproof housing

Cons:

• No built in compass
• Bulky

Read more customer reviews here

5. Bushnell 8x42 H2O Waterproof/Fogproof Porro Prism Binocular

This is the best and cheapest option you will find if you are looking for waterproof binoculars for marine use.

The Bushnell 8×42 H2O binoculars are waterproof and fog proof. They come with a large centre-focus know which helps in easy adjustment.

It has a sturdy non-slip rubber armour which can easily absorb shocks and provide better grip.

Check latest price

Pros:

• Waterproof and fogproof
• Value for money
• Rubber grip and neck strap

Cons:

• Heavy and bulky
• No compass and rangefinder scale

Read customer review here

6. Hooway 7x50 Waterproof Fogproof Military Marine Binocular

The Hooway 7×50 marine binoculars have Porro prism system which provides a wide field of view, perfect for using at sea.

It comes with anti-slippery rubber body with firm grip and shock absorption feature.

The marine binocular is completely waterproof and fog proof and can float in water.

It comes with a tripod adapter fitting for tripod mounting.

Check latest price

Pros:

• Compass and rangefinder
• Waterproof and fogproof
• Sturdy and robust

Cons:

• Material not that sturdy
• Optical range finder not laser
• You need to know the height of the object to measure the distance through rangefinder

Read customer reviews here

7. Fujinon Mariner 7x50 WPC-XL Porro Prism Binocular

Check latest price

The Fujinon Mariner 7×50 is a 100% waterproof marine binocular which comes with compass and reticle display.

It feature in built LED light for low light conditions.

It comes with a floating neck strap which protects the binocular in case it ever go overboard.

Pros:

• Easy to handle
• Light weight
• Comes with Floating Strap
• Value for money

Cons:

• A bit bulky

Read customer reviews here

8. Aomekie 7X50 Marine Military Binoculars

Aomekie 7×50 marine binoculars are one of the best waterproof, fog proof and low light binoculars in the market. They come with hi-index BAK4 prism with anti-reflective coating, which improves image sharpness and reduces light reflection.

This floatable marine binoculars provide a waterproof capability at 1m depth for upto 30 mins.

They also have a rangefinder and compass which is illuminated for low-light conditions.

Check latest price

Pros:

• Easy to carry
• Waterproof and fog proof
• Illuminated compass and rangefinder
• Value for money

Cons:

• Not 100% Waterproof
• Battery operated illumination

Read customer reviews here

9. ESSLNB Marine Binoculars with Illuminated Compass Rangefinder 7X50

ESSLNB marine binoculars come with illuminated integrated rangefinder and compass.

They are floating, water proof and fog proof. However, do note that they are water proof until one meter depth and can float in water for 30 minutes if dropped in water.

The ESSLNB 7×50 comes with BAK-4 prism along with multi-coated green wideband film technology which reduces reflected right and distortion of image.

The non-slip rubber coating helps is better grip and handling.

Check latest price

Pros:

• Rangerfinder
• Compass
• Value for money
• Individual focus system
• Waterproof / Fog proof

Cons:

• No night vision
• Not 100% waterproof

Read customer review

10. USCAMEL 10x50 Marine Binoculars

USCAMEL 10×50 marine binoculars are one of the best value for money equipment you can find in that range.

With 10x magnification and 50mm large objective lens, the USCAMEL marine binocular gives bright images with very less stabilisation issues. It has individual eyepiece focus capability with autofocus system avoids need to refocus.

They come with foldable eyecups which makes it easier to use for people with glasses.

This marine binocular are waterproof and fog proof and comes with inbuilt rangefinder and compass.

Check latest price

Pros:

• Waterproof and floating
• Compass
• Rangefinder
• Value for money

Cons:

• Not very efficient at night
• A bit heavy

Read customer reviews

When you want to choose the best marine binocular for your voyage, there is no one fit for all solution. The one you buy at the end mainly depends on your requirements and budget. However, investing in a good marine binocular is surely a wise decision as far as safety of yourself and your vessel is concerned. 

Over to you..

Which according to you is the best marine binocular available in the market today?

Let’s know in the comments below. 

Disclaimer: The authors’ views expressed in this article do not necessarily reflect the views of Marine Insight. Data and charts, if used, in the article have been sourced from available information and have not been authenticated by any statutory authority. The author and Marine Insight do not claim it to be accurate nor accept any responsibility for the same. The views constitute only the opinions and do not constitute any guidelines or recommendation on any course of action to be followed by the reader.

This post may contain affiliate links, meaning we get a small commission if you decide to make a purchase through our links, at no additional cost to you. You can read our full disclaimer here.

The article or images cannot be reproduced, copied, shared or used in any form without the permission of the author and Marine Insight.

Top 10 Marine Binoculars for 2024 appeared first on Marine Insight - The Maritime Industry Guide

Dredging removes the deposits percolated underwater to clear the water pathway for ships to pass, creates adequate space to construct important bridges, dykes and dams and weeds out silt, intoxicants and pollutants from the bottom of the water.

Once the hoppers are full, the process is halted for a while, and the ship travels to the water disposal site, where the unwanted sediments are released through the bottom of the ship.

What is the Dredging Process?

It involves excavating naturally deposited sediments or artificial debris such as rocks, bottom sediments, construction debris, refuse, and plant or animal matter on the bottom of shallow seawater or freshwater.

The dredge operator lowers it to the side of the body of water or its bottom. The rotating cutter bar uses its sharp blades to loosen the sediment on the bottom, and it is sucked in using a submersible pump. Ultimately, disposal barges or dump scows empty the material at the disposal area.

In general terms, dredging implies digging up the gathered sediments from the seabed and disposing of them at another site.

The oldest known dredging activities are dredging for peat excavation and maintenance dredging. Maintenance Dredging is a broader term that includes clearing deposits and cleaning, widening or deepening a water body using a suction or scooping device (generally called a dredger).

Regular maintenance dredging is of enormous importance in coastal regions with sizeable tidal activity and in water bodies that are susceptible to becoming silted with sediments, sand and mud. The Lowlands of the Netherlands and Flanders are the best examples of regions requiring regular maintenance dredging.

For dredging, dredgers are used to remove the deposited sediments from an inlet creek, waterway or ocean floor.

The process is a blended essence of the following three independent elements: excavation, transportation of excavated material and then usage or proper disposal of dredged material.

When did Dredging Start?

With the beginning of civilization, commodities were transported by inland waterways and oceans. But this transportation depended on the ability of ships, which in turn largely depended on the water depth.

Silting, the natural phenomenon of deposition of silt and sediments over the sea bed, created a constant threat to the voyages of ships.

People started fighting the problem of siltation to ensure the safety of voyages. Still, due to a lack of equipment for removing siltation, they started manually digging the mud by hand, which was inefficient and limited to shallow waterways.

In the 15^th century, increased trade at seas necessitated the development of some bed scratchers such as “Zeeuwse Krabbelaar”, a primitive bed leveller. These bed levellers cum scratchers were used to pick the sediments and dispose of them. These dredgers developed from ancient mills to modern suction dredgers.

Mills was developed around 1575. These were a sort of dredging equipment used for digging in ports. Mills had a rotating chain connected with wooden boards, and these wooden boards dug up the mud.

At the primary stage of the development of mills, they were manually driven later. Steam engines powered them. Mills had gone obsolete in 1857 with the development of a suction dredger in the United States.

In 1867, a revolutionary development came with the evolution of the design of a suction dredger by a French engineer. He successfully used this suction dredger in dredging the Suez Canal. From then on, dredging by suction became more and more common.

Then came cutter suction dredgers and trailing suction hopper dredgers in the 19^th century. These are modern dredgers and can avail efficient dredging. These were so efficient that they allowed shipping and dredging simultaneously without hindering the traffic.

Recent dredging evolutions have optimised the dredging process as its primary focus rather than developing new dredgers. So, standardizations of dredgers and equipment and advancements in control and monitoring systems improved dredging greatly.

Importance of the Dredging Process

Dredging is an activity of enormous importance in the maritime industry. It serves the following purposes:

• It helps safer voyages by pacifying underwater traffic and maintaining proper bottom clearance.
• Dredging increases the depth of navigation channels, ports and berths, allowing for the free flow of maritime traffic.
• Sometimes, dredging is employed to extract ocean gems such as shellfish and molluscs. So, dredging can help in exploring excellent varieties of these sea creatures.
• Dredging is a primary requirement to channel the construction of a network of bridges, dams, or other civil engineering works in water. These are only proper dredging tools that remove the requisite amount of underwater silt and different compositions and make the excellent constructions accurate that a civil engineer wonders.
• Dredging is also essential to make the marine ecosystem pollution-free. It helps in the eco-friendly disposal of deposited polluting toxicants and harmful materials without causing any harm to the marine ecosystem.
• Dredging helps preserve flora and fauna in water bodies and is also used for recreational activities.

Various Dredging Methods

The dredging process combines digging the soil in the water bed and removing or extracting that soil from the excavated surface by creating a vacuum or plain suction. Technologies assist modern dredges; however, the basic excavation methods of dredges have remained the same since the late 1800s. Depending on how the debris is extracted from the site, there are three main types of dredges.

The common types of dredging methods are-

Mechanical Dredging

Mechanical dredging is the process in which the sediments are picked up using mechanical tools such as buckets and grabs mounted on a large barge and placed in a waiting barge until the solids settle down. Dipper Dredges and clamshell dredges, named after the scooping buckets they use, are the most common types of mechanical dredges that can work in tightly confined areas.

Mechanical dredging is usually carried out near the shoreline. Hence, mechanical dredging is used to remove sediment on land or shorelines.

The dredged sediment is picked up and placed on nearby land or in water or, most of the time, in another barge dedicated to carrying the sediment. If the dredging is done near the shoreline, the sediment can be directly transferred to a truck or railway wagon.

The mechanical dredging operation can be done using a barge or operated from shore.

If the mechanical dredger is onshore, it has a limitation of covering the area as it can only be used near the shoreline. Barge-type mechanical dredgers can be operated in any water; however, it will be most effective near docks, piers, etc.

Mechanical dredging can be a continuous process. However, the quantity of the sediment will be limited to one scoop, which is lifted every time to remove the residue. The mechanical type can dredge hard compacted sediments, and water carryover is way less than hydraulic dredging.

Hydraulic Dredging

In the hydraulic dredging process, centrifugal pumps remove the sediment from the dredged site. Material from the channel bottom is sucked into the pipe.

The sediment is mixed with water and made into a slurry mixture, making it easier for the pump to transfer. Depending on the pumping distance, a booster pump can be fitted inline to transfer the sediment to the nearest shore through larger ships to maintain a constant production rate.

One of the significant advantages of the hydraulic dredging process is the elimination of other transport mediums or equipment, as the sediments can be directly transported to the shore facility, saving additional expenditure and time.

The advantages of hydraulic dredging are:

• Reduces capital costs
• Reduces use of equipment and transportation
• Reduces energy and emissions compared to the mechanical dredging process
• Safe and efficient
• Hydrodynamic Dredging

Hydrodynamic dredging is generally used to maintain the channel, port, harbour depths, etc. If a new site needs to be freshly dredged, this method won’t prove valuable and efficient. Once the area is dredged, it must be constantly maintained to avoid unsafe navigation by retaining the required depths.

Related Read: Mastering Ship’s Navigation

This method utilizes water injection technology, which injects large amounts of water using nozzles attached to a horizontal jet bar powered by pressurized pumps. As the water spray from the nozzle hits the water bed, it fluidizes the sediments, making them loose. This loose sediment near the channel bed flows down to the deeper areas due to natural current.

As the natural flow helps sediment transport, this method is cost-effective and much more environmentally friendly than the other two.

Different types of dredging ships

As per the classification of the dredger, they can be further classified into different types:

Types of Mechanical Dredgers

These are fixed in place using anchor piling, known as spuds.

Bucket Dredger: The bucket dredger is usually a fixed-type stationary dredger that rotates in an arc by winches around the dredging site. The scrapping end is fitted with a bucket, which removes the sediment or bottom material, and when turned upside down, the sediments are unloaded on a barge.

Grab Type Dredger: This is a stationary dredger with a grab as a dredging tool (Two equivalent scoops or shells operated hydraulically). Due to its design, It is also known as a clamshell dredger. There can be different designs of the grab, which can be used for deepwater dressing.

Backhoe Dredger: Also known as fixed arm dredger, it is a stationary type dredger usually mounted on a barge or works near the banks. The dredging equipment is a half-open shell with a fixed-length hydraulic arm used in shallow waters and near harbour sites.

The main types of Hydraulic Dredges include

Suction Dredger: It is a stationary dredger generally used for mining sand. It is also the best equipment for removing sludge from wastewater treatment plants or where heavy-duty sediment removal is required. The suction pipe of this dredger is inserted into the sand deposit, and water jets are used to bring the sand up from the excavation site. The sediment can be pumped by sucking the sediments into the pipeline and transferring it to the reclamation site or loaded into barges, depending upon the location and available transfer arrangement.

Cutterhead Suction Dredger: It is another stationary dredger with a cutter head on the suction end to loosen the base to be dredged. Like the plain-suction dredge, the sediments are sucked and pumped via a discharge pipeline ashore or into barges. The cutter head can be of different designs and materials, depending upon the properties of the surface to be dredged. It aids in removing sediment from hard surfaces.

Auger suction dredge operates on the same principles as a cutter-suction dredge, except that the mechanical cutting tool is a rotating Archimedean screw placed at right angles to the suction pipe.

Trailing Suction Hopper Dredger: This is a self-propelled ship carrying the dredger equipment having a hold or hopper arrangement to fill it with excavated material while following a pre-set dredging operation. This type of dredger can open the bottom of the hold to unload the dredged material into the designated site. This dredger is mainly used in open water such as canals, rivers, estuaries, etc.

Reclamation Dredger: This assists equipment in the dredging operation, not the dredger itself. It is used to empty the hopper barge sediments using a suction pipe, which can be lowered into the hopper barge hold. Additional water can be sprayed to make the sediment slurry for easier suction and transfer to the dedicated site or shore depot.

As explained earlier, hydrodynamic dredgers have only one type: Water Injection dredgers.

Few other types of dredger ships 

Amphibious dredgers: These ships have the unique constructional feature of working out of the water surface using long legs as their base. They can be equipped with grabs, buckets or a shovel installation.

Air-lift dredgers: This dredger uses high-pressure air jets instead of water jets for material flow at the mouth of the suction pipe.

Bed leveller: This type is used to level the bed surface, which has recently been dredged. It consists of a long flat blade or heavy bar connected to a tugboat at the end, and when it is pulled, it will level the surface on the dredged surface over short distances.

A hopper dredge is a ship that sucks up the sediment slurry and holds that slurry in the ship (hopper) until it gets to its destination. A pipeline dredge sucks up the sediment slurry and pumps it through a pipeline directly to its destination.

Related Read: Different Types of Dredgers Used in the Maritime Industry

Effects of Dredging

But like every coin has two sides, even dredging, despite all the positive attributes to the process, has negative points. These negative points are also important because they tend to impact the existence and life of the marine habitat.

These adverse effects of dredging are briefed as follows:

• When dredging is carried out for marine engineering or construction work, a large amount of water must be removed and stored at another location. This creates a minor storage problem but extensively affects the life of flora and fauna prevalent in that water. This is due to a change in the mineral composition of water before and after dredging and depositing it back in its source after construction.
• Dredging impacts the crops badly in the regions where it is carried out to de-silt the rivers, primarily intended to quench the irrigation demand of the area. Along with silt, essential minerals also get dredged out, leaving the resultant water and land lacking in nitrates and phosphates.
• Also, if dredging is carried out to serve the cleaning purpose, removing the toxic waste alarms the safe disposal problem. If it is disposed of on land to make the ground barren and in other less critical water bodies, it harms the living creatures in that water body.

Related Read: Effects of Dredging on the Marine Environment

These ill effects of dredging become insignificant compared to applications and the importance of dredging but should be kept in mind and catered to where necessary.

Conclusion

The dredging industry has developed throughout the world in the last two decades. It serves multi-purposes such as cleaning, maintenance, disposal, transportation, excavation, etc., at a time. It helps make the water navigable and makes fishing easier, even in shallow creeks. It helps remove contaminants from the waterways and recreate damaged areas through reclamation works.

But a vital thing we must cater to while dredging is the safe dumping of managed. It should be disposed of where no significant landform or life-form get harmed. Also, in some areas, dredging alters the mineral composition of the water; precautions should be taken to oversee the alterations caused by the change in mineral composition.

By putting small things in place, we can prevent the occurrence of a significant catastrophe. Today, with the advancement in dredging technology, we have pushed dredging towards higher efficiency with lower environmental impact.

Frequently Asked Questions

1. Why is dredging bad?

Dredging is harmful to marine flora and fauna. It impacts them negatively in many ways through habitat destruction, entrainment, noise pollution, sedimentation, and contamination.

2. Why should you dredge a pond?

Maintaining perfect water quality is essential for a healthy pond. Dredging a pond aids in the proliferation of good bacteria that aid in breaking down the organic waste that collects at the bottom of the pond.

3. There are how many types of dredging methods?

There are three kinds of dredging methods: mechanical dredging, hydraulic dredging and airlift dredging. Dredging is usually performed using equipment called dredges that are held on a barge.

4. How does a dredge work?

Dredges are unique equipment that loosens the bottom sediment and creates a vacuum to suck and pump out the unwanted sediment and debris, which is then transferred to a disposal site.

5. How does dredging affect the water quality?

Dredging impacts the water quality of marine systems manifold. It depends on the nature of the dredged material, as the seabed disturbance changes the chemical composition or the ph of the water body, ultimately impacting the whole marine ecosystem. For instance, excessive sand dredging degrades rivers and estuaries.

Disclaimer: The author’s views expressed in this article do not necessarily reflect the views of Marine Insight. Data and charts, if used in the article, have been sourced from available information and have not been authenticated by any statutory authority. The author and Marine Insight do not claim it to be accurate nor accept any responsibility for the same. The views constitute only the opinions and do not constitute any guidelines or recommendations on any course of action to be followed by the reader.

The article or images cannot be reproduced, copied, shared or used in any form without the permission of the author and Marine Insight. 

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Cargo ships are classified into various types based on purpose, size, type of cargo etc.

The economic factor is of prime importance in designing a merchant ship. Every owner wants maximum return on their investment, which means a ship’s construction not only depends on the current economic necessities, but the factor of future adaptability also plays a part.

From the preliminary design of a vessel due for construction, the following information can be obtained:

1. Dimensions
2. Displacement
3. Stability
4. Propulsive characteristics and hull form
5. Preliminary general arrangement
6. Principal structural details

A layout of the various ship types and their subdivisions will be listed, covering a wide range of all vessels in operation. 

The type of ship plays an important role in deciding the above-mentioned parameters.

Related Read: What are Ship Prefixes for Naval and Merchant Vessels?

Types of Ships

Ships are mainly classified into the following types:

1. Container Ships

2. Bulk Carrier

3. Tanker Ships

4. Passenger Ships

5. Naval Ships

6. Offshore Ships

7. Special Purpose Ships

1. Container Ships

As the name suggests, a vessel structured specifically to hold huge quantities of cargo compacted in different types of containers is referred to as a container vessel (ship).

Types of Container Ships On Basis Of Sizes:

• Panamax
• Suezmax
• Post-Panamax
• Post-Suezmax
• Post-Malaccamax

Learn about different types of container ships. 

Refrigerated Container Ships: These Vessels carry refrigerated cargo (mainly in refrigerated containers)

2. Bulk Carrier Ships

3. Tanker Ships

Tanker ships are specialised vessels for carrying a large amount of liquid cargo. Tankers are further sub-divided into different types based on the cargo they carry.

Read in detail – What are tanker ships?

The main types of tankers are:

Oil Tankers: Oil tankers mainly carry crude oil and its by-products.

Liquefied Gas Carriers: A gas carrier (or gas tanker) is designed to transport LPG, LNG or liquefied chemical gases in bulk.

Chemical and Product Carriers: A chemical tanker is a type of tanker ship designed to transport chemicals and different liquid products in bulk

Other types of tankers: Some other types of tankers are juice tankers, wine tankers, integrated tug barges etc.

Based on their size, tankers are further divided into various types such as:

4. Roll-on Roll-Off Ships

5. Passenger Ships

Passenger ships, as the name suggests, are mainly used for transiting passengers.

They are mainly classified into:

Ferries – Vessels used for transiting passengers (and vehicles) on short-distance routes are called ferries.

Cruise Ships – Mainly used for recreational activities, cruise ships are like luxurious floating hotels with state-of-the-art facilities.

They are further classified as:

• Liners, Cruise Ships, Pilgrimage Ships
• Cross Channel Ferries, Coastal Ferries, Harbour Ferries
• Arctic and Antarctic Cruises

Learn more about different types of passenger ships. 

6. Offshore Vessels

Offshore vessels mainly help in oil exploration and construction jobs at sea. Offshore vessels are of several types.

Some of the main ones are:

• Supply Ship: Vessels that supply to offshore rigs
• Pipe Layers: Vessels engages in laying pipes and cables
• Crane Barges or floating cranes: A crane vessel, crane ship or floating crane is a ship with a crane specialized in lifting heavy loads
• Semi-submersible Drill Rigs: These are Mobile Offshore Drilling Units to make stable platforms for drilling oil and gas
• Drill Ships: A drillship is a merchant vessel designed for use in exploratory offshore drilling of new oil and gas wells or scientific drilling purposes
• Accommodation Barges: Could be a stand-alone floating hotel or can include accommodation as well as space for Cargo
• Production Platforms: To extract and process oil and natural gas or to temporarily store product until it can be brought to shore for refining and marketing
• Floating Storage Unit (FSU) – Floating vessel mainly used for storage of oil and by-products.
• Floating Production and Storage Unit (FPSO): A floating production storage and offloading unit is a floating vessel used by the offshore oil and gas industry for the production and processing of hydrocarbons and the storage of oil
• Anchor handling vessels – These are used for offshore construction and installation operations.
• Diving vessels – Are vessels used by divers for diving in the ocean for underwater jobs.

Learn more about different types of offshore vessels here.

7. Fishing Vessels

Ships or boats used for recreational or commercial fishing at sea are called fishing vessels.

Fishing vessels are mainly classified into two types – trawlers and non-trawling vessels.

• Trawlers, Purse Seiners: A fishing trawler, also known as a dragger, is a commercial fishing vessel designed to operate fishing trawls. Trawling is a method of fishing that involves actively dragging or pulling a trawl through the water behind one or more trawlers. A purse seine is a large wall of netting deployed around an entire area or school of fish. The seine has floats along the top line with a lead line threaded through rings along the bottom. Once a school of fish is located, a skiff encircles the school with the net.
• Factory Ships: A factory ship, also known as a fish processing vessel, is a large ocean-going vessel with extensive on-board facilities for processing and freezing caught fish or whales

Learn more about types of fishing vessels here.

8. Speciality Vessels

Speciality vessels are constructed and used for specific purposes.

Tugs: A tug (tugboat) is a boat or ship that manoeuvres vessels by pushing or towing them.

Tenders – A boat or a larger ship used to service or support other boats or ships, generally to transport people and/or supplies, is called a tender vessel.

Pilot Crafts – Pilot crafts are used for the transportation of harbour pilots.

Cable Layers – Cable laying vessels help in laying cables onto the sea bed. 

Research Vessels – They are special types of vessels used to carry out a variety of research at sea. Some of the most common types of research vessels are – seismic vessels, hydrographic vessels, oceanographic vessels, polar vessels etc.

Related Read: 12 Noteworthy Research Vessels

Salvage Vessels – Salvage vessels are vessels engaged in salvage operation; recovery of lost property at sea.

Lightships: A light vessel, or lightship, is a ship that acts as a lighthouse. They are used in waters that are too deep or otherwise unsuitable for lighthouse construction.

Barge Carriers: A barge is a flat-bottomed boat built mainly for river and canal transport of heavy goods.

Timber Carriers: Vessels that carry timber

Livestock Carriers: Vessels that carry livestock/animals

Ice breaker ships: They are used for cutting ice deposits in extremely cold climate conditions to make waters navigational.

Related Read: What is an Ice Breaker Ship?

9. High-Speed Craft

High-speed crafts are a special type of technologically advanced high-performance (typically high speed) marine vehicles. Though most of these technologies are not used in commercial vessels, a few have been successfully implemented and tested in conventional merchant vessels of small scale.

Some of the main types of high-speed crafts are:

• Multihulls including wave piercers
• Small waterplane area, twin-hull (SWATH)
• Surface effect ship (SES) and Hovercraft
• Hydrofoil
• Wing in Ground Craft (WIG)

Learn more about different types of high-speed crafts.

10. Dredgers 

Dredging is an excavation activity usually carried out underwater, in shallow seas or freshwater areas, to gather up bottom sediments and widen.

Dredgers are vessels with excavation tools used for removing sand and other types of deposits from the seabed. Dredgers are used for several purposes, such as making shallow coastal areas navigational, deep-sea mining etc.

Dredgers are mainly classified into two types:

1. Mechanical dredgers
2. Hydraulic dredgers

Learn in detail about different types of dredgers. 

You might also like to read:

• A Guide to Different Types of Boats
• Different Types of Barges; Uses And Differences
• A Guide To Types of Fishing Vessels
• Types of Sailboats – A Comprehensive Classification
• Types Of Mobile Offshore Drilling Units (MODU)

Disclaimer: The authors’ views expressed in this article do not necessarily reflect the views of Marine Insight. Data and charts, if used in the article, have been sourced from available information and have not been authenticated by any statutory authority. The author and Marine Insight do not claim it to be accurate nor accept any responsibility. The views constitute only the opinions and do not constitute any guidelines or recommendations on any course of action to be followed by the reader.

The article or images cannot be reproduced, copied, shared or used in any form without the permission of the author and Marine Insight. 

A Guide To Types of Ships appeared first on Marine Insight - The Maritime Industry Guide

One of the major artificial waterways in the world, Panama Canal connects the Atlantic Ocean and the Pacific Ocean, cutting across the Isthmus of Panama- a narrow strip that separates the Caribbean Sea from the Pacific Ocean.

Completed construction in August 1914, the 77 km-long Panama Canal helps ships sailing between the east and west coasts of the US to shorten their journey by 15,000 km. Similarly, the canal saves up to 3,700 km for vessels transiting between Europe and East Asia.

Currently, the Panama Canal plays a significant role in the US economy since it handles a substantial share of US shipping. In the fiscal year 2017, the canal witnessed the passage of a total of 13,548 vessels, carrying 403.8 million Panama Canal tons of cargo.

Do you know about these interesting facts about the Panama Canal?

Geographically, the oceans that Panama Canal connects with are not at the same level; the Pacific Ocean lies a little higher than the Atlantic Ocean.

This difference in the sea level requires ships to get up over the terrain of Panama- up to 26 meters above sea level- in order to reach the other end of the canal.

With the help of Lock Gates, the vessels entering the canal are lifted to a higher level and later dropped down to the sea level at the other end of the canal.

The Panama Water Lock System is considered to be one of the greatest engineering services undertaken at that time, purporting to the needs of the ships to save transit time.

Design of the Panama Canal Locks

The Panama Water Lock System consists of a total of three sets of locks-12 locks- to help vessels transit between the Atlantic and the Pacific Oceans via artificial lakes and channels.

Before the canal expansion, which was completed in 2016, the canal had two lines with two sets of the lock at both ends of the canal.

The expansion of the canal resulted in a third lane and a third set of locks that allow the entry of larger vessels.

The locks, located on the Atlantic and the Pacific sides, lift and lower the vessels to/ from the Panama Canal that is situated 26 metres from sea level.

On the Pacific side, the lock system features the two-chambered Miraflores Locks and the one-chambered Pedro Miguel Locks, while the three-chambered Gatun Locks sit on the Atlantic Side of the Panama Canal.

Since these three sets of locks are paired, two parallel flights of locks are located at each of the three lock sites, allowing the simultaneous movement of vessels in opposite directions.

However, in practice, only six massive pairs of locks are used by ships for transit now, and the ships move in one direction at a time due to safety constraints to cross the Culebra Cut.

It also means that the ships currently use both lanes of the lock only to move in one direction at a time.

The original locks of the Panama Canal are 33.53 meters (110 feet) wide, while each lock features a length of 320 meters (1,050 feet). The walls of each lock have a thickness ranges from 15 meters (at the base) to 3 meters (at the top).

The dimensions of the lock decide the size of a ship, which is also known as Panamax- that can pass through the canal. The third set of locks opened after the expansion project allows bigger vessels to cross the canal.

The new Panamax metrics, with the new locks, allows the ships with an overall length of 366 meters, a beam of 49 meters and a draft of 15.2 meters.  The total lift, the capacity to raise or lower a vessel, of the locks are; Gatun locks-85 feet, Pedro Miguel locks-54 feet and Miraflores- between 64.5 feet and 43 feet due to the extreme tides.

The gates of the Panama Canal locks separate the champers, and are strong enough to hold thousands of litres of water. The water locks are filled or emptied in less than 10 minutes and each pair of lock gates takes two minutes to open.

The size of the Panama lock gates ranges from 14.33 to 24.99 meters and measures 2.13 meters in thickness. Each gate features two leaves that measure 19.81 meters in width and these leaves are close to a “V” shape with the point upstream, allowing the gates to handle the force of the water.

The gates are only opened when the water level is equal on both sides. A fender chain, weighing around 30,000 pounds, at the end of each lock prevents ships from ramming the gates before they open.

In order to let the vessels pass the lock, each chamber needs to be filled with 26,700,000 US gallons of water. The locks are operated using the gravity flow of water from lakes such as Gatún, Alajuela, and Miraflores.

The lock system includes 18 feet wide water culverts attached to it, performing the duty of carrying water from these lakes to the chambers to raise the vessels and from chambers to the next lock or the sea to lower the vessels.

Operated electrically, the entire process of the lock system is controlled from a control room located on the centre wall of the upper flight of locks.

The control rooms guide the vessels through the lock chambers using electric towing locomotives. Ships are pulled with the help of these machines, called “mules”, using a cable through the locks.

On average, ships require six of such mules, three on each side, when using the locks to enter or exit the canal.

Operation of the Panama Canal Locks

The whole operation of the Panama Water Lock System works can be described in a few steps:

1. The vessel approaches towards the lower chamber of the canal locks;

2. the valve of the first chamber opens and water flows by force of gravity from the higher chamber to the lowest one, bringing the water level to the sea level;

3. the locked gate opens to allow the ship into the chamber, and the gate closes behind it;

4. the valve of the next chamber is opened to increase the water level to that of the first chamber;

5. the gate of the lock is opened and the ship enters the next chamber;

6. The water level is equalized again and the ship finally exits the lock and enters the 77 km long canal.

At the other end of the canal, a similar process will be performed in order to lower the vessel to sea level.

In detail:

For a ship entering the canal from the Atlantic end, travelling in a southeast direction, the first entry will be into the first (sea level) lock chamber located at the Gatun Locks.

After the vessels entered the chamber, the watertight lock doors are closed by the lock-master and the valve is opened to allow the flow of water from the adjacent second lock chamber, 28 feet above sea level.

Water flows through underground pipes into the first chamber until the water levels are equal.

However, no pumps are used here; the entire operation of equalizing the water levels between the locking chambers on the Panama Canal depends on the principles of gravity to move the water and on the fact that water seeks its own level.

When the water levels of two adjacent chambers are equal, the water stops flowing from the water culverts.

Once the water levels between the first and second chamber are the same, the valve gets closed by the lock-master and the watertight lock doors between the first lock chamber and the second lock chamber are opened subsequently.

This process allows the ship to proceed to the second lock chamber. The first operation is repeated then between the second lock chamber and the third lock chamber, which raises the ship to the level of Gatun Lake.

After the closure of the final valve and opening of the watertight lock door, the ship is raised 85 feet above sea level and is able to continue its journey to the Pacific.

The same process inversely is followed in order to send the ship back to sea level. At the Pedro Miguel Locks on the Pacific end of the canal, when the ship enters the first chamber, the watertight doors are closed and the valve gets opened on that lock chamber, allowing water to drain from the first lock chamber into the relatively lower second lock chamber.

After the water level between the two chambers is at the same level, the watertight doors are opened allowing the ship to continue to transmit down the Gaillard Cut to the Miraflores Locks, where the operation of lowering the ship to sea level is completed.

You may also like to read – 4th Engineer’s First Journey Through The Panama Canal 

Disclaimer: The authors’ views expressed in this article do not necessarily reflect the views of Marine Insight. Data and charts, if used, in the article have been sourced from available information and have not been authenticated by any statutory authority. The author and Marine Insight do not claim it to be accurate nor accept any responsibility for the same. The views constitute only the opinions and do not constitute any guidelines or recommendation on any course of action to be followed by the reader.

The article or images cannot be reproduced, copied, shared or used in any form without the permission of the author and Marine Insight. 

How the Water Locks of Panama Canal Work? appeared first on Marine Insight - The Maritime Industry Guide

“Have you ever crossed the Panama Canal?” One of many questions we mariners encounter while interacting with landlubbers is if they are smart enough not to ask questions like “Where do you sleep at night on ship?”.

The Panama Canal is perhaps one of the most remarkable feats of engineering ever conceived by humanity. Its sheer size tells a beautiful tale about human endurance, determination, and accomplishment.

Related Reading: 10 Famous Shipping Canals In The World

As a seafarer, I would say we are a privileged lot who get to see the best artificial waterway in a very intimate way by sailing through it. Thus it would not be wrong to mention that it is a moral obligation for us mariners to know a few intricate facts about this wonder of the modern world, as labeled by the American Society of Civil Engineers.

Let’s take a look at ten crucial Panama Canal facts below:

Who Built The Panama Canal?

Everyone knows that the United States of America built the Panama Canal under President Theodore Roosevelt, but very few know that the French started the work. It was Mr. Ferdinand de Lesseps, a French diplomat, who began the work in 1881. The work had to be stopped in 1894 because yellow fever and malaria claimed the lives of an estimated 22,000 workers, and spending nearly USD 287 million bankrupted Mr. Ferdinand de Lesseps.

Americans undertook the leftover work in 1904 after helping Panama cede from erstwhile ‘Greater Colombia.’ Constructing a dam to provide water for the canal was a challenge. However, under the able leadership of Mr. John Frank Stevens and later Major George Washington Goethals as chief engineer, the Madden Dam was built, and the canal was completed in 10 years. It was on 15 August 1914, two years before the target year of 1916, when the Panama Canal was officially inaugurated.

Related Read: A Brief History of the Panama Canal

Which was the first vessel to cross the Panama Canal? 

As per records, the first ship to cross the Panama Canal was SS Ancon. She was an American flag cargo and passenger ship owned by the Boston Steam Ship Company. She was about 150 meters in length, 18 meters in beam, about 9600 Gross Registered Tonnage, and drew a draft of about 8.8 meters. She played a vital role in building the canal by ferrying workers, construction materials, and, notably massive amounts of cement from New York to Panama for constructing the Panama Canal.

How much time is saved by crossing It? 

Panama Canal was first envisioned by Charles V, Holy Roman Emperor and king of Spain, in the year 1534. He was convinced that a canal across the isthmus of Panama would significantly reduce the distance between Spain and Peru, thus giving them a military advantage over the Portuguese. Though it took nearly four centuries for his dream to materialize, since its inauguration, Panama Canal has reduced the sailing distance from the Atlantic to the Pacific and vice versa by a vast 8000 nautical miles (approximately). If we sail with an average speed of about say 15 knots, then it will be 22 long days!

On the contrary, crossing the Panama Canal takes around 8 to 10 hours. Panama Canal not only saves money and time for owners and ship operators but, in fact, also prevents enormous amounts of CO₂ emissions, helping the shipping industry to reduce its carbon footprint.

Panama Canal Facts Infographic:

How much does it cost to transit the Panama Canal?

Panama Canal authorities calculate tolls using a Panama Canal Universal Measurement System (PC/UMS), based on the international standard of vessel measurement established by the International Convention of Measurement of Ships in 1969.

A mathematical formula is applied to calculate the total ship’s volume to determine net Canal Tonnage. A net Canal tonnage is 100 cubic feet of volumetric capacity. Then, depending on whether the vessel is laden or in ballast, the appropriate rate is applied. Warships and other Naval Auxiliary vessels are charged based on their displacement tonnage. One displacement ton is equivalent to one long ton or 35 cubic feet of salt water.

For practical purposes, a typical IMO type III chemical tanker of around 50,000 DWT pays around USD 135,000 in toll. In contrast, an LNG tanker of neo-Panamax size 83,000 DWT pays around USD 260,000 in toll. The smallest toll was paid by Mr. Richard Halliburton in the year 1928 of USD 0.36 for swimming across the canal.

Related Read: Different Types of Tankers: Extensive Classification of Tanker Ships

How do the locks work, and why are they there in the first place? 

There is a total of twelve locks in the Panama Canal system. The first set of locks from the Pacific entrance to the canal is known as Miraflores locks. It is a two-step flight that lifts or lowers ships 54 feet above the mean sea level. Then comes Pedro Miguel’s locks.

It is a single-step flight that lifts or lowers ships 31 feet above mean sea level. Pedro Miguel locks then lead to Gatun Lake via Culebra cut. The final lock is known as the Gatun Lock. It is a three-step flight that lifts or lowers ships 85 feet above the mean sea level and opens to the Atlantic Ocean. All three sets of locks are in a pair to ensure that, at least in principle, ships pass in opposite directions.

The main purpose of these locks is to ensure that Gatun Lake does not flow outwards to the Atlantic or the Pacific Ocean. This provides sufficient draft is available at all times for ships to pass.

Locks work on the basic principle of gravity and floatation. The height difference between Gatun lake and the Pacific & Atlantic Oceans causes water to flood and empty the locks through culverts. Huge valves control the flow of water. A control centre manages the entire system at respective lock gates. When lock gates flood, the ship floating inside the lock gate rises with the rising water level and then enters the consecutive lock gate for further rise. The same technique is used to lower the ship by emptying the lock gates.

Related Read: How do the Water Locks of Panama Canal Work?

What is the maximum draft allowed to transit the Panama Canal? 

Every year ACP (Autoridad del Canal de Panamá) or Panama Canal Authority issues a notice giving details of size and draft limitation for vessels intending to transit the Panama Canal. With the opening of new locks for commercial traffic on 26 June 2016, there are different requirements for ships travelling with old and new locks. Old locks are called Panamax locks, whereas new ones are referred to as neo-Panamax locks.

As of the year, 2018 maximum draft for Panamax locks is 12.04 meters (39 feet 6 inches) of Tropical Fresh Water (TFW). Tropical Fresh Water (TFW) is 0.9954 gms/cc at 29.4°C (85°F). The maximum draft for neo-Panamax locks is 15.2 meters (49.87 feet) of Tropical Fresh Water (TFW).

What are the required pre-arrival preparations?

It is a known fact that the Panama Canal is one of the essential waterways in the world. To ensure the continued safe transit of vessels, there are stringent regulations that control the entire transit system of the Panama Canal. Canal transit should be booked via the agent, who would also send the list of pre-arrival documents. These documents are required for vessel clearance upon arrival.

Vessels arriving at the Atlantic or Pacific anchorages must contact the Port Entry Coordinator (PEC) in Cristobal or Flamenco signal stations on VHF Channel 12 before the evolution occurs. Upon arrival at Atlantic or Pacific anchorages, Panama Canal Authority (ACP) inspectors board the vessel to carry out a pre-transit inspection. All bridge equipment, steering gear, mooring winches, associated equipment, main engine, and other auxiliary machines must work correctly to avoid delays or rejection during ACP inspection.

Panama Canal is in ECA (Emission Control Area); thus, before transit, change over from HFO (Heavy Fuel Oil) to LSMGO (Low sulfur marine gas oil) may be required depending on ship type. The ship’s crew should also be familiar with PCSOPEP (Panama Canal Ship Board Oil Pollution Emergency Plan). PCSOPEP notification and oil spill drill per PCSOPEP should also be carried out before arrival.

Related Read: 10 Points to Remember When Transiting a Narrow Channel

Navigation Challenges  

Navigating the Panama Canal can be challenging. Though Panama Canal pilots are known for their thorough professionalism and skilled navigation, responsibility for safe navigation lies with the ship’s master and crew.

Special care should be taken, especially when a vessel is in the lock and the locked gate is open. The sudden gush of water creates an effect that local pilots call ‘The Hydraulic Effect,’ this pushes the vessel astern, and full main engine power is required to maintain the position. During this, the forward and aft station duty officer should constantly communicate with the bridge and inform the condition of lines passed by mules.

The other section where special care should be exercised is the ‘Culebra Cut,’ also formally known as the ‘Gaillard Cut.’ This narrow stretch of the Panama Canal cuts through the continental divide in Panama. Sharp-cut and narrow passages make it tricky and challenging.

Honorary Pilots

Interestingly, the Panama Canal Authority (ACP) appoints a few honorary pilots, generally masters, who have completed 100 transits through the Panama Canal. Most recently, Capt. Sonjoy Sen of WWL (Wallenius Wilhelmsen group) received an honorary Panama Canal Pilot’s Licence in 2015.

Commodore Ronald Warwick, master with Cunard Liners who commanded RMS Queen Marry II, was awarded honorary pilot of Panama Canal by Panama Canal Authority (ACP) for crossing Panama Canal more than 50 times.

Competitors of the Panama Canal

Although the Panama Canal is the only canal between the Pacific and the Atlantic Ocean, there is also a proposal for another canal to cut across Nicaragua. It is to be known as the Nicaragua Canal.

In 2006, President of Nicaragua Enrique Balaños announced his intention to build this canal. In 2012, the Nicaraguan government, together with Hong Kong Nicaragua Canal Development Investment Company (HKND Group), signed a memorandum of understanding in which HKND Group would finance the entire project and, after completion of the project, would operate it.

However, the Hong Kong Nicaragua Canal Development Investment Company (HKND Group) became bankrupt after the 2015-16 Chinese stock market turbulence. This and local and environmental activists’ protests brought this project to its knees. Despite this, the present Nicaraguan government is committed to constructing this canal. If this project becomes a reality, it may give Panama Canal serious competition.

Reading about the Panama Canal facts gives one a glimpse of this magnificent piece of an engineering marvel. Its true beauty can only be captured and felt by actually sailing through it. We hope all fellow seafarers will sail through it at least once in their lifetime and experience Panama Canal in all its glory.

Do you know any other Panama Canal Fact that can be added to this list?

Let’s know in the comments below.

Frequently Asked Questions About the Panama Canal

1. What is so unique about the Panama Canal?

The Panama Canal joined the Atlantic and Pacific Oceans when it opened in 1914. Hence, it shortened the journey for ships that had to sail through the southern tip of South America.

2. How much distance does Panama Canal Save?

It saves up to 8000 nautical miles, depending on where the ship is sailing from.

3. Why is the Panama Canal so famous?

The canal is popular as it saves time and money and reduces carbon emissions of the shipping industry. It helps shippers to transport grains and other products conveniently and swiftly.

4. Does the Panama Canal make money?

Panama Canal generates enormous revenue from its toll fee. The toll revenue was three billion US Dollars in 2021.

5. Who built the Panama Canal?

Initially, it was the French; however, Theodore Roosevelt negotiated the Hay-Bunau Varilla Treaty, which gave the US control of the canal zone. The US began work in 1904 and completed it in a decade by 1914.

6. How many ships pass through the Panama Canal every day?

Around 40 ships pass through the canal each day.

You may also like to read – the 4th Engineer’s First Journey Through The Panama Canal. 

Disclaimer: The author’s views expressed in this article do not necessarily reflect the views of Marine Insight. Data and charts, if used in the article, have been sourced from available information and have not been authenticated by any statutory authority. The author and Marine Insight do not claim it to be accurate nor accept any responsibility for the same. The views constitute only the opinions and do not constitute any guidelines or recommendations on any course of action to be followed by the reader.

The article or images cannot be reproduced, copied, shared, or used in any form without the permission of the author and Marine Insight.

10 Important Panama Canal Facts Everyone Should Know appeared first on Marine Insight - The Maritime Industry Guide

What is Wall Wash Test (WWT)? All non-chemical tanker folks must be wondering. You may have encountered this term at least once during your exam or sea time, but you’re still unsure about it. Don’t worry; even if you’re a beginner or looking to join a chemical tanker for the first time, we’ve got you covered in this article.

The Wall Wash Test (WWT) is performed on chemical tankers after completing the tank cleaning operation of cargo tanks.

Wall Wash Test (WWT) is required to determine the vessel’s cleanliness, which means whether the vessel is ready or not to load the next cargo and if further cleaning is required or not.

The Wall Wash Test (WWT) requires ship staff to enter the cargo tanks and collect samples from various locations. 

An instrument called a spectrometer (UV Test apparatus) is generally provided on board by the vessel charterers or owners to perform the Wall Wash Test (WWT).

A spectrometer provides result data and UV scan graphs of Hydrocarbon (HC), Chloride (Cl), Permanganate Time Test (PTT), APHA colours, etc., which play a deciding role in determining whether the tanks are suitable for loading the next cargo or not.

Ship staff must familiarise themselves with the use of spectrometers on board to perform the Wall Wash Test (WWT) on board and to ensure compliance with the required cleanliness standards. The charterers may request the result data and UV scan graphs of the Wall Wash Test (WWT) at any time.

Once the vessel reaches the loading port, a cargo surveyor comes on board to take the wall-wash samples. Samples taken by the surveyor will be inspected at a shore-based laboratory. The cargo loading will commence only after the samples taken by the surveyor are passed.

Now for a better understanding of the Wall Wash Test (WWT), we will discuss the following:

1. Cargo Tank Cleanliness Standards for Chemical Tankers Tank Cleaning
2. Items/Equipment required for Wall Wash Test (WWT)
3. Procedures and Types of Wall Wash Test (WWT)
4. Wall Wash Test (WWT) vs Wash Water Analysis

1. Cargo Tank Cleanliness Standards for Chemical Tankers Tank Cleaning

The Cargo Tank Cleanliness Standards for Chemical Tankers are defined in the INTERTANKO publication. These standards were developed to simplify the tank cleanliness verification process and reduce the need for in-tank inspections. 

The primary purpose of these cleanliness standards is to provide predictability in terms of cost and time required for tank cleaning. Additionally, they aim to avoid tanks over-cleaning, improve port turnaround, clarify charter-party terms, and reduce the number of in-tank inspections in ports.

Cargo tank cleanliness standards are divided into four standards:

• Visually Clean Standard
• Water White Standard 
• High-Purity Standard
• Ultra-High Purity Standard

Visually Clean Standard

In the Visually Clean Standard, tanks are inspected from the deck level, and no Wall Wash Test (WWT) is required. Tanks must be clean, dry, and visually free of previous cargo residues and foreign matter. There should be no uncharacteristic odour.

Water White Standard

In Water White Standard, tanks are inspected internally, and Wall Wall Wash Test (WWT) is carried out. Tanks must be odour-free, clean, dry, and visually free of previous cargo residues and foreign matter. In Water White Standard Wall Wash colour test is carried out with methanol, acetone, and other suitable solvents. The acceptable result of this colour test is 15 or less.

High-Purity Standard

High-Purity Standard is commonly used for the carriage of Methanol cargo. This standard is often called the Methanol Standard. In High-Purity Standard, tanks are also inspected internally, and the Wall Wash Test(WWT) is carried out with methanol, acetone, and other suitable solvents. This standard also requires tanks to be clean, dry,odour-free, and visually free of previous cargo residues and foreign matter. The acceptable result values are mentioned below:

• Must pass water miscibility/hydrocarbon test 
• Colour < 10 (APHA or ASTM D 1209)
• Permanganate time test(PTT) > 50 mins
• Chlorides must be less than 2 ppm
• UV spectrum passes
• Wash water is to be tested to confirm no more than 100PPM of the last cargo

Ultra-High Purity

The Ultra-High Purity standard requires a more stringent level of cleanliness than the High-Purity Standard. It is used for the carriage of extremely high-spec cargoes.

In Ultra-High Purity Standard, tanks are also inspected internally, and the Wall Wash Test(WWT) is carried out with methanol, acetone, and other suitable solvents. This standard also requires tanks to be clean, dry,odour-free, and visually free of previous cargo residues and foreign matter. The acceptable result values are mentioned below:

• Must pass water miscibility/hydrocarbon test 
• Colour < 10 (APHA or ASTM D 1209)
• Permanganate time test(PTT) > 50 mins
• Chlorides must be less than 2 ppm
• NVM(Non-volatile matter) < 10 ppm
• The last cargo by gas chromatography or other suitable methods < 2PPM
• UV spectrum passes
• Wash water is to be tested to confirm no more than 100PPM of the last cargo

Note: Non-volatile matter and Gas chromatography tests cannot be performed on board. For more details about Cargo Tank Cleanliness Standards for Chemical Tankers, please refer to the INTERTANKO publication.

Items/Equipment required for Wall Wash Test (WWT)

• Spectrometer
• Methanol, acetone, and other suitable solvents laboratory grade
• De-ionised water(D.I. Water) laboratory grade
• Potassium Permanganate Powder(0.1g) for PTT (Permanganate Time Test)
• Hydrochloric Acid solution 
• Sulphuric Acid – Lab Grade
• Nitric acid 
• Silver nitrate 
• Acidified silver nitrate solution (Optional) 
• Chloride standard solution 10 PPM/ 500ML
• Disposable Latex gloves
• Graduated measuring glass cylinders with a metric scale calibrated to contain 50 &100 ml, with stopper and base – Nessler tubes
• Tube rack for Nessler tubes
• Cut Plastic & Metal funnels for WWT
• Sample bottles.(clear & dark 500ml)
• Nessler tubes 50 ml 
• PH Paper
• Penlight 
• Squeeze  bottles with gooseneck
• Pipettes 
• Filter paper
• Shoes cover 
• Tissue Paper
• Sponge
• Thermometer
• Ice cool box (for holding PTT Samples)
• Cell glass for Spectrometer
• UV Cell Glass

Procedures and Types of Wall Wash Test (WWT)

Wall Wash Do’s and Don’ts

• Use a  bucket or a backpack to carry the spray/squeeze bottles containing wall wash solvent, funnel, and labelled sampled bottles for each tank.
• Wear disposable latex gloves, shoe covers, and a clean or disposable boiler suit, along with personal protective equipment (PPE).
• Before taking wall wash samples, make sure to rinse all items in the bucket with methanol after entering each tank. This ensures cleanliness and avoids cross-contamination. Randomly select one spot on each bulkhead for the wall wash sample. With the funnel and sample bottle in one hand, direct the spray/squeeze bottle at least three feet above the funnel and collect the wall wash sample in the sample bottle. Collect approximately 50ml of wall wash from each bulkhead to have enough for testing purposes.
•  Follow company-enclosed space entry procedures when entering the tanks.
•  Don’t take samples from wet bulkheads.
•  Always make a fresh standard solution for testing and clean all sampling tubes and pipettes before use.
• Avoid contamination of samples by human sweat, and always handle the samples with proper care, ensuring full cleanliness.

Types of Wall Wash Test (WWT)

Hydrocarbon (HC)/Water Miscibility Test 

1. For making a standard or reference solution: Add 10ml of the laboratory grade methanol and 90ml of Deionised water(D.I. Water) laboratory grade in a sample/nessler tube.

To make a test solution: Add 10 ml of the tank sample and 90 ml of Deionised water (D.I. Water) laboratory grade in a sample/nessler tube.

Note: Adding more methanol to DI water makes the hydrocarbon test progressively stricter. The dilution ratio depends on the company and load ports. Other commonly used ratios include (25:75, 33:67, and 50:50)

1. Shake or Invert the nessler tube once or twice to mix the D.I. water and methanol.
2. Now leave the sample/nessler tube and wait for 20 minutes.
3. Place the tube on a black surface and switch off the lights. Use a penlight to shine through the side of the tubes while looking down through the liquid column.
4. If a bluish tint is observed, it indicates slight hydrocarbons are present. If a whitish haze is observed, this usually indicates moderate to heavy hydrocarbons are present.
5. If the sample is clear, this means no hydrocarbons are present.
6. To check for specific hydrocarbons and chemicals, you can expose both the reference sample and the test sample to the UV light source in the spectrometer.
7. A reading of 0 in the spectrometer indicates that the test has passed and no hydrocarbons are present.
8. Factors that could affect this test are:

•  Hazy test samples
•  Dirty Column
•  Damp bulkhead
•  Sweat

Chloride (Cl) Test

1. Using the same sample/nessler tube in which the hydrocarbon (HC)/water miscibility tests were conducted (if no hydrocarbons were found), add 5 drops of a 10% silver nitrate solution, and then add 5 drops of a nitric acid solution or use 5 drops of acidified silver nitrate solution
2. Stopper the tube and invert it to mix the contents and wait for 15 minutes.
3. Observe if any turbidity is formed by comparing the sample with the standard. Look down through the liquid against a black background to assess the turbidity.
4. The comparison of wall wash samples to a standard should be performed in a darkened room by looking down through the tubes using a wide-beam penlight held about one foot from the sides of the tubes.
5. For preparing a standard solution for the chloride solution:

  6. Now we have both the standard solution and the wall wash sample ready to run into the spectrometer.

Note: Chlorides must be less than 2 ppm.

Permanganate time test(PTT)

1. Thoroughly clean the sample/Nessler tubes with hydrochloric acid and rinse them three times with tap water. After that, rinse the tubes twice with deionised water and twice with methanol.
2. Label the test tubes and add 50 ml of wall wash to each tube.
3. Mix the permanganate solution by combining 0.1 grams of potassium permanganate with 500 ml of Deionised water(D.I. Water). Prepare a fresh solution every 3 days.
4. Before adding the permanganate solution, fill the tubes to the 50 ml level with a wall wash.
5. Place the tubes in a water bath maintained at 15°C±1°C if methanol is used, 25°C±1°C if acetone is used for ten minutes.
6. Add 2 ml of the permanganate solution to each tube, stopper the tubes, and invert them once to mix.
7. Prepare a standard solution using 50 ml of lab methanol and 2 ml of the permanganate solution to run simultaneously with the other tubes.
8. Place the tubes in the water bath in a dark place and maintain the temperature.
9. Observe the colour at 10-minute intervals and make a note of the times when the colour changes from deep purple to pink and when it fades to a pale, watery yellow and brown.
10. If the standard fades at a shorter time than the test sample, it indicates a problem with the lab, methanol, permanganate solution, or testing containers.
11. Now run the test in a spectrometer. For samples with a reading above 32.0%, they will show a pink colour and pass the test. For samples with a reading below 32.0%, they will appear brown in colour and fail the test.

Note: Permanganate time test(PTT) must be > 50 min.s

In addition to the aforementioned wall wash tests, other important tests are also carried out, such as

Visual Test: This test involves visually inspecting the sample under suitable lighting conditions to detect the presence of any suspended particles or visible impurities.

Odour Test: The odour test is performed to identify any persistent foreign odour that might contaminate the cargo. Filter papers are dipped into both the sample and the standard solution, and immediate smell detection is performed. It is crucial to avoid directly smelling from the tube, particularly if the previous cargo contained toxic substances.

Non-volatile Matter (NVM) Test: The NVM test aims to determine the presence of non-volatile impurities on the tank surface. A specific quantity of the wall wash liquid is evaporated, and the resulting residue (Non-volatile Matter) is weighed. The weight of the residue is then divided by the original sample weight to calculate the non-volatile matter content.

A test method is also available for determining the acid wash colour of various industrial aromatic hydrocarbons, including benzene, toluene, xylenes, refined solvent naphthas, and similar substances. This test provides a standardised procedure for assessing the acid wash colour of these hydrocarbons.

Wall Wash Test (WWT) vs Wash Water Analysis

We are almost at the end, and we hope you have understood the concept of the wall wash test.

Now, you might be wondering what exactly is wash water analysis?

Well, in tankers, seafarers have to make multiple entries into enclosed spaces to comply with wall wash criteria before reaching the loading port. However, due to the past fatalities associated with enclosed spaces, the industry is shifting from wall wash to wash water analysis. 

Wash water analysis involves analysing the wash water that is pumped out of the tank using a spectrometer to determine if the tank is clean enough for the next cargo.

With wash water analysis, it is possible to monitor the tank cleaning process in real time during the actual cleaning operation.

This approach helps to reduce the actual washing of tanks based on a fixed time or physical inspection, as the cleanliness can be accessed through the measurement of the wash water itself.

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• Differences And Correlation Between Spot Rates And Contract Rates in Shipping
• What are Trans-Shipment And Trans-Shipment Ports?
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Disclaimer: The authors’ views expressed in this article do not necessarily reflect the views of Marine Insight. Data and charts, if used in the article, have been sourced from available information and have not been authenticated by any statutory authority. The author and Marine Insight do not claim it to be accurate nor accept any responsibility for the same. The views constitute only the opinions and do not constitute any guidelines or recommendations on any course of action to be followed by the reader.

The article or images cannot be reproduced, copied, shared or used in any form without the permission of the author and Marine Insight.

A Comprehensive Guide To Wall Wash Test (WWT) On Chemical Tankers appeared first on Marine Insight - The Maritime Industry Guide

It is not wrong to say that steel is one of the primary foundations of the global economy. This widely popular iron alloy is one of the widely produced, fabricated, transported, and consumed materials in the current-day supply chain. 

Steel is utilised in diverse forms for countless purposes ranging from industrial to agricultural, domestic to urban, and infrastructural to product-based.

According to reports, global steel production has increased more than ten times over the last 70 years and is slated to reach astronomical levels in future.

This results from a population boom, globalisation, burgeoning infrastructural developments, escalated production, diversified supply chain, and of course, ever-increasing demands from all sectors. Steel and various steel products are crucial elements in global trade and play a pivotal role in the economic growth of any nation.

Transportation of Raw Steel

After extraction of hot steel from blast furnaces in steel furnaces, the steel is cold-hardened and processed further to improve strength, quality and other surface and internal material properties. 

After that, it is shaped or moulded into slabs, ingots, sheets, billets, etc., for further utilisation. This process is also known as the casting of steel. 

Processed bulk steel in these forms is then carried to a steel mill or other production facility. It is then made into commercial standard plates, bars, rods, beams, profiles, channels, pipes etc. 

After the early stages of steel production, there are two kinds of rolling processes in a steel rolling mill. The hardened steel in the raw or semi-processed form is then cast into different forms: 

• Hot Rolling
• Cold Rolling

In hot rolling, the steel is heated to very high temperatures (till red hot) and rolled. In cold rolling, the steel is cooled off rapidly and is treated at low temperatures to improve surface and mechanical properties.

After cold rolling, steel is ready for utilisation from a material point of view. After partial processing of bulk steel after hot rolling or complete processing of steel after cold rolling, the steel is often wound up and rolled up into large coils for convenient transport and storage.

 A coil of steel composed of a hot-rolled or semi-processed steel coil is known as a hot-rolled coil, and this needs to be further treated and cold-rolled for usage. Hot-rolled steel coils are often rolled after annealing. Similarly, a coil of steel made up of cold-hardened and rolled or fully processed steel is known as a cold-rolled coil.

 Once again, they have superior surface and mechanical properties ready to be used in the market after suitable shaping into various items as desired. These steel coils can be unwound again and either be further processed or cold-rolled (for hot-rolled coils) or fabricated into different products or items (for cold-rolled steel coils). 

Most of this steel is carried in cargo vessels as steel coils for convenience. The transport of this steel makes up a considerable portion of the freight market in the commercial supply chain.

 We are also familiar with these vast cylindrical coils being handled at cargo terminals and transported through land routes on trucks and trailers. 

But specific regulations and guidelines are abiding by which the proper stowage and transport of these coils in large quantities are carried out in ships. 

Loading Steel Coils On Ships

These steel coils are usually shipped in bulk and stowed accordingly onto the vessel’s designated cargo holds. These steel coils weigh around 40-50 tons. So, before loading, it must be ascertained that: 

• The holds are swept, cleaned with fresh water and dried thoroughly. All remaining residuals, like rust, debris, flakes, and other contaminants, should be removed. Also, any remaining gases must be stripped off the holds before loading. Per regulations, a ‘cleaning certificate’ should be obtained from third-party providers after the cargo hold cleaning process. 
• Pre-loading surveys of the steel coils are essential.
• Assessing the integrity and water tightness of the cargo hold, the integrity of the hatches and openings, and ventilation and loading cranage systems.
• A thorough inspection of the cargo holds and carefully marking sharp edges or points. 
• Ascertaining the presence of loading and securing manuals with a suitable loading plan. Though, for all practical purposes, as per SOLAS VI regulations, securing manuals should be present for all types of cargo, steel coils are not specifically under any form of definite framework. So, it is the responsibility of the operator and freight managers to ensure that they are stowed safely, securely, and adequately, and optimising the maximum amount of space available. 

Loading and Unloading Procedure

The loading process is carried out meticulously with the help of cranes and derricks, both on-board and those present in the cargo terminals or ports. The coils are usually lifted through their geometric centre, where the suspension point is typically braided steel wire wraps or slings. Tying chains are avoided to prevent damage to the steel surface.

A maximum level of care is taken to ensure that the coils remain unharmed and are unscathed on their surfaces (especially cold-rolled and finished ones). When these coils are handled using forklifts, round or circular lifting section tines are used as conventional rectangular ones with sharp edges, which can harm steel surfaces or distort the coil centre. 

Coils are always placed such that they are axially oriented with the longitudinal direction of the ship; that is, their circular centroid always faces the fore-aft direction of the vessel. 

They are permanently wedged at the bottom in a transverse direction to prevent rolling motions and damage. To avoid damage to the steel surface and ensure sufficient friction to stop the coils from rolling, they are usually placed on wooden planks arranged in the transverse direction, known as dunnages. 

They are usually about 25-30 mm thick and act as an intermediate layer between the coils and the ship’s plating. Furthermore, they can absorb a significant amount of the structural loads from the coils before they are uniformly distributed over the vessel’s structure. 

These dunnages are carefully dried beforehand to ensure that any form of moisture that can pose a risk of causing rusting and corrosion to the steel coils are absent. The securing wedges, in turn, are further pinned to ascertain that any motion present in the coils during the voyage is arrested, and the resultant dynamic loading is transferred to the vessel’s structure.

For all practical purposes, the loading coils are always placed in designated cargo holds and never on the deck or any other part above the strength deck. The loading is done accordingly to ensure optimal space utilisation but not abnormal or non-uniform loading of the coils.

Furthermore, the dunnages are also carefully placed in a way such that the weight of these coils is not transferred to unstiffened spans of the plating (that may result in localised static, dynamic and fatigue loads) but on the bottom shell plating or inner bottom plating (for double bottom vessels) as a whole as line-distributed loads where the maximum amount of loading is tended to be enacted on the stiffening and deep members. 

On the flip side, this is problematic as this causes the overall loading to not comply with the loading information specified in the information and cargo guidance manuals. But for all practical purposes, the steel coils are usually carried on large bulkers or other general-purpose carriers that are adequately strengthened and have high design load values. 

Similarly, during unloading, the wedges and lashings are all unlocked carefully, and the coils are lifted by cranage equipment one by one starting from the topmost layer in a fashion similar to that of loading. 

Stowage and Securing 

After loading the steel coils, stowage and securing is another essential aspect. Steel coils vary in size and weight. So, from the first principles, their stowage philosophy is the same as any other form of cargo. They are stowed in the lower holds and loaded from bottom to top for a more significant number of such oils.

 To keep the centre of gravity below feasible limits of vertical position, the heavier coils are loaded first and kept at the bottom regions and the lighter or smaller ones at the top. The coils are strapped or banded to one another using suitable securing arrangements. 

They are positioned in athwartships and in multiple tiers or levels for a greater number of coils. Between two successive layers, the coils are strapped to each other. For multiple rows of coils stowed, there is a minimum clearance of 4 to 6 inches between two rows to avoid contact forces and any damage during loading and unloading procedures. 

A central coil, also known as the key coil, is chosen in a central location both in a horizontal and vertical sense, with steel strappings directed to both the adjacent and the steel coils situated below. 

The strappings are hard metallic, are in taut conditions, and are often pneumatic in modern arrangements. Any key coil resting on a bottom layer of coils is lashed and positioned. 

The bottom edge of the diameter is below the top tip of the bottom coil by at least one-third of the geometric diameter of the latter; however, it should not exceed 60% of the diameter of the top or key coil. 

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• Difference Between Lifeboats and Rescue Boats
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• What Is Moulded Depth Of A Ship?
• Understanding The Beam Of A Ship

Disclaimer: The authors’ views expressed in this article do not necessarily reflect the views of Marine Insight. Data and charts, if used, in the article have been sourced from available information and have not been authenticated by any statutory authority. The author and Marine Insight do not claim it to be accurate nor accept any responsibility for the same. The views constitute only the opinions and do not constitute any guidelines or recommendations on any course of action to be followed by the reader.

The article or images cannot be reproduced, copied, shared, or used in any form without the permission of the author and Marine Insight.

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Nautical fiction and other adventure stories are often filled with horrifying instances of ships being stranded at sea- due to storms and technical failures- not knowing the right direction. It’s true that navigation in the open ocean is significantly difficult, unlike on land.

The sea, with its vastness and unpredictable chaos within, always offers an uncertain journey for the captain and other sailors.  For navigators, while the land provides several fixed visible cues in the landscape, the sea does not leave any useful, distinguishing features.

Due to this complexity, marine navigation has evolved significantly since the origin of humankind, finding various methods and measurements to save the life of mariners embarked on sea travel.

For many, the first encounter with the measurements being followed at sea raises eyebrows, wondering why they need to differ from miles and kilometres used while talking about land. Unlike measuring distance and speed on the ground, sailors use nautical miles and a knot for measurements during the sail.

At sea, in navigational calculations, the statute mile is considered an arbitrary length of no particular significance. And in particular, the replacement of the ordinary measurement with nautical miles and knots at sea helps the Mariners to read charts that use latitude and longitude quickly.

Currently, the nautical mile developed from the geographical mile is used as the unit of measurement by all countries for air and sea navigation. It is also used in treaties and International law to define the limits of territorial waters.

What is Nautical Mile?

A nautical mile, a unit of measurement defined as 1,852 metres or 1.852 kilometres, is based on the earth’s circumference and is equal to one minute of latitude.

A mile on land equals 5280 feet, while a nautical mile equals the one-sixtieth degree of latitude. It varies from 6046 feet on the Equator to 6092 feet at a latitude of 60°. This difference occurs as the earth is not a perfect sphere but an oblate spheroid.

If one is to pick a part of the earth after cutting the planet in half at the equator and consider the equator as a circle, it can be divided into 360 degrees.

Then, one degree can be split into 60 minutes, of which one minute of arc on Earth is one nautical mile. One nautical mile is slightly more than a statute mile (1 nautical mile = 1.1508 statute miles).

According to the English measurement system, a nautical mile equals 1.1508 miles or 6,076 ft.

What is Knot?

Then comes the knot. Of course, we are not talking about sailing knots, such as Figure-8 Knot. A nautical knot is a unit of speed equal to one nautical mile per hour (1 knot = 1.15 miles per hour) or approximately 1.15078 mph.

Similar to the speed and distance measurement on land, the nautical mile and knot explain the movement of a vessel at sea. For instance, a boat or ship travelling at 15 knots could go 15 nautical miles per hour.

History of Maritime Navigation

Since the beginning of ocean navigation, several methods have been used to make age through long and vast seas easier. Many traditional practices, using geometry, astronomy and even special instruments, helped sailors navigate their destinations.

In ancient times, long before the ship’s clock became common, sailors relied on time derived from the position of the sun, moon, and stars- now known as Celestial navigation.

Sometimes, in addition to their know-how, luck protected them when they ventured out into the uncharted, dangerous waters.

In the later periods, the mariners succeeded in developing charts depicting distant shorelines and common features of the sea during voyages. According to historical records, such charts produced in the earlier period were marked with simple outlines of coastlines to support written or oral directions.

In addition, compasses, astrolabes, and callipers were ocean navigators’ tools in earlier times. The Mariner’s Compass, one of the earliest navigational tools and an early form of the magnetic compass, had been used widely in earlier periods.

Primarily, this compass was used to determine the direction of the wind when the sun was not visible.  Similarly, the cross-staff, astrolabe, and quadrant were in use to help sailors choose latitude in several stages of maritime navigation.

Phoenicians are the first Western civilization to have developed the art of navigation at sea thousands of years ago. Phoenicians relied on primitive charts and observations of the Sun and stars to navigate their vessels to destinations.

In the later period, the Phoenicians and their successors, the Carthaginians, also invented a tool known as the sounding weight. Made of stone or lead, this bell-shaped tool had a long rope attached to the tallow.

Sailors used to lower this weight into the bottom of the sea to determine how deep the waters were and, using this measurement, to estimate how far they were from the land.

In addition, the tool, with the help of the tallow inside, could pick up sediments from the seabed, which enabled expert sailors to decide the location of their vessel.

However, centuries passed before using a standard method to measure the distance and speed during navigation at sea. Many new techniques and methods were experimented with from time to time, making marine navigation more meaningful.

Until the fifteenth century, coastal navigation was mostly practised since the open sea voyages were limited to regions of predictable winds and currents. On the open sea, mariners mainly depended on dead reckoning— calculating one’s current position using a ship’s last position, speed, and direction.

Further ventures by the sailors were enabled by developing scientific and mathematically-based methods and tools in the following years.

The invention of the sextant, the chip log Chronometers, etc., made the calculation of latitude and longitude possible and much easier.

And the modern era saw the replacement of ancient navigational tools with electronic and technological equivalents and the determination of standard measures, including the Prime Meridian.

Marine navigation has become more systematic and easy with the help of new technologies, from Gyroscopic Compass to GPS.

History of Nautical Mile and Knot

Years after using several techniques to determine the position and speed of a vessel, British mathematician Edmund Gunter succeeded in enhancing navigational tools, including a new quadrant to define latitude at sea. Gunter claimed that the lines of latitude could be used as the basis for a distance measurement unit.

Eratosthenes and his successors had already assessed the circumference of the Earth, helping other mathematicians to build on it. Gunter proposed the nautical mile as one minute or one-sixtieth (1/60) of one degree of latitude (one degree is 1/360 of a circle, one minute of arc is 1/21600 of a circle).

Using the circumference of the Earth assessed by Dutch scientist WillebrordSnellius aka Snell- who assessed it at 24,630 Roman miles or 24,024 statute miles -Gunter defined a nautical mile as 6,080 feet (1853 meters), i.e. the length of one minute of arc at 48 degrees latitude.

Even decades after these developments, there was no standard definition of a nautical mile, and different countries had different definitions to follow until 1929.

In 1929, Monaco’s First International Extraordinary Hydrographic Conference accepted the international nautical mile as precisely 6,076 feet (1,852 meters). This standard definition of a nautical mile in use is accepted by the International Hydrographic Organization and the International Bureau of Weights and Measures.

The United States measurements were based on the Clarke 1866 Ellipsoid, and based on this calculation, a nautical mile was 6080.20 feet (1,853 meters).

Similarly, the United Kingdom defined the nautical mile based on the knot- unit of speed measured by dragging pieces of knotted string.

According to this, one knot was defined as one nautical mile, and one nautical mile represented 6,080 feet (1853.18 meters).  However, the US and the UK abandoned their definitions in 1954 and 1970 and accepted the international measure of a nautical mile.

On the other hand, the term knot can be traced back to the 17th century, during which sailors used a device called the common log to measure the ship’s speed.

The common log was a device consisting of a wedge-shaped piece of wood and a coil of rope with uniformly spaced knots attached to the piece of wood.

During the sail, the piece of wood was allowed to float for a specific time after lowering from the back of the vessel, and also, the line was allowed to play out freely from the coil as the wood floated.

After some time, the line was pulled in, and the sailors used to count the number of knots on the rope between the ship and the wood to measure the speed of the ship.

Sailors concluded the vessel’s speed according to the frequent average measurements taken throughout the day.

With the help of advanced technologies, the knot measurements are determined using mechanical tow, Doppler radar, and GPS.

Calculation of Nautical Mile and Knot:

The nautical chart turns out to be one of the essential elements abroad the vessel once it sets sail. The fixed relationship between distance, speed and time helps sailors calculate the distance the ship is expected to travel in a given time.

The formula sailors use is 60 x D = S x T, which is expressed as 60D = ST.

Conversion of Kilometer to Nautical Mile  – Formula

Check out the video for understanding the formula for conversion of a kilometre to a nautical mile.

Frequently Asked Questions

1. Why is a nautical mile different from a mile on land?

Nautical miles are used for measuring the distance travelled through the water. A nautical mile is a little longer than a mile on land. The difference arises as the earth is not a perfect sphere and is slightly flattened at the poles. A nautical mile is based on the earth’s longitudes and latitudes. Hence, one nautical mile is equal to one minute of latitude.

2. Is the nautical mile the same as the air mile?

The term air mile is internationally defined as a nautical mile. It is equal to 6076 ft or 1852 m. Hence, 100 air miles equal to 115.08 statute miles or 185.2 km.

3. Why is the term knots used?

The knot was a term earlier used as a length measure on the vessel’s log lines, which were used to measure the speed of a ship on the water. This line was marked at intervals by knots tied in the rope.

4. Why do sailors use knots?

The simple answer is that knots are easier to navigate since, unlike land miles, they are based on the earth’s degree of latitudes. One nautical mile is equal to one minute of latitude.

5. How many nautical miles can a ship travel in a day?

On average, sailboats can travel up to 100 nautical miles or 185 km in 24 hours when they sail downwind. If the engine is running, they can cover around 130 nautical miles in case of long journeys.

You might also like to read

• Nautical Law: What is UNCLOS?
• Annual Summary of Notices to Mariners: What is NP 247(2)?
• A Guide to Handling Garbage on Ships
• 5 Terms Every Mariner Should Know Under UNCLOS
• Audacious Open-ocean Ambush of Product Tanker in the Gulf of Guinea
• 10 Ships Sunk By Accident with Iceberg

Disclaimer: The author’s views expressed in this article do not necessarily reflect the views of Marine Insight. Data and charts, if used in the article, have been sourced from available information and have not been authenticated by any statutory authority. The author and Marine Insight do not claim it to be accurate nor accept any responsibility for the same. The views constitute only the opinions and do not constitute any guidelines or recommendations on any course of action to be followed by the reader.

The article or images cannot be reproduced, copied, shared or used in any form without the permission of the author and Marine Insight. 

Why Nautical Mile and Knot Are The Units Used at Sea? appeared first on Marine Insight - The Maritime Industry Guide

CONEX containers are one of the most iconic developments in the history of transportation and logistics, as they revolutionized the shipping industry.

These containers gave rise to the industrial intermodal standard containers known today as TEU and FEU.

Intermodal containers can be transported using road, rail and maritime methods. In some instances, they can also be transported by air when the aeroplane stowage systems are modified to accommodate their specific dimensions.

The term CONEX is an abbreviation of Container Express, indicating that transport times were cut short by having a single container compatible with multiple means of transport.

History of CONEX Containers

During the wars in Korea and Vietnam, US troops needed quick methods of ferrying supplies to the soldiers at the front lines.

The issue was that goods loaded on container vessels had to be reloaded onto trailers for road transportation. This presented a logistical challenge, as valuable time was spent in the transfer process.

A unique design known as the CONEX box was developed to overcome this. This box was compatible with the trailers on which they could be carried.

In addition, they had locking mechanisms that could connect adjacent boxes to prevent toppling over during transport. The first model of these intermodal containers was the “Transporter” used in deployment during World War II to ferry supplies to the war front.

The basic design had a 4,000 kg weight limit and was made of corrugated steel to serve as protection.

Related reading: How are shipping containers made?

Further technological advances allowed skids and lifting mechanisms to be attached to the early designs. These ensured that the containers snugly fit during transport and that they could be easily picked up by cranes and loaded onto trailers.

During the Korean war, containers were modified to store larger quantities of goods without compromising structural integrity. The Vietnam war witnessed larger CONEX boxes being developed that could double up as living quarters during harsh conditions.

During transport, they could be stacked three containers high and were lashed together to prevent accidents.

The modern intermodal containers were developed from the rudimentary CONEX boxes by American trucking magnate and businessman Malcolm McLean, who revolutionized the transport industry.

CONEX containers are still in use by the US military but have been renamed BICON, TRICON and QUADCON containers. These containers are unique to military usage and vary in dimensions from the standard intermodal containers.

Dimensions of CONEX Containers

The generic sizes of the CONEX containers have varied over time to suit the various types of cargo it has been used to accommodate. During the wars, the early model known as the “Transporter” used for moving supplies was 8 ft 6 in long, 6 ft 3 in wide, and 6 ft 10 in tall.

Half units of smaller dimensions, 6 ft 3 in long, 4 ft 3 in wide and 6 ft 10 in tall, were used in shipping where space constraints were present.

The modern CONEX containers have standard sizes in the Twenty-foot Equivalent Unit (TEU) and Forty-foot Equivalent Unit (FEU).

Related Reading: Different types of shipping containers

As the names suggest, these containers are respectively 20 and 40 feet long and are intermodal. To ensure compatibility and even spacing on ships and trains, the width and height are fixed at 8 ft and 8 ft 6 in, respectively.

For larger space requirements, high cube or hi-cube dimensions are used. These are the same length and width but are taller than conventional containers at 9 ft 6 in.

Along with these standards, more unusual sizes are also in circulation, such as the 10 ft, 25 ft, 45 ft, 48 ft and 53 ft long containers.

Certain types of cargo require compact or larger storage spaces, so they utilize these types of shipping. The volume loading capacity of these containers can vary as 33,000 litres for the TEU containers, 67,500 litres for the FEU containers or 75,300 for the FEU hi-cube variant.

The maximum gross weight permissible on board these containers is 30,000 kg for the TEU and FEU sizes, while it goes slightly up to 31,000 kilograms for the FEU hi-cube size.

On average, the weight of the empty containers ranges between 2,200 for the TEU and 3,800 kg for the FEU.

Features of CONEX Containers

The distinguishing features of the CONEX containers that set them apart from the older variants of the container industry were their superior safety, strength and compatibility.

These containers were built out of corrugated steel sheets and could withstand sufficient forces and strains before crumpling. In addition, a specialized locking mechanism was in place that prevented the theft of the goods inside.

Certain containers required windows and additional entryways. In such cases, a common double locking mechanism in modern-day containers was put in place to secure the doors.

Also, steel bars and bullet-proof glass were used on windows to prevent theft. The strength of these containers came from the corrugated shape, which increased the maximum bending stress along the axis perpendicular to the shape distortions.

A vital feature of the CONEX containers was the interlocking mechanisms present on the exterior. For instance, the early designs had skids on the bottom that could fit perfectly over containers below it.

With advances in manufacturing, the containers could also be locked to the adjacent storage units.

For this purpose, a specialized mechanism was used to connect the bottom of two adjacent units, which could be released as and when needed.

In addition to all these features, safety and administrative laws could now be easily applied, as a uniform standard was used for all the containers shipped across the world.

Uses of CONEX Containers

CONEX containers can be used for various purposes, differing based on the type of goods they house within themselves.

General purpose dry containers can ship cartons, pallets, drums and boxes. They are apt for transferring similar types of dry goods.

They can include unique mechanisms built for particular goods that can be difficult to load into the container. For instance, garments that cannot be folded and transported are stored on hangers and shipped using garment containers.

Along with garments, storing heavy pallets is difficult since cranes can often not be used to directly place the goods within the allocated location in the container.

To solve this issue, rollers on the container floor are used to shift the goods quickly. Large cartons and pallets can be loaded in this manner, using only limited personnel to load goods into the container.

For transporting liquids, powders and gases, tank containers are commonly used. These consist of multiple pressurized tanks stored in the container such that large quantities of fluids or powders can be shipped.

For cargo such as toxic gases, or poisonous liquids, special signs are installed at the doors and on individual tanks to prevent accidents and mishaps. Along with pressure regulation, certain gases must be maintained at specific temperature and humidity ranges.

Here, temperature-controlled containers can be put to use. These include insulated containers maintained at a constant temperature through refrigeration or heating. These are also ideal for perishable goods such as fresh foods, especially meat.

Thermally insulated containers can also be used with the same features for dry goods that have to be kept under specific storage conditions. In addition, ventilated containers are also available. These have unique mechanisms for active ventilation (using a pump system) or passive ventilation (using air drafts through ventilation holes in the container) that ensure goods reach their final destination in the right condition.

Another common method of transporting goods, especially loosely stored items or powders, is using bulk containers. Similar to bulk carrier vessels, these containers are rigid on all four sides and at the bottom. However, the top is sometimes made separately or with specialized gaps for loading loose items. This includes large-scale shipping of powders, grains, and loose materials such as ores and rocks.

For a fine matter that can easily be lost if not stored properly, movable bins are used to collect the material. Once filled, the individual bins are loaded onto the containers and stacked along the entire length. These bins are handy, as they allow companies to roll on directly and roll-off goods during loading and unloading operations.

It removes the need for specialized pumps or motorized mechanisms to unload the goods at the destination. For such containers, the top is often removable or made of flexible material with a slit that allows factories to load material without the danger of spilling directly.

Another type of container similar to the one previously discussed is the open-top container, which can be used to store large objects that would have otherwise required the container to be dismantled. This is ideal for large machinery that must be loaded through the top.

The difference between the open-top and bulk containers is that while bulk containers can have removable lids, the open-top ones often do not have a roof for the containers. The benefit is that multiple containers can be stacked and used for transport with minimum modifications for massive objects.

To stack these containers, the bottoms are removed for certain ones, and the object is placed in the stack using specialized cranes at dockyards. Open-side containers can be used to slide objects into the container without having any issues with loading. In addition, having open sides can aid in ventilating the goods stored within. This is ideal for perishable foodstuff such as potatoes and apples that will be able to withstand the journey without extra protection.

Frequently Asked Questions

1. When was the Conex container first invented and used?

It was developed during the Korean war and used to transport and store war supplies during the Vietnamese and Korean wars. It was reinvented by Malcolm Mclean, who gave it the form of a standard intermodal shipping container, used widely by shipping companies today.

2. Why are they named Conex containers?

They were extensively used during war times. This logistics method was called Container Express, hence the name Conex. They are also called intermodal containers due to their ease of transport from one destination to another.

3. How much does a 40ft Conex cost?

A 40ft high cube container will cost an average of 5,320 US Dollars. Although, a 20ft reefer container would cost 12,800 US dollars.

4. Are Conex boxes waterproof?

A seaworthy Conex container is watertight. It has rubber seals around its doors to keep the seawater, including rain, out of the interior. A waterproof container can lock and hold a liquid inside without spilling it.

5. Is Conex the same as a shipping container?

Whether we call them shipping containers or storage containers, Conex or Conex boxes, or ISO boxes, they all mean the same thing. They are large metal boxes for transporting goods at sea.

You might also like to read

• 16 Types of Container Units and Designs for Shipping Cargo
• Flat Rack Containers – Types, Specifications And Dimensions
• What is TEU in Shipping – Everything You Wanted to Know
• How to Plan Cargo Containers Stowage on Container Ship?
• Case Study: Loss Of Cargo Containers From Container Ship “Ever Smart”

Disclaimer: The author’s views expressed in this article do not necessarily reflect the views of Marine Insight. Data and charts, if used in the article, have been sourced from available information and have not been authenticated by any statutory authority. The author and Marine Insight do not claim it to be accurate nor accept any responsibility for the same. The views constitute only the opinions and do not constitute any guidelines or recommendations on any course of action to be followed by the reader.

The article or images cannot be reproduced, copied, shared or used in any form without the permission of the author and Marine Insight.

What Are CONEX Containers – History, Dimensions, Features And Uses appeared first on Marine Insight - The Maritime Industry Guide

When one travels by ship, the ship’s windows are the most important and striking feature on a ship’s side. The ship’s windows are known as portholes, shortened form of the word ‘porthole window.’ Portholes, however, are also not just a part of ships but are found in submarines, airplane and spacecraft.

Sometimes ship portholes are known as ‘side scuttles’, mainly because they are located on the side of a vessel. Today, they come in different styles to match a ship’s interior design. Sometimes they are used as a frame or a decorative piece on a small boat or a yacht.

Understanding Ship Portholes

Portholes have been a part of ships since the beginning. They have retained their circular form and are unique compared to windows in other means of transportation.

The portholes are designed so that when a ship cruises into the middle of the seas, one can get the best possible ocean view from the ship’s porthole. For this, the height of the portholes is strategically decided, and one end of the portholes is hinged.

A porthole was initially constructed to be a window in those areas of the ship where airing was a significant problem. This allowed light and fresh air to enter those parts. This construction pattern immensely helped the people working in these areas to work continuously for long hours. However, later on, portholes came to be built on every room and cabin on the ship.

Construction of Portholes

The materials used for building ship portholes are stainless steel, aluminium, brass, bronze, and iron. The glass used in the portholes is compulsorily made involving sand. Making glass is known as sand-casting; silica sand is the primary material for this process. To make the glass, a mixture of silica, lime and ash is mixed, heated and cooled until the right consistency of glass is achieved.

The process further involves constantly re-heating the mixture in huge furnaces so that the glass reaches its appropriate thickness. Then this mixture is laid on top of a melting tin, ensuring that the proper shape of the glass is achieved. The glass is finally cooled. This process is called tempering, providing the glass does not break or shatter.

Materials such as brass and bronze are preferred over iron and steel because iron rusts because of seawater, and steel bends after a certain period. Brass portholes and bronze remain effective for a longer time.

The glass is put in a metal cover or steel frame with a shaft or screw to keep it firm. Hence, the watertight glass cover protects the ship windows from breaking or damage.

A ship’s porthole measures around two feet in diameter, while its weight can go up to around 100 pounds. Ship portholes are generally because of the durability factor. They offer resistance not only from sunlight but also from sea and rainwater. The heaviness of the ship’s portholes also ensures that no damage is caused at any time on the boat.

Portholes have become quite trendy. One can find numerous antique maritime portholes for decoration purposes. But just because of their utility, they are still used extensively on ships worldwide.

Frequently Asked Questions

1. What is a porthole?

A porthole is a small circular opening or a glass window in a ship, aeroplane, submarine or spacecraft. They are bound in a frame and allow one to see outside.

2. Why are ship portholes round?

A round shape is preferred to maintain a vessel’s structural integrity. Oceans and seas put immense pressure on the ship’s body, and square or rectangular windows are more susceptible to stress and might become weak at the corners. A circular window is tougher and also suits the overall design.

3. How thick is porthole glass?

Portholes have a varying range. Some are several inches to over two feet and weigh from several pounds to more than a hundred pounds. Much of their weight is of the glass, which should be less than two inches thick for safety purposes.

4. What are the materials used for making portholes?

Uusally, materials like stainless steel, brass, bronze, iron and aluminium make ship portholes. Also, the glass used for making portholes is mandatorily made of sand, and the process is called sand-casting. The primary material used in this process is silica sand.

5. Can one open a porthole on cruise ships?

The word port is derived from the french word Porte, meaning door. In today’s cruise ships, most portholes only open slightly, and the others are usually built for design and for letting natural light inside.

You might also like to read-

• 10 Points To Check While Inspecting Accommodation Areas On Ships
• What is Maritime English and Why Is It Important?
• Different Systems on a Naval Submarine
• Maritime Accidents: The Sinking of Britannic Hospital Ship
• What are Rogue Waves?

Disclaimer: The authors’ views expressed in this article do not necessarily reflect the views of Marine Insight. Data and charts, if used, in the article have been sourced from available information and have not been authenticated by any statutory authority. The author and Marine Insight do not claim it to be accurate nor accept any responsibility for it. The views constitute only the opinions and do not constitute any guidelines or recommendations on any course of action to be followed by the reader.

The article or images cannot be reproduced, copied, shared, or used in any form without the permission of the author and Marine Insight.

What Are Ship Portholes? appeared first on Marine Insight - The Maritime Industry Guide

One of the most important qualities that a marine engineer must have is to know and understand his machinery extremely well. Before breaking down completely, each machinery will show a variety of signs and symptoms indicating the type and severity of the fault.

Along with knowing the right procedures to operate the ship’s machinery, mariners must also know how to identify and troubleshoot any problem in the engine room.

Following are 10 ways in which a mariner can identify and rectify faulty machinery:

1. Abnormal Sound

Sound is by far the most prominent factor which draws seafarer’s attention towards a troubled part or machinery. If you are a good watchkeeper, it will be easy to figure out the difference between normal running sound and problematic sound even when you are not near the machinery. For e.g. A “hissing” sound will indicate leakage, a loud knocking sound will indicate loosen or broken parts, a high wobbling sound will indicate obstruction etc. Unfortunately, there is no guide to learn these sounds. Only through experience can one master such skills.

2. Smell

Another powerful indication, which can be easily detected by human senses, is that of abnormal smell coming from machinery or systems. When you sense heavy/strong smell in the vicinity, it can be due to leakage of oil, fire, effects of high temperature etc. A burning smell near the motor is an indication of an increase in temperature of its coil. You can detect the smell of heavy oil even if you are not able to see it.  Similarly, steam leakage will leave a dampen smell. It’s only while working onboard ships, one is able to know and understand different smells indicating a variety of problems with the machinery.

3. High Vibration

All machinery systems with moving parts generate vibration. One of the most neglected maintenance jobs for machinery onboard ships is that of vibration analysis. Many shipping companies do not include it in its planned maintenance system. Even the timely checks for tightening the foundation bolts for any machinery are not included in the PMS. Every machinery will have its own frequency of vibrations. It is important to keep a track of any increase in the vibration of machinery, which if ignored, can lead to severe damages in the long run. Any change is the vibration of machinery can easily be felt on board ships. This is a sign which should never be ignored.

4. Leakages

Leakages are a result of faulty piping or machinery systems. They are easy to identify onboard ships.  Never ignore leakage from any kind of machinery as it can lead to spills, fire, flooding and other major accidents. If you find oil-water or air leak in the machinery, do try to rectify it immediately or mark it as important to check during the next maintenance schedule depending on its severity.

5. Smoke

Every machinery with a combustion chamber can be judged for its performance by checking the exhaust smoke for its colour and density. Exhaust smoke of Main Engine, Auxiliary Engine, boiler etc. to be monitored for knowing the combustion process. Black smoke indicates a problem in the fuel injection system and improper combustion (lack of air etc.) whereas white smoke indicates water ingress in fuel.

6. Abnormal Parameters

Abnormal or fluctuating parameters are mainly related to machinery faults. It’s important to keep a track of all machinery parameters onboard ships by comparing the readings in the logbook to the data of previous dates. While taking rounds, any deviation in the parameters must be taken seriously by taking proper investigation and preventive actions.

7. Alarms

Every alarm indicates a problem, major or minor, onboard ships. They have been installed for that purpose of identifying faults. Never ignore an alarm related to any kind of machinery. An oil mist detector alarm in the main or auxiliary engine, even when other parameters are normal (Crankcase temperature, scavenge temperature etc.), must be taken seriously. Many incidents have been reported for crankcase explosion when OMD alarm has sounded but the crew ignored it seeing other parameters are normal.

8. Observing Problems in Connected Systems

In the ship’s engine room, most of the systems are connected to any other form of system or machinery. If a problem is observed in one system, do check the other machinery connected to it. For e.g. When there is a problem in the expansion tank level suddenly going down, do check any leakage in the main engine, generator, or air compressor connected to it. A leakage in jacket water of the engine will lead to air going into the expansion tank with high pressure during the compression stroke and emptying the expansion tank from the vent or other openings.

9. Change in Amperage

More than 80% of the machinery on a cargo ship are electrically operated i.e. from ship’s generated power.  Ensure to check the current of all the electrical operated machinery and pumping systems. A high current for a purifier indicates a problem in the clutch drum or transmission gear. Similarly, high auxiliary blower current indicates the scavenge pressure inside the engine is more than that supplied by the fan. Since in most ships, the auxiliary blower fans are operated manually, the fan must be switched off when the pressure is reached or when the current crosses the marked limit.

10. Knowing Your Machinery Inside-Out

Last but not the least, knowing your designated machinery inside-out will help you identify the minutest change in its performance. Learning about its history, reading its maintenance reports, and keeping routine checks will give you an idea as to how your machinery acts and performs under different conditions. This would make it easy for you to recognize any fault in your machinery system when it operates differently from its usual working pattern.

Identifying machinery faults is an art which comes with practice and experience. Do you know any other important methods to identify machinery problems?

Disclaimer: The authors’ views expressed in this article do not necessarily reflect the views of Marine Insight. Data and charts, if used, in the article have been sourced from available information and have not been authenticated by any statutory authority. The author and Marine Insight do not claim it to be accurate nor accept any responsibility for the same. The views constitute only the opinions and do not constitute any guidelines or recommendation on any course of action to be followed by the reader.

The article or images cannot be reproduced, copied, shared or used in any form without the permission of the author and Marine Insight.

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There are times when the paperwork seems endless and a condition of mental boredom and of being non-complacent props out of most of us. But the fact of the matter is that shipboard record keeping is here to stay. So in continuation to the previous list of logbooks that are required to be maintained legally and legibly onboard, let’s take a look at a few more logs that require the ship officer’s attention.

Medical log

This log goes unattended to at times. Non-complacency and avoidance are the two known major factors for the medical documentation not being up to date. It’s well understood that the ship’s officers are no more than passive first aid providers. This should be all the more a reason to understand medicine to an extent where proper aid could be given at the right time. This being obvious, the aid provided must be documented in the statutory log provided onboard. Being at sea makes the seafarers helpless. Hence it’s imperative that, atleast, the medical paperwork is updated with accurate or best known details of the following.

1. Entries should mention under what circumstances the medical aid was provided. The nature of the injury or illness, their treatments and progress (if any) must be mentioned to the best knowledge.

2. Recording even a simple dosage of a pain killer or even an anti-inflammatory drug is vital.

3. The medical log may have an inventory list of the drugs onboard attached to it for easier reference.

4. Master or an Officer designated for upkeep of the medicines is the only personnel onboard to oversee medical related issues onboard. Entries should be made without delay with signatures, both of the patient and of the medical provider. Master to endorse the same.

5. Apart from this being a legal obligation, recording of injuries and illnesses aid the owners and the P & I Clubs for settlement of further claims. This in turn enables the Master to defend himself and his owners against later claims and allegations made by the then injured/sick seafarer.

GMDSS Radio Log

A Radio log with adherence to the SOLAS Ch V and Merchant Shipping regulations is required to be maintained onboard most merchant ships / vessels. It should be retained onboard on the navigating bridge well-situated near the radio equipment. Again, it is liable for compulsory examination during surveys.

The person designated for the radio record keeping, generally the senior navigating officer or radio officer (if onboard) is sole responsible for its upkeep. Like all official logs, this one too comes with a leaflet of instructions on how to enter the details, but personally, I have seen people making ambiguous entries for even simple operations such as testing the radio equipment for example. Anyway, let’s try to clear the air for some:

–  As most logs, the ship’s particulars are entered as required. But one has to also update the details of the existing radio operators every time the officers change hands.

–  A synopsis of all interactions/communications related to Distress, Urgency or Safety must be entered clearly along with the ship’s position, date and times. All the follow-up communications, actions taken by the vessel, etc. must be recorded as evidence to the events that followed over radio. One must not forget recording the SSB / VHF radio frequencies over which the communications took place.

–  Breakdown or malfunctioning of the radio equipment, breakdown of communications with coastal or land earth stations must be logged down to ones best knowledge. This saves the day for any inquiries propping up on related issues.

– Where testing of the equipment is concerned, details must be provided to the ‘T’. This means, even if the receiving stations could not respond or acknowledge back an entry should be made along with the frequencies over which the radio equipment was tested and if calling out a coast or a land earth station, details of such station to be recorded. If the testing is carried out on batteries only (which normally should be the case) then such details must be logged.

–  Entries of the vessel arriving and departing port are also noted.

–  It is required by the flag to log and attach hard copies of Distress, Urgency, Navtex, EGC, NBDP, DSC, etc. convenient to the entry made in the book.

Ship Security Log Book

Security of seafarers has been a hot topic lately. Considering all the security measures that are taken by the vessels as precautionary, record keeping has become all the more tedious. The ship security officer is the one responsible for the log books’ care and upkeep. SOLAS Ch XI-2 provides with all the fundamental obligations the vessel needs to follow on shipboard security. However, let’s take a quick look at the essentials of record keeping for security related matters onboard.

– Firstly one should ensure that an updated list of last 10 calls at port is attached with the log book.

– Other notable entries must include a record that the ship has a valid International Ship Security Certificate and its issuing authority. Having a record of the necessary documents handy enables a smooth inspection process if the vessel undergoes one.

– The current and past onboard ‘Security levels’ (read level nos. 1, 2 or 3 as per SOLAS/ISPS Code) must be recorded along with a brief statement recording the Security level change over position, whether while arriving or departing a port or at sea while transiting through waters infested with pirates that pose a security threat to the ship and her crew.

– All security measures including any additional especially the ship specific ones should be recorded considering that the ship and her crew are vulnerable to security breaches at any point while in port or at sea.

–  Drills, trainings conducted must be logged with a separate sheet containing the names and signatures of the crew participating and the briefing / debriefing details.

The logs stated above are just a few important ones in a sea of log keeping procedures followed onboard. Over the years, ISM has paved the way for better documentation. This has in fact resulted in streamlining record keeping as most of us seafarers are also experienced and competent in following the ISM procedures. Overall, the idea is to not only ‘full up’ the log book, but to ‘fill it up’ with your best known abilities while not straying away from the facts.

You may also like to read – What is Chain Register On Board Ships?

Important Points For Logbook Keeping On Ships – Part 2 appeared first on Marine Insight - The Maritime Industry Guide

Almost a decade ago, when I was sailing on an oil tanker, a young chief officer who had joined my vessel, asked me if the ship was ever going to load in Iraq. When I asked him why he was so curious about Iraq, he innocently replied that since after completion of loading no survey was carried out in the Iraqi port and the Bill of lading was prepared based on figures provided by the ship. The ship would be loaded with crude oil almost 99% full and B/L figures provided by the ship would be 98% or less of the total cargo. The 1 % or more of this cargo would then be sold to small barges off the coast of a maritime nation in the Arabian sea arranged by the installation. The loot would then be equally divided among all on board and ashore. When I informed him that nothing of this sort can happen on board my ship, he was very disappointed and after a few weeks left the ship.

Have you ever faced food problems, salary issues, ship arrests, engine breakdowns, coercion by senior officers and abandonment by ship owners on a merchant ship?

Well these are just a few of the many problems faced by many seafarers on ships worldwide. The main reason behind these problems is greed, which is a worldwide phenomenon. Corrupt Masters, Chief engineers, Chief officers, ship superintendents, acting alone or in collusion with other shore based entities can make life hell for their crew. If the corruption is led by shore managers, then it’s high time you quit the company and report to authorities against such maritime frauds.

So what exactly is maritime fraud and how to detect them?

Maritime frauds can occur anywhere; be it a vessel, a shipping company office or a trading company transporting goods by sea. The list can go on. It necessarily has to involve two or more parties, out of which one or more must have unjustly or illegally succeeded in obtaining goods or services from another party. Since they can happen anywhere, it is important that seafarer is extra careful and do not get directly or indirectly involved in activities or get himself coerced by senior officers in wrong doings that can cost them dearly, both financially as well as to their reputation.

A special watchdog to detect, inform and combat such maritime frauds, International Maritime Bureau or IMB was set up in 1981 as a specialised division of International chamber of commerce (ICC). It is a nonprofit organization. Even IMO in its resolution A 504(XII) (5) and (9) adopted on 20 November 1981, has urged Governments, organizations and interested parties to co-operate and exchange information among each other to combat maritime frauds worldwide. Hopefully seafarers are already aware of the IMB piracy reporting centre based in Malaysia and getting worldwide piracy reports regularly on board. For more details, refer to icc-ccs.org.

Some of these maritime frauds are visible and can be easily detected, whereas others may remain hidden for a long time in the absence of evidence. For example, the easily visible ones on board are: –

1. Master and / or Chief steward manipulating stores and victualling invoices by signing for unreceived goods and sharing the loot with the supplier.
2. Senior deck officer(s) and / or ship’s crew selling ship stores or cargo.
3. Senior ship engineer(s) selling bunkers by signing for more and receiving less on their ships and manipulating the shortage through cargo residues(diesel) on oil tankers.
4. Senior ship engineers agreeing to accept substandard machinery spares.
5. Senior deck officers manipulating B/L figures
6. Ship superintendents acting alone or in liaison with senior deck officers inflating invoices with stores / spares and/or repair work not carried out in repair yards.
7. Cargo surveyors in liaison with senior deck officers, manipulating daily outturn figs to boost their ratings. This is most common on bulk carriers.
8. Agents, stevedores, suppliers, manipulating invoices in liaison with senior officers on board.
9. Ship manning agents manipulating salaries of the ship crew.
10. Ship manning agents supplying uncertified crew on board for less salary, by using fake certificates, CDC etc.
11. Senior officers on board manipulating Oil record book figures to hide deficiency in ship machinery and pumping residues overboard through portable hoses.
12. Senior deck officers manipulating cargo figures on oil tankers and pumping residues(diesel) to bunker tanks in liaison with ship owner, managers.
13. Ship’s crew and/or Master illegally carrying stowaways intentionally.
14. Ship’s crew and/or Master carrying contraband on board.
15. Insurance frauds committed by ship owners/Managers by manipulating ship records in liaison with ship officers and Master, which may include death on board (Homicides shown as suicides)

I can go on but in their own best interest, seamen should remain vigilant and watchful and identify several other such frauds not reported in this article and bring them to the notice of the port authorities. Whistle blowers are rewarded handsomely these days as it happened in the case of a 3^rd Engineer who provided substantial evidence to the US coast guard many years ago, of wrong doings by a chief engineer, causing environmental pollution. While a long prison sentence was awarded to the Chief engineer, the junior engineer was awarded with a million dollars and US citizenship.

Seafarers have many choices today to collect evidence against frauds committed on board. One of them being an Intrinsically safe camera for hazardous environment and various spy gadgets for indoor use. From false bottoms and incorrect sounding tapes provided by bunker barges to Bunker delivery notes and various stores /provisions supplied to your vessel, vigilance and alertness can prevent many frauds being committed. Never get blackmailed or coerced by seniors for environment related issues. Report quality issues and shortages to the master and 2 or more crew should counter sign all the invoices received on board. Speak freely about safety issues in your monthly safety meeting. Lastly report suspicious behaviour of any crew to your senior officer.

It is important to remember that if the fraud is happening on board, ignorance of any kind is not helpful. By virtue of crew’s presence on board, it is taken for granted that an event has taken place under the full knowledge of the Master or crew or both unless reported by either of them well before they are detected by authorities. The biggest reason for such frauds is mainly Greed, but a maritime fraud will also take place due to coercion of the crew, by senior officers or external person or persons and of a Master by either his own company officials, ship owner, agent, port authorities and criminal syndicates.

Over to you..

Have you ever personally found out about a maritime fraud on board ship?

Let’s know in the comment below.

Disclaimer: The authors’ views expressed in this article do not necessarily reflect the views of Marine Insight. Data and charts, if used, in the article have been sourced from available information and have not been authenticated by any statutory authority. The author and Marine Insight do not claim it to be accurate nor accept any responsibility for the same. The views constitute only the opinions and do not constitute any guidelines or recommendation on any course of action to be followed by the reader.

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What Are Common Maritime Frauds And Illegal Activities On Board Ships? appeared first on Marine Insight - The Maritime Industry Guide