Types of Ships in Merchant Navy

Merchant Navy Ships transport a wide range of goods and people to different corners of the world. Effective shipping and supply chain management have ensured that goods produced in one part of the world are available at the other end of the planet.

However, this would not be possible without different types of ships in the merchant navy, such as container carriers or oil tankers, which are designed to carry specific types of cargo. Some ships, such as icebreakers, are designed to meet the harsh conditions of particular regions.

Economic factors are key to designing a merchant ship since every shipowner wants a maximum return on their investment. Future adaptability is also considered.

Ships are classified based on cargo capacity, size, and weight. Other factors influencing their design, length, and breadth include the canal locks they may have to cross, the water depth in a canal, and the ports they visit regularly.

Height is a constraint if the ship operates in a region with many bridges. Hence, ships are custom-built for the particular trade they would be involved in, the type of cargo ( oil, bulk, containers, etc) they would carry, and the region they would ply in.

The vessel’s preliminary design outlines its dimensions, stability, displacement, propulsion, hull type, general arrangement and structural information. All these parameters are decided according to the ship type.

The different types of Merchant Navy Ships will be discussed in this article.

Cargo Ships

Cargo ships or freighters are merchant navy ships that carry the majority of maritime trade. They are usually constructed depending on the cargo type and are of different sizes.

They are of 7 kinds and may have cranes and other equipment to help with loading and unloading operations.

Cargo ships include general cargo vessels, feeder vessels, container ships, bulk carriers, dry bulk carriers, tankers, multi-purpose ships, reefer vessels and RORO vessels. We will explore all these categories.

General Cargo Vessels

According to Wartsila, a general cargo ship has one or more decks and can carry different goods in boxed, refrigerated, or palletised form. It can also carry bulk materials like grain. However, it usually carries packaged items such as food, machines, motor vehicles, military vehicles, footwear, and garments.

Container Ships

Container Ships or Boxships transport their cargo in massive intermodal containers built for this purpose. These vessels carry most of the non-bulk cargo.

This process is known as containerisation, and container ships, among the largest ships, are used mainly on liner routes. They transport manufactured products and are of standard dimensions.

Containers are placed or stacked on these ships using special cranes. There are refrigerated container ships, too, which can accommodate perishable items like fruits, vegetables, seafood, etc, in refrigerated containers.

They are of different types based on their sizes, such as

• Panamax container ships
• Suezmax ships
• Post-Panamax
• Post-Suezmax
• Post-Malaccamax

Bulk Carriers

Also called a bulker, this ship is built to carry massive quantities of unpacked or loose cargo in its holds. These ships usually carry grains, cement, steel, coal, ores, etc.

The first specialised bulker was constructed in 1852, and since then, the number, size, and capacity of these ships have increased.

They account for around 21 per cent of the merchant fleet worldwide. There are mini bulk carriers with single holds and humongous ones with many cargo holds.

They are of 6 types based on their carrying capacity-

1. Small bulk carriers with a capacity of 3000 to 23,999 tonnes

2. Handysize with a capacity of 30,000 tonnes

3. Handymax, with a capacity of 37,000 tonnes

4. Panamax, which can load 75,000 tonnes

5. Capesize, which can accommodate 80,000 to 199,000 tonnes

6. Very Large with a capacity of < 180.000 Tonnes

There are also conventional, gearless, geared, and self-discharging bulkers and lakers.

RORO Ships

RORO is an acronym for Roll-on/Roll-off. RORO Ships are cargo ships that accommodate wheeled cargo like trucks, buses, automobiles, railroad cars, etc., driven on and off the vessel on their wheels or via a self-propelled modular transporter. On the other hand, Lift-On/Lift-Off or LOLO ships load and unload cargo through cranes.

RORO Ships are of various types like-

• Pure Car Carrier (PCC) and Pure Car and Truck Carrier (PCTC) RoRo Ships
• Container Vessel + Ro-Ro (ConRo) Ship
• General Cargo + Ro-Ro Ship (GenRo) Ships
• RoPax
• Complete RoRo Ships

Tanker Ships

Also called tank ships, they carry liquids or gases and are categorised according to cargo type and size. Common tanker ships include oil tankers, chemical tankers, product tankers, and gas carriers. There are also inland waterway tankers which operate on canals and rivers.

Tanker ships carry molasses, vegetable oils, wine, crude oil, chemicals, etc.

Different types of tanker ships based on cargo type include-

• Oil Tankers: They carry crude oil and other products.
• Liquefied Gas Carriers ship Liquified Petroleum Gas, Liquified Natural Gas and other gases.
• Chemical & Product Tankers carry hazardous chemicals and liquids.
• There are tankers that carry molasses, fruit juices, wine, alcohol, etc.

Based on their size, tankers are divided into the following categories-

• VLCC
• ULCC
• Panamax
• Aframax
• Suezmax
• Capesize
• Handymax
• Lighters

Offshore vessels

These ships aid in oil and gas exploration and offshore construction activities. They are of different types like-

• Supply ships which cater to rigs and platforms located offshore.
• Crane barges, crane ships or floating cranes are vessels with cranes used to lift heavy loads.
• Pipe-laying ships that lay underwater cables and pipes.
• Semi-submersible platforms are movable offshore drilling rigs.
• Drill ships assist in drilling wells offshore or drill for scientific reasons, such as research.
• Accommodation Barges can function as a hotel or even accommodate goods.
• Production platforms extract, process, or store oil and gas until they reach the shores.
• Floating Storage Unit is a vessel used to store oil and its by-products.
• A floating Production and Storage Unit is a ship employed in the offshore energy sector to produce and process hydrocarbons and store oil.
• Anchor handling vessels are involved in offshore installation and construction.
• Experienced divers, marine biologists, researchers, etc., employ diving ships to dive into the ocean to collect samples and study underwater flora and fauna.

Fishing Vessels

As the name suggests, these vessels are used for commercial, artisanal, or recreational fishing in seas, oceans, lakes, or rivers. There are two kinds: trawlers and non-trawler fishing vessels.

A Trawler is engaged in fishing commercially. It is also called a dragger and employs trawls to catch fish.

This fishing technique is where a trawl is dragged or pulled underwater behind trawlers.

Purse Seiners use a massive net to surround an entire colony of fish.
Factory Ships or fish processing vessels have the equipment to process and freeze fish or other seafood products.

Specialty Vessels

As the name suggests, these are built for specific uses and include-

• Tenders are used to support other ships, usually to transport supplies and people.
• Tugs manoeuvre vessels by towing and pushing them.
• Pilot Crafts transport harbour pilots.
• Cable-laying ships are used to lay cables on the seafloor.
• Research vessels, including polar vessels, seismic vessels, and oceanographic vessels, are used for research.
• Livestock carriers accommodate animals.
• Icebreaker ships operate in cold regions like the Arctic, Antarctic, and North Sea to break through the ice and make way for other vessels.
• Salvage vessels recover goods lost in the vast expanse of seas and oceans.
• Lightships function as lighthouses in deep waters, especially in areas that are not suitable for the construction of a lighthouse.
• Barge carriers are flat-bottomed vessels that operate on rivers and canals and carry heavy goods.
• Lastly, we have timber carriers that transport timber.

Passenger Ships

Passenger ships transport people from one place to another. They are mainly of two types: ferries and cruise ships.

Ferries usually carry passengers and vehicles over short distances. There are cross-channel ferries, coastal ferries and harbour ferries.

On the other hand, cruise ships are massive and built for a luxury sailing experience. They are literally floating hotels with all the amenities and forms of entertainment and relaxation one can possibly imagine.

They can accommodate thousands of people on a single voyage, and due to their popularity, the cruise ship sector has become a major source of employment and income in the maritime industry.

Apart from these two, there are other passenger ships, including pilgrimage vessels, liners, etc.

High-Speed Craft

These are special types of highly modern and high-speed vessels. Though they are not used much commercially, some were deployed and tested on small-scale merchant vessels.

Major types of high-speed crafts include

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

Dredgers

This process is performed under the water, in shallow areas or freshwater environments, to remove excessive sediments, widen a channel, and make it navigable. Dredgers have evacuation equipment to remove sediment, etc, from the seafloor.

Dredgers offer essential, safe bottom clearance for safer voyages, making shipping safer and easier. They are also used in deep-sea mining.

There are three kinds of dredgers: mechanical, hydraulic and others.

Mechanical ones include bucket, grab, backhoe, and bucket ladder dredgers. Hydraulic ones include suction dredgers, trailing suction hopper dredgers, and water injection dredgers.

Others include Air-lift Dredgers, Augur Suction Dredgers, Pneumatic Dredgers, Reclamation Dredgers, Amphibious Dredgers, plough dredgers, bed levellers, and jet-lift dredgers.

Bitumen/Asphalt carriers

These ships are specially designed to carry bitumen goods. Their main characteristic is floating tanks, which can expand at high temperatures.

They are sometimes insulated to prevent heat loss. Their size range is 1000 to 6000 DWT, and they ship oil from offshore petroleum units to refineries.

Reefer Ships

These refrigerated cargo vessels transport perishable cargo like dairy, fruits, vegetables, meat and other miscellaneous products that need temperature control. Cargo Holds of reefer ships are insulated, and cold air is pumped into them to maintain the temperature and prevent heat from entering the area.

However, using refrigerated containers on container ships has largely replaced the requirement for conventional reefer ships.

Reefer ships fall into three categories: side door, refrigerated container, and conventional.

Sailing Ships

Sailing vessels use the power of the wind through sails fixed on masts. They come in many designs, such as square-rigged and fore and aft sails.

Their usage peaked from the 15th to the 19th centuries when advanced shipping technologies had not yet been devised.

They played a vital role in conducting maritime trade and naval wars. All bigger vessels were called ships, and with the coming of steam power, people called these steamships to differentiate them from sailing ships.

Nowadays, sailing ships are used for leisure and tourism purposes. Many rich people have their private sailing ships.

Conclusion

The Merchant Navy has many types of ships that travel vast distances to transport cargo from one port to another. These ships are essential for maritime trade and vital to the global economy.

What merchant ships have you sailed on? Do let us know in the comments!

You might also like to read-

• The Ultimate Guide to Tug Boats: Types, Functions, and Applications
• The Ultimate Guide to Different Types of Boats – Top 20
• What are Offshore Vessels?
• What are Very Large Crude Carrier (VLCC) and Ultra Large Crude Carrier (ULCC)?
• What Are Gas Tanker Ships – Everything You Wanted To Know
• Understanding Livestock Carriers – Design, Construction and Safety

About Author

Zahra is an alumna of Miranda House, University of Delhi. She is an avid writer, possessing immaculate research and editing skills. Author of several academic papers, she has also worked as a freelance writer, producing many technical, creative and marketing pieces. A true aesthete at heart, she loves books a little more than anything else.

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