Breaking down the most common types of commercial vessels

Enterprise Explains: The different types of commercial vessels. Some 90% of global trade is carried by ships, which is among the most cost-effective methods of transport available globally, according to the Organization for Economic Cooperation and Development. Literally carrying the global shipping industry are several types of vessels that ply the ocean’s waters — each categorized by their respective sizes, volumes, and ultimately what they carry.

In the world of commercial vessels, there are fivecategories: Vessels carrying dry cargo, liquid cargo, general cargo vessels, containers, and specialty vessels. The type of vessel employed by shipping companies will depend on the size and nature of the cargo, their trade routes, and the ports they’ll have to pass through.

DRY CARGO + CONTAINERS- One of the most common cargo vessels that transport cargo are dry cargo vessels, which carry all types of goods, excluding liquids. These vessels are different in size, but are all able to carry large quantities of cargo.

The location is in the name: Most of these vessels are named after the travel routes that they usually take, which include the Panama Canal, Egypt’s Suez Canal, and South Africa’s Cape of Good Hope or Chile’s Cape Horn.

Panamax vessels, for example, are built to pass through the Panama Canal, which means they must be no more than 32 meters wide and 294 meters long, with a draft of 12 meters, according to the American Association of Port Authorities (AAPA) (pdf). These vessels usually have a cargo capacity of some 5k TEUs — or a twenty-foot equivalent unit, and can come in the form of a tanker, a container vessel and a dry bulk carrier. They have a range of 50k-80k deadweight tons (DWTs), which indicates how much weight capacity a ship can carry, according to the AAPA. These vessels usually transport cargo including iron ore, different forms of coal and grains.

Given the constrained infrastructure of the canal, itunderwent a USD 5.2 bn expansion in 2016 in order to accommodate increased demand of container ships that were oversized for its infrastructure. This resulted in the development of the New Panamax vessel. The reconfigured vessel model can carry more cargo — around 13k TEUs.

Suezmax vesselsare the largest vessels that can go through the Suez canal, with a capacity of 120k-200k DWT, with their beam being up to 50 meters at 20.1 m draft, and a length of 275 meters, as per the Suez Canal requirements.

Capesize vessels cannot pass through the Suez or Panama canal due to their larger sizeand ability to haul a capacity ranging between 150k-400k DWT. They are classified as bulk cargo carrier ships as opposed to tanker vessels, and they usually transport raw materials including ores, coal, and minerals. They are the largest dry bulk carrier, and are mainly used to carry large volumes of commodities.

The smallest dry bulk carriers are known as Handymax vessels, and have a carrying capacity of up to 60k DWT. These vessels are dubbed the workhorses of the dry bulk market with a length of some 150-200 m. Handymax vessels are commonly built in Asian shipyards and carry cargo that ranges from cement, steel, and lumber to ores. The advantage of this vessel is that they can carry any form of dry bulk cargo while being able to unload at smaller ports and docks, according to Marine Insight.

For not so dry cargo, there’s reefers. Reefer vessels are refrigerated in order to transport perishable cargo — which includes everything that requires temperature controlled handling including foods such as meat, dairy products, vegetables, fruits, flowers, and pharma products. Shipping companies involved in cold chain supply for reefers usually provide end-to-end integrated solutions as well as cold storage facilities too, such as leading Danish shipping company Maersk. Reefers have a range of temperature variations, with the average for most ranging from -30°C to 30°C, according to Maersk.

LIQUID CARGO- Vessels that carry liquid cargo include crude carriers and liquified gas carriers which can transport either liquified natural gas (LNG) or liquified petroleum LPG. Crude carriers include Very Large Crude Carriers (VLCC) and Ultra Large Crude Carriers (ULCC), which both transport large quantities of crude oil from production fields to refineries. VLCCs have a 250k dwt, white ULCCs have 250k-500k dwt, according to Marine Insight.

Liquified gas carriers are operationally flexible, able to carry both LPG and LNG. What differentiates them from the dry bulk carriers is that these vessels can be quickly emptied and refilled, making it efficient to load and discharge the liquids, according to Transworld Group. LPG vessels carrying propane and butane transport them in a pressurized liquid form, according to Marine Insight., while LNG is cooled and transported as liquid methane.

Aframax vessels are also oil tankers that get their name from the average freight rate assessment (AFRA) system, which was developed due to size constraints that were imposed on large oil tankers entering sea-routes with traffic. These vessels usually weigh around 120k DWT — and most commonly ply the Black Sea, Mediterranean Sea, Caribbean, and North Sea, according to Marine Insight. These tankers can also be used as cargo containers.

SPECIALIZED VESSELS- Specialized vessels are constructed and used for specific purposes: The most commonly used specialized vessels are known as tugboats, which are used to maneuver other vessels around by pulling or pushing them through direct contact or a tow line, Marine Insight explains. Although they are smaller in size, they can be used to dislodge vessels that get stuck due to running aground in narrow water channels.

If you’re wondering how important specialized vessels are to the world, it was two high-powered tug boats that came to the rescue when a large vessel — Ever Given — was stranded in the Suez Canal in 2021, blocking an essential trade artery for a week.

Roll-on/Roll-off vessels — or RoRo vessels— come in various forms and are built to transport wheeled cargo, according to maritime data solution provider Sinay. They are equipped with a special inclined ramp located at either the stern or bow to facilitate the loading and unloading of vehicles, and usually have a capacity of around 4-5k CEU (car equivalent unit), with some able to carry up to 8k vehicles. There are two types of RoRo vessels: Ones that carry just cars, and others that can carry other types of vehicles.