Types of Commercial Vessels by Type of Cargo and Dimensions
Commercial vessels can be generally divided into wet and dry cargo ships and vary in dimensions /width and length/. Draft or water depth is a limitation that determines the minimum water depth a boat or cargo ship can navigate. Beam or a vessel’s widest point determines the canal locks a commercial ship can fit. Based on size, dry cargo ships can be sub-divided into handymax, handy size, seawaymax, small handy size, etc. Example of wet cargo ships are ULCC, VLCC, and Q-Max. In addition, ships also fall in several major categories based on type of cargo, including reefer, multi-purpose, dry bulk, tanker, and container ships. Below are some common categories based on type of cargo and maximum dimensions.
These are specialized commercial ships that are used to move liquid cargo. Based on the type of cargo they move, tankers can be divided into product and chemical carriers, liquified gas carriers, and petroleum tankers. Petroleum or oil tankers ship crude oil as well as by-products. There are also vessels for specialized transportation which are used for economic and military needs, including floating storage units, ore-bulk-oil carriers, and replenishment ships.
Product and chemical carriers mainly ship liquid products and chemicals and are further subdivided into integrated tug barges and wine and juice tankers. The third variety, liquified gas carriers ship chemical gases such as liquified petroleum and natural gas. Based on maximum dimensions, tanker ships can be handy, lighters, handymax, panamax, ULCC, and VLCC.
Bulk carrier ships are designed to move cargo such as coals, grains, ores, cooking oils, and refrigerated goods. Other types of bulk cargo include:
- Animal products and livestock, including livestock feed
- Raw products and produce, including corn, rice, seeds, and refined and raw sugar
- Agricultural products such as plastic granules, resin powder, pallets, and fertilizers
- Cements and minerals such as salt, limestone, copper, gravel, and sand
There are also subtypes such as lakers, self-discharging bulkers, BIBO, and conventional bulkers. Based on maximum dimensions, bulk carriers can be seawaymax /passing through the St. Lawrence Seaway/, Newcastlemax /ships that can enter the Newcastle Port, Australia/, and so on.
Container ships are designed to move large quantities of goods in containers. Based on size, such ships are Post-Panamax, Suezmax, Panamax, and Post-Suezmax. Refrigerated container ships are specialized vessels and a sub-category for refrigerated transport. They carry cargo such as offal, fish, cheese and butter, packed meat, and meat carcass.
These commercial vessels are specially designed to move wheeled cargo such as railroad cars, cars, trailers, semi-trailer trucks, and buses. The main categories here are complete RoRo, RoPax, RoRo + container vessel, pure car and truck carrier, and pure car carriers. There are specialized ships such as LMSR which are used to move military cargo. ConRo is another variety that is used to ship vehicles, oversized cargo, and containers, as well as heavy equipment.