Types of cargo ships

Words and Terms to be Remembered

dry cargo ship tanker universal ship general cargo design bulker timber-carrier reefer perishables catwalk pump

pipeline liquefy Ro-Ro vessel vehicle rolling stock trailer ramp container guide lighter LASH quay

Read the text and find the answers to the following questions.

1. What two main groups are all cargo ships divided into?
2. What is the difference between universal and specialized cargo ships?
3. How can dry cargo vessels be classified in dependence of the cargo handling methods they use?
4. What idea do LASH and container ships have in common?

TYPES OF CARGO SHIPS

Cargo ships are the largest group of transport ships. On the one hand, all cargo ships are divided into two types - dry cargo ships and tankers. On the other hand, cargo ships may be divided into universal ships designed to carry general cargoes and specialized ships designed to carry one definite type of cargo. Such specialized ships as bulkers, timber carriers, reefer ships, tankers have long been known.

Bulkers (or bulk carriers) are intended for the carriage of grain, ore, sugar, coal, cement and other bulk cargoes. They are single-decked ships of large size.

Reefer ships are designed to carry vegetables and fruits, cooled and refrigerated cargoes, that's why they are fitted with the refrigeration plant which can keep as low temperature as -18 °C, -30 °C for a long period. Reefers have higher speed to deliver perishables in time.

Timber carriers carry timber in logs. Their main cargo handling equipment is heavy cranes, derricks and loaders. Some of the timber is carried on deck.

Tanker is designed to carry oil and oil products of several grades simultaneously. It is one-deck vessel mostly with aft location of the engine room and bridge superstructure. The cargo spaces are tanks, all tankers being provided with pipelines and pumps. Nowadays there are mammoth tankers of 300,000 dwt (VLCC - very large crude carrier) and up to 800,000 dwt (ULCC - ultra-large crude carrier). There are gas carriers for the carriage of liquefied natural gases (LNG) and liquefied petroleum gases (LPG).

Three main trends in specialized ships have emerged.

One is cargo ships with cargo handling equipment on board. These ships are also called special purpose ships.

The second trend is Roll-on/Roll-off ships (Ro-Ro). They are specially designed for transportation of various wheeled vehicles (cars, rolling stock, tracked vehicles, trailers), as well as unitized, lengthy/bulky cargo units. The cargo handling operations on the Ro-Ro ships are performed in horizontal direction - by driving on/driving off through different kinds of ramps.

The third trend is a container ship. She is intended for the carriage of goods in containers - special boxes of international standards - and provided with the cellular guides in the holds. TEU (Twenty-foot Equivalent Unit) is 6.1 m container for determining ship's container capacity. One of the features of the container ships is large hatches or large deck opening for intensification of cargo operations.

The use of containers for cargoes has encouraged the design of LASH (Lighter-Aboard Ship) or barge carrying ships in which the container is a 60 foot steel lighter. The benefit of a barge carrying ship is that she can load and unload barges in estuaries away from quays. There are two designs of a barge carrying ship - LASH and Sea Bee, which differ in the method of handling barges and in their internal arrangements.

There are also specialized ships to carry different types of cargo such as OBO ship (oil/bulk/ore carrier), PROBO ship (product/oil/bulk/ore carrier), etc. These are called combined ships or combination carriers.

Exercises and assignments

Дата добавления: 2015-11-14