Cargo ships and their classification

Any domestic classification of ships relies primarily on their purpose. Cargo ships are classified the same way. Civilian are subdivided into fishing, transport, belonging to the technical fleet and auxiliary services.

Transport

These cargo ships are the main core of the river and marine fleet. They are designed to carry a variety of goods. This group has its own internal classification: cargo ships, cargo and passenger and special. Actually, the cargoes are bulk and dry-cargo, and they include ships of various purposes and types.

Each of these types will be considered in detail, including general purpose dry cargo ships and specialized ones carrying strictly defined cargoes. Cargo ships intended for general transport are of general use. They belong to the most common type.

Dry cargo ships

Dry cargo cargo ships are ships with spacious holdings occupying all their main part. They are one-, two- and three-deck, depending on the size of the vessel. In the engine room is most often a diesel unit, it is located either in the stern, or shifted closer to the nose for a couple of cargo holds. For each cargo hold project, cargo ships provide for their own hatch or even not one that closes mechanically.

Cargo means are cranes or individual arrows with a payload of up to ten tons, and heavy vessels are supplied and stronger - up to two hundred tons. Modern marine cargo vessels have refrigerated holds for perishable cargo and diptans for edible liquid oils. But river dry cargo ships, regardless of size and capacity, are equipped with only one cargo hold, so it is more convenient to carry out loading and unloading operations.

Specialized vessels

Such bulk carriers can be divided into groups for refrigerated, trailer, container ships, timber trucks, ships for the transport of automobiles, bulk cargo, livestock and the like. Refrigerators transport perishable products - fruits, fish or meat. In cargo holds - reliable thermal insulation, refrigeration units, providing constant cooling with a temperature of five degrees to minus twenty-five. Modern refrigerators can not only maintain the temperature, but also produce a quick freeze, they belong to the production and transport refrigerators. Dry cargoes intended for fruit transportation are equipped with enhanced ventilation of all holds.

The technical characteristics of cargo ships provide for a load-carrying capacity of up to twelve thousand tons, the speed of such dry-cargo ships is higher than that of general-purpose vessels, since the products are perishable and require the fastest possible delivery. Container carriers transport pre-packed goods in containers weighing from ten to twenty tons each, and the ship itself raises twenty thousand tons and moves at a speed of up to thirty knots. Containers are quickly and easily loaded and unloaded due to the fact that the deck of container ships is adapted to a wider opening above the holds. Most often, loading and unloading is carried out by means of the terminal - portal cranes. Timber trucks are a type of container ships, they are barges, called lighter carriers, they are unloaded from the ship directly to the water and towed to the pier.

Trailers

This type of vessel is today possessed by all naval powers, since this ship is powerful, fast-moving and allows you to promptly perform loading and unloading - about ten times faster than on ships not equipped with special trailers, on which cargoes are simply imported and taken from the ship. Industrial development has significantly expanded and strengthened trade between countries, now it is necessary to transport construction equipment, agricultural and transport equipment for long distances. Sea and river cargo ships perform such tasks as best as possible.

Trailers carry goods in trailers, which are simply rolled into the holds. The load capacity of trailers is from one thousand to ten thousand tons, and the speed is up to twenty six knots. This is the most promising and current type of cargo ship to date. They are constantly being improved. Many trailers, in addition to cargo in the holds, are adapted to carry containers on the upper deck. Such vessels even got their name - piggyback.

Bulk carriers

Bulk cargoes are transported by specialized vessels - bulk carriers. It can be ore and ore concentrates, coal, mineral fertilizers, building materials, grain and the like. More than seventy percent of all dry cargo transported by sea or river routes is exactly bulk cargo, and therefore the number of vehicles is growing very fast: today more than twenty percent of the tonnage of the world fleet belongs to this type.

Bulkers are divided into universal, for heavy cargo and for light. Many ships are adapted for a dual purpose: there is ore, back - oil or cars, or cotton, whatever. This type - single-deck vessels, with superstructure and engine room in the stern. The payload is simply enormous - up to one hundred and fifty thousand tons, but the speed is not high - up to sixteen knots. Cargo is transported in holds with inclined walls for self-distribution of cargo - both longitudinally and transversely. Between the side and the walls there are tanks for water ballast. Sometimes in the holds are made longitudinal bulkheads to reduce roll, if the load is displaced, and the second bottom is designed with reinforcements and thickened flooring for the convenience of cargo operations.

Self-propelled vessels

This type of vessels are divided into tankers for oil products, crude oil, fuel oil, diesel fuel, gasoline, kerosene; On gas carriers; Vessels for transportation of chemicals - molten sulfur, acids and the like; On transports for liquid cargo - water, wine, cement. Tankers are the most common in the world: more than forty per cent of the world tonnage in the transport fleet. This single-decker vessel, superstructure and engine room are at the stern.

The cargo part is divided by bulkheads into compartments called tanks. Some of them serve as water ballast for the return flight. On the nose there is a pump room. Tankers are extremely fire dangerous, therefore they are equipped with powerful fire-fighting systems. Load capacity of them from thousands of tons from distributors to four hundred thousand tons from supertankers - the world's largest vessels. River vessels are also not heavily loaded, some have up to twelve thousand tons. These are also extremely powerful cargo ships. The photo above is a sea tanker, and below is a river tanker.

Gas carriers

These ships carry liquefied gases - methane, propane, butane, ammonia, as well as natural gases, which are valuable raw materials and excellent fuel. Usually gas is either liquefied, or chilled, or under pressure. Gas carriers under the projects are radically different from tankers, since they have embedded cylindrical tanks - horizontal or vertical, spherical or rectangular. Insulation on gas carriers must be very reliable.

Cargo operations are performed using a special system, which includes pumps, compressors, pipelines and an intermediate tank. Ballast in working tanks should not be taken, and therefore it is equipped on the sides or in a double bottom. Transportation of gas is always explosive, so there is a powerful ventilation system and alarms for gas leaks. Extinguishing of fires occurs with the help of carbon dioxide. At present, the class of combined vessels is in demand, which is very beneficial for sea and river transport - empty runs are excluded. Thus, cotton-leaved cotton products, oil-carriers and similar vessels appeared.

РС-300

From 1967 to 1984, seiners of the 388M type project "Freight vessel RS-300" were produced at three shipyards of the USSR. Four hundred eighty-six such seiners were built, among them those that served as fishing, fishing, and mining vessels. In addition, on the basis of this particular project, there were thirty-three research vessels (for example, the famous "Cautionary"). For the purposes of scientific research, about a dozen such vessels have long worked.

When the Soviet Union ceased to exist, the need for them disappeared, some ships became private property, and most of them served and jumped. Those who remained were re-qualified as fishermen. In the Far East, such vessels, in small quantities, until recently, still worked in the border guard service. In private hands fishing RS-300 afloat and now.

Other classification

In addition to the classification by designation, it is possible to subdivide cargo ships on other grounds. This is the principle of maintaining the water, the area of navigation, the type of engine, the principle of motion, the genus of the propulsion, the material and the shape of the hull. The principle of maintenance can be hydrodynamic - underwater wings, air cushion, glider, and also hydrostatic - air cavern, displacement (catamarans).

The principle of movement divides vessels into self-propelled vehicles - with an energy installation, non-self-propelled vehicles - with pushers and tugs, and also rack-mounted - pontoons, landing stages. On the area of navigation it is possible to distinguish sea, mixed (river-sea) and inland navigation (river) ships. The latter are intended for short voyages on inland waterways. The type of the main engine divides the cargo vessels into motor ships (internal combustion engine) and diesel engines (electric motor). In the Navy, also nuclear-powered ships and turbo-boats are used. Vessels are subdivided according to the type of propulsor into wheel, screw, water-jet, with air screws and wings. The type of material of the case can be metal, fiberglass, reinforced concrete, wooden. Also, vessels can be self-propelled and not (barges).

Cargo aircraft

A cargo plane is used to transport not passengers, but a variety of goods and equipment. They are immediately and easily recognized even by an unprofessional look. Wings are located high, the thickness of the hull, fuselage, clearly conspicuous, some "squat" (so that the cargo was closer to the ground for easy loading and unloading). More wheels on the chassis, high tail.

Air freight began in the distant year 1911 - from the post office. Of course, there were no special projects, they appeared only in the twenties. The very first cargo plane was produced in Germany - Air 232. Before that, the cargo was transported with lightly adapted "Junkers". Air liners, built for special projects for cargo transportation, are called freelancers. They are not adapted for passengers.

The largest air carriers of goods

A real flying monster - An-225 ("Mriya") was developed in Antonov Design Bureau in 1984, the first flight was held in 1988. The six-engine turbojet, the two-tailed tail and the swept wing had to create such a load capacity to transport parts of the launch vehicles to the spaceport. The Soviet space program Buran assumed the use of this particular aircraft, which is capable of raising more than two hundred and fifty tons.

Lockheed C-5 Galaxy is an American cargo airliner born in 1968, it is a military transport vehicle capable of simultaneously carrying six armored troop carriers, two tanks, four infantry fighting vehicles, six Apache helicopters. Hughes H-4 Hercules - very powerful rarity of 1947 of creation, the wingspan is ninety eight meters. Now it is a plane museum, because it was made in a single copy. Boeing 747-8I - a passenger and cargo aircraft, released in series production in 2008. He raises four hundred forty-two tons on take-off, but besides the cargo he takes on board almost six hundred passengers.