First, the method of ship classification
Modern ships serve transportation, port construction, fishery production, scientific research and investigation. With the development of industry and the expansion of shipping services, ships are becoming more and more specialized. Different departments have different requirements for ships, and the navigation area, navigation state, propulsion mode, power plant, shipbuilding materials and uses of ships are also different, so there are many types of ships, which have their own characteristics in ship type, structure, operational performance and equipment.
1. Navigation area of the ship: According to the navigation area, the ship can be divided into three types: ocean-going ship response, harbor ship and inland river ship. Ships sailing on the lake are also generally classified as inland river ships.
2. Navigation state of the ship: According to the navigation state, the ship can be divided into three types: floating, sliding and flying. Floating refers to a ship that floats on the water when its weight and displacement are equal (also called displacement ship). Submarines are also floating. A planing boat means that when sailing at high speed, most of the hull is lifted by the dynamic action of water and glides on the water surface. When the ship is sliding, the displacement is smaller than when it is at rest, at the same time, the wet surface area is reduced, the water resistance is greatly reduced, and the ship speed is accelerated. Such as speedboats and hydrofoils. A ship sailing in the air, its hull is completely out of the water. Such as hovercraft and flapping-wing craft.
3. Propulsion mode: According to the propulsion mode, ships can be divided into primitive human-propelled ships such as tie rods, pulling, rowing and rocking, and sailboats propelled by wind; Mechanically propelled open boats, water jet boats, propeller boats and air-propelled boats. The DC paddle wheel is the oldest propeller, because the ship is driven by machines. Later, a propeller propeller was installed at the lower stern of the ship. Later, for a few ships with special requirements, some added ducts to the stern propeller, and some added auxiliary propellers to the stern. The blades of most ship propellers are fixed, and the propeller with adjustable pitch is used for ships that often need to change working conditions. Ships in shallow waterways are also propelled by water jets. Air propellers are used to propel fully floating hovercraft and aircraft.
4. Power plant: Ships can be divided into steam engine ships and internal combustion engine ships according to the types of power plants. Electric propulsion ship and nuclear power plant ship. The early steam reciprocating machine has been eliminated. Steam turbines (including steam turbines and gas turbines) are used in some high-speed passenger ships and warships. At present, diesel engine power plant is widely used in various ships. Small boats are also driven by gasoline engines. An electric propulsion ship uses an internal combustion engine or a steam engine to drive a generator (or directly uses a storage battery) to generate electricity, and then drives a motor integrated with a propeller to propel the ship. The propeller speed of this power plant can be adjusted at will, and the operation is simple and convenient. Submarine, icebreaker factory, scientific research ship, train ferry and other ships with special requirements are used. Nuclear power plant is an advanced power plant in the world. It uses nuclear reactor to generate steam heat energy through the reaction of nucleus to drive steam turbine to run.
Second, the classification of ships.
Due to the development of ships, there are many kinds of modern ships, which can be classified according to hull materials, such as wooden ships, steel ships, cement ships and FRP ships; According to the navigation area, there are ocean-going ships, near-ocean ships, coastal ships and inland ships; According to power plants, there are steam engines, internal combustion engines, steam turbines, electric power ships and nuclear power ships. According to the propulsion mode, there are open boats, propeller boats, horizontal propeller boats and sail-assisted boats. According to the navigation mode, there are self-propelled ships and non-self-propelled ships; According to the navigation state, there are drainage vessels and non-drainage vessels. The most telling feature of ships is their classification according to their uses, which can be divided into two categories: military and civilian.
(1) Classification of civil ships:
Transport ships-passenger ships, passenger and cargo ships, cargo ships (general cargo ships, bulk carriers, container ships, ro-ro ships, barge ships, oil tankers, liquefied gas carriers, refrigerated ships, etc.). ), ferries, barges, etc.
Engineering ships-dredgers, cranes, floating docks, salvage ships, laying ships (cable laying ships, pipeline laying ships, etc.). ) and piling boats.
Fishing boat-net fishing boat (trawler, purse seine fishing boat, gill net fishing boat, etc.). ), fishing boats, whaling ships, fishery processing ships, fishery survey ships, refrigerated transport ships, etc.
Port ships-icebreakers, pilot ships, fire boats, supply ships, traffic ships, work ships (survey ships, navigation ships, etc.). ), oil slick recovery ship, etc.
Marine development ships-marine survey ships, submersibles (ships), drilling ships, drilling platforms, etc.
Tugboats and pushers-ocean tugboats, harbor tugboats, inland river tugboats, ocean tugboats, inland river tugboats, etc. High-speed boats in the development of navigation AIDS-hydrofoils (paddle hydrofoils, fully immersed hydrofoils), hovercraft (full floating hovercraft, side-wall hovercraft), flapping-wing boats, semi-submersible small surface boats, wave-piercing boats, etc.
(2) Classification of military ships:
Combat vessels on the water-aircraft carriers, helicopter carriers, battleships, cruisers, destroyers, frigates, missile boats, torpedo boats, hunting submarines, escort boats, etc.
Water attack submarines (diesel engine power, motor power) and strategic missile submarines (conventional power, nuclear power) in combat vessels.
Special combat ships-amphibious ships (amphibious command ship, amphibious assault ship, dock landing ship, amphibious dock transport ship, tank landing ship, amphibious cargo ship, vehicle and personnel landing boat, general landing boat), mine-laying ships, minesweepers and mine-hunting boats.
Auxiliary ships-rear support ships (transport ships, fleet supply ships, supply maintenance ships, health service ships, mine fishing boats), maritime rescue ships (offshore rescue ships, ocean rescue ships, submarine rescue ships, icebreakers), intelligence support ships (marine survey ships, reconnaissance ships, communication ships, survey ships), test training ships (missile target ships, missile survey ships, weapon test ships, icebreakers) This kind of ship is the same as civil ships such as exploration ship, piling ship, crane ship, barge, tugboat, dredger, traffic ship, pilot ship, water supply ship, beacon ship, light ship, fire-fighting ship and floating dock.
Civil ships are usually classified according to their uses, as follows:
1. Passenger ship refers to the ship used to transport passengers and their luggage. Passenger ships carrying a small amount of goods are also called passenger and cargo ships. Because most passenger ships sail regularly, they are also called passenger ships. The multi-deck superstructure has good sinking resistance, generally "No.2 cabin is unsinkable", and the ship speed is relatively high, generally 16-20 knots (kn). Passenger > 12 people.
In the International Convention for the Safety of Life at Sea (SOLAS Convention), all ships carrying more than 12 passengers should be regarded as passenger ships. The outline of the passenger ship is shown in the figure. It is characterized by good navigation performance, perfect safety equipment and living facilities, tall superstructure and high ship speed, generally around 20kn (knots/hour). Some short-distance passenger ships use hydrofoils and hovering boats, and the ship speed is generally around 40kn.
2. Dry cargo ships can be divided into:
(1). General cargo ship: Also known as general cargo ship, its characteristic is that the cargo hold is designed with multi-deck structure, generally with 2-3 decks. In order to facilitate loading and unloading, the hatch size of each cargo hold is large, and it is equipped with a derrick (2-5T) or a crane (120T). There are usually 3-6 cargo holds. General cargo ship refers to a ship that sails on a busy freight route in a specific period, mainly carrying sporadic groceries. This kind of ship sails fast and is equipped with enough lifting equipment. In the ship structure, there are multiple decks to divide the cabin into multiple containers to meet the needs of loading different goods.
(2) Bulk carriers are ships specialized in transporting grain, ore, coal, etc. Because bulk cargo is not afraid of pressure, its cargo hold is a single deck, which is convenient for loading and unloading. According to the different structures, it can be divided into the following categories.
Bulk carrier is a ship used to transport unpackaged bulk goods. According to the different types of goods, it can be divided into grain ships, coal ships and ore ships. Most of these ships are single deck, and there are no columns in the cabin, but there are partitions to prevent the cargo in the cabin from being misplaced when running in the wind and waves. Its characteristic is that the hatch coaming is high and large, and the cross section of the cargo hold is prismatic, which can not only reduce the flat cabin work, but also the triangular cabins at the four corners of the cargo hold are ballast cabins, which can adjust the draft and stability height.
Types of bulk carriers
Handy bulk carrier: refers to a bulk carrier with a deadweight of about 20,000-50,000 tons, among which ships exceeding 40,000 tons are also called handy bulk carriers. As we all know, dry bulk cargo is a bulk cargo by sea. These ships with relatively small tonnage have strong adaptability to waterways, canals and ports, moderate tonnage and convenient and flexible operation, so they are called "portable".
Panamax bulk carrier: As the name implies, this type of ship refers to the largest bulk carrier that can pass through the Panama Canal under full load, that is, it mainly meets the relevant regulations on canal navigation, with a total length of no more than 274.32 meters and a width of no more than 32.30 meters. According to the needs, adjust the scale, type and structure of the ship and change the load capacity. The carrying capacity of this ship is generally between 60,000 and 75,000 tons.
Cape bulk carrier: refers to a bulk carrier with a deadweight tonnage of about 6.5438+0.5 million tons, mainly transporting iron ore. Due to the limited area, it is impossible to pass through Panama Canal and Suez Canal, and it is necessary to bypass Cape of Good Hope and Cape of Horn, which is called "Cape" in Taiwan Province Province. In recent years, the Suez Canal authorities have relaxed the draft restrictions for ships passing through the canal, so most of these ships can pass through the canal with full loads.
Lake bulk carrier: refers to a bulk carrier sailing in the Great Lakes region at the junction of the United States and Canada via the St. Lawrence waterway, mainly carrying coal, iron ore and grain. This type of ship should meet the navigation requirements of saint lawrence seaway in terms of scale. The total length of the ship shall not exceed 222.50 meters, the width of the ship shall not exceed 23. 16 meters, any part of the bridge building shall not extend out of the ship, and the draft shall not exceed the maximum allowable draft of the main waters. The height of the top of the mast from the water surface shall not exceed 35.66 meters. This kind of ship is generally about 30,000 tons, and most of them are equipped with loading and unloading equipment.
3. The ore carrier occupies a small cabin capacity because of its heavy ore ratio and low center of gravity. Therefore, in order to improve the height of the center of gravity, its double bottom is particularly high, and the ballast tanks on both sides of the cargo hold are also very large.
Mineral oil carrier
4. Container ship refers to the ship that mainly carries container goods. The cargo holds are mostly single deck and double hull, which can stack 3-9 layers of containers. Economic speed 19-24kn, container specifications are 40 feet (40×8×8 feet) and 20 feet (20×8×8 feet).
Load the goods into the container in advance, and then load the container onto the ship. The advantages of this mode of transportation are high loading and unloading efficiency, reduced labor intensity, reduced cargo damage and cargo difference, and convenient multimodal transport. At present, container transportation has developed rapidly and has become the main mode of grocery transportation.
Container ships can basically be divided into two categories: full container ships and semi-container ships. The cargo hold and deck of a full container ship can carry containers. Grille frames are installed in the cargo hold to facilitate the fixing of containers. Its deck and cargo cover are flat, and it can hold 2~4 layers of containers. Usually, there is no loading equipment on board, but special equipment on the dock is used for loading and unloading. On the other hand, semi-container ships load containers in some cargo holds, while others load groceries or bulk goods.
The cargo hold of a container ship is very large. In order to ensure the strength of the hull, a double hull is adopted. Not only the loading and unloading efficiency is high, but also the ship speed is fast, mostly above 20k n. At present, the sixth generation container ship has been built, which can carry 8000 containers. Container ships can be divided into three types: partial container ships, full container ships and refitted container ships:
(1). Some container ships. Only the middle of the ship is used as a special space for containers, and other spaces are still full of ordinary groceries.
(2) Full container ships. Refers to the ship specially used to transport containers. It is different from ordinary cargo ships. Its cargo hold is equipped with a grid frame and a vertical guide rail, which is convenient for the container to be put down along the guide rail, and the four corners are limited by grids to prevent dumping. Container ships can stack three to nine containers in the cabin and three to four on the deck.
(3) Convertible container ships. The structure of the cargo container is detachable. Therefore, it can ship containers and general groceries when necessary.
The speed of container ships is very high, and most of them have no lifting equipment, so they need to rely on the lifting equipment on the dock for loading and unloading. This kind of container ship is also called unloading ship.
5. Ro-ro ship, also known as Ro-ro/Ro ship: when the ship is loading and unloading at the dock, the springboard is put down from the stern to the shore, and the container is dragged into the cabin by the trailer. Therefore, it has a special structure, the upper deck is flat, there are no side arcs and beam arches, there are no cargo lifting equipment, there are many decks (2-4 floors), there are few columns in the cargo hold, and the deck is vertical. High cost. The speed is 16- 18kn.
It mainly carries cars and containers. The ship itself does not need loading and unloading equipment. During loading and unloading, springboard is placed on the dock at the stern, side or head of the ship, and cars or containers (mounted on trailers) directly enter and exit the cabin. Realize the loading and unloading of goods. Ro-ro ships are also called getting on or off the ship.
The superstructure of the ro-ro ship is tall, the top open deck is flat, and there is no loading equipment. There are several longitudinal decks in the cargo hold, and cars or trailers can enter each deck through ramps or lifting platforms. Ro-ro has low requirements for the wharf, high loading and unloading efficiency and fast ship speed. However, the cabin capacity utilization rate is low and the cost is high. The advantage of this kind of ship is that it does not depend on the loading and unloading equipment on the dock, and the loading and unloading speed is fast, which can accelerate the ship turnover.
6. Wood transport ship Wood transport ship is a ship specially used for loading wood or logs. This kind of cabin has a large mouth, and there are no equipment such as beams and columns that hinder loading and unloading. Cabin and deck can be loaded with wood. In order to prevent the timber on the deck from being washed overboard by waves, bulwarks of not less than one meter are generally set on both sides of the ship's side. Its cargo hold is required to be long and large, and there are no columns in it.
7. Barge carriers, also known as mother ships, first load the goods on small barges with the same specifications, and then load these small barges on the mother ship for transportation. In other words, a ship carries the big ship on the barge and the goods in the barge.
The advantages of barge transportation are that it can improve the loading and unloading efficiency, shorten the time for ships to dock at the port, speed up the turnover of ships, and is not limited by ports, docks and loading and unloading equipment, and is convenient for organic combination with Haihe River intermodal transportation. The disadvantage is that the high-level organization and management in barge transportation is complex and its development is slow at present. The main advantages of barge carrier are that it is not limited by the depth of the port, does not need to occupy the dock berth, and the cargo is loaded and unloaded at the anchorage, so the loading and unloading efficiency is high. At present, there are two commonly used barge transportation tools, namely "barge on board" and "Haibei".
8. The refrigerated ship is a special ship for transporting perishable goods, such as meat, fish, vegetables and fruits. Its hull structure is similar to that of a general cargo ship, but the cargo hold is small, with good heat insulation function and high-energy refrigeration device. Due to the limitation of supply batches, the tonnage of refrigerated ships is generally below 1 10,000 tons. At present, refrigerated containers used to transport refrigerated goods are developing rapidly. Because of the convenient transportation, it replaces the transportation of refrigerated ships to some extent. The ship is equipped with a refrigeration system, which can adjust various temperatures to meet the needs of different temperatures of goods in each cabin. The cargo hatch is small, the tonnage is not large, and the cargo deck has many floors, usually 8-4 floors.
9. Oil tanker (oil tanker) is a kind of ship mainly used for transporting liquid goods. Oil tankers can be divided into oil tankers and liquefied natural gas carriers according to the types of goods they carry. ) refers to ships carrying petroleum and petroleum products (diesel, gasoline, heavy oil, etc.). ) In order to prevent fire and explosion, live towing equipment is not allowed on the deck, and a steam engine is usually used. There is no double stern structure, so the freeboard is very small, the ship type is full, and the ship speed is not high. 13- 17kn.
The characteristic of oil tanker is that the engine room is located at the stern, and the hull is divided into several oil storage tanks, and the tubing runs through each oil storage tank. Most oil tanks have longitudinal structures and longitudinal bulkheads, which can keep the stability of the ship when it is not fully loaded with goods. In order to obtain greater economic benefits, the deadweight tonnage of oil tankers has been increasing since World War II. At present, the deadweight tonnage of the largest oil tanker in the world has reached more than 600,000 tons.
Tankers mainly carry bulk crude oil. At present, the largest oil tanker in the world can carry 550,000 tons of crude oil. Traditionally, oil tankers with a deadweight of more than 200,000 tons and less than 300,000 tons are called VLCC-supertanker, and those with a deadweight of more than 300,000 tons are called ultra supertanker. Generally, the loading and unloading of oil tankers is completed through a pipeline system with pumps.
10. liquid cargo ship
Liquefied natural gas carrier (LNG carrier for short): LNG is mainly methane, which can only be liquefied if it is frozen at very low temperature (-165℃) and normal pressure. The volume after liquefaction is only 1/600, which is convenient for transportation. The tank has a strict thermal insulation structure, and its shape is stadium-shaped and rectangular.
Liquefied petroleum gas carrier (LPG carrier for short): LPG carriers are divided into fully pressurized LPG carriers; There are three types of fully frozen LPG carriers and semi-pressurized semi-frozen LPG carriers.
Liquid chemical tanker: most liquid chemicals are toxic, flammable and corrosive, and there are many kinds. Therefore, most ships have double bottoms and many cargo holds.
1 1. There are many kinds of engineering ships, which are classified according to their uses: dredging ships; Ship for hydraulic construction; Ships used for marine development; Ships used for danger prevention and rescue; Pipe laying ship, etc.
12. Work boat: refers to the special-purpose ship that provides services or professional work for sailing ships, mainly including: auxiliary boat: tugboat (top) and tugboat, with high strength, good stability and buoyancy, but small hull. Tugboats are characterized by small size, high power, high strength, good stability and flexible operation, and are mainly used to assist other ships in harbor maneuvering. High-power tugboats can also be used for towing at sea.
13. Technical boats include dredgers, cranes, salvage boats, salvage boats, icebreakers and cable laying boats.
14. Dredger is an engineering ship used to dredge navigation channels, deepen berths or dig canals. According to the different dredging equipment, it can be divided into several types, such as rake suction, cutter suction, grab bucket and chain bucket.
15. Floating crane is a special kind of engineering ship, also called floating crane. Most of them are non-self-propelled and towed by tugboats. The lifting weight of a floating crane ranges from tens of tons to hundreds of tons. The lifting capacity of large floating cranes can reach thousands of tons.
16. The salvage ship is a special engineering ship for salvaging sunken ships or underwater abandoned objects. The salvage ship is equipped with cranes, winches and air compressors, as well as diving, electric welding, cutting, repairing and underwater positioning systems.
17. The icebreaker is a working ship specially used to break the ice on the waterway and rescue stranded ships. The bow is tilted forward and specially reinforced. Large-capacity ballast tanks are arranged at the port and starboard of the bow and stern. When breaking the ice, the bow is washed up on the ice, and then the tail ballast water hits the first ballast tank, and the ice is crushed by gravity or the hull shaking from side to side.
18. The cable ship is a special ship for laying submarine cables. It can also be used as a cable maintenance ship. Its bow has a special shape and is equipped with several large-diameter guide pulleys.
19. service boat
A motorboat is a small boat, which is used to pick up and drop off crew and staff.
Supply ship refers to a special ship used to supply fresh water (water ship), fuel oil (oil tanker) and materials to port transport ships.
Pilot ship is a ship specially used to take pilots aboard for pilotage. The hull is painted with obvious colors and marked with pilot marks.
20. The icebreaker has a solid structure and high power.
2 1. Provide safe ships
The rescue ship is a working ship that specializes in rescuing ships in distress. Its shape is similar to that of a large tugboat, its hull is generally white, its speed is fast, and it is equipped with various rescue equipment.
Fireboat is a kind of working boat, which is specially used to put out the fire of ships in the port or buildings near the dock. The ship is equipped with a number of fire monitors to spray foam or high-pressure water columns, and some have lifting platforms to put out high-altitude fires.
22. The scientific research ship is used for marine hydrology, meteorology, geology and biology. This kind of boat. This kind of ship has good navigation, perfect cabin living facilities and strong endurance.
23.fishing boats
Trawler: it can be divided into single towing and double towing; Bottom drag and middle drag; Sea towing and ocean towing; Side towing and stern towing, etc.
Purse seine fishing boats: purse seine fishing boats can be divided into single boat and double boat purse seine fishing boats.
Drift: Also called gill net.
Long-line fishing boat: Long-line fishing is made up of several kilometers of dry rope and many hooked support ropes.
Pole fishing boat: It can be divided into offshore (40- 100 gross tonnage) and offshore (200-500 gross tonnage) fishing boats.
Whaler: Good stability and high speed, generally not less than 16kn.
24. Special ships
The weight of the planing boat is mainly supported by the traction generated during planing.
There are hydrofoils in the front and back of the hydrofoil boat bottom. With the increase of speed, the hydrofoil generates lift and lifts the ship out of the water.
Hover craft, a kind of ship, cushions the hull off the water surface through the air cushion formed by the air pressure of the fan to reduce the water resistance.