Bends are widely used in ocean engineering. There are about three types of bends in ship and ocean engineering systems: those used in conventional systems, those used in construction and those for special purposes.
Bends in conventional system
Different ship and ocean engineering have both conventional system and special system.
The service life of a ship is generally 20 years. There are many conventional systems, including bilge water, ballast, drainage, domestic sewage, air, measurement, injection, domestic water, fire fighting, cargo oil, cleaning tank, breathable, inert gas, heating, tank washing, foam extinguishing, sprinkling, evaporating gas, Liquid level telemetry, valve remote control and other systems, special ships also include transportation of liquefied petroleum gas (LPG), liquefied natural gas (LNG) and other special systems. Ocean engineering has a life span of 30 years or more. In addition to conventional systems in marine engineering, there are special drilling and production equipment systems, crude oil / liquefied petroleum gas / liquefied natural gas treatment processes Systems, special mooring systems, torch systems, etc.
According to some statistics, the annual consumption of ship pipes is 4.5 million tons, about 440000. The standard is that 70% of the GB,YB,CB, pipes are connected with each other. Only a 300,000-ton oil tanker can use several tens of kilometers of tubing, and only about 1500 tons of bends, compared with 40,000 tons of ship structure, of course, is still limited. In addition, considering the same kind of ship, to build a number of ships, there are many other ships, so the cumulative consumption is a lot. And a 300,000-ton super large FPSO pipe has more than 30, 000 pipes and a length of more than 90 kilometers, which is the same tonnage class. The other two times. Therefore, the shipbuilding industry has also become a large user of the pipe bend market.
Bending pipe in construction
In addition to the conventional and special systems mentioned above, bends are widely used in many structures, such as jacket, underwater steel pile, waterproof casing, mooring support, helicopter platform, torch tower and so on. This kind of bend pipe has many specifications, high material, same diameter, different wall thickness, and a large number of YKT type pipe joints. Such as jacket, steel pile, wellhead water-proof sleeve, mostly large-diameter size bends, are generally made of steel plate. They are made of E36-Z35CU D36-Z35-E36D36. The standard for this type of bend is no longer YB,CB, but mainly GB712-2000. The manufacture of bend pipe is according to (CPSC) of China petroleum industry standard technical committee "structural bend pipe manufacture specification" SY/T10002-2000. Because our country does not have the specialized enterprise, so is usually by the construction unit to purchase the steel plate after processing molding.
Special purpose bends
Special purpose bends refer to special bends used in specific working environments and working media.Submarine oil pipeline is a typical special bend pipe, which has the characteristics of large demand, high strength, small tolerance, good corrosion resistance and so on. At present, the production of submarine oil pipelines in China is still in the initial stage, because of welding materials, less corrosion resistance or specifications (pipe diameter and wall thickness), expensive price and so on.
China's shipbuilding industry occupies an extremely important position in the development of national economy. It has been studied that out of 116 industries, shipbuilding products involve 97 industries, accounting for 87 industries. Such as metallurgy, materials, machinery, microelectronics, electrical, chemical, hardware, textile, decoration and so on, driving the development of thousands of enterprises. According to relevant data, the shipbuilding industry for each construction of 1 deadweight ton, can solve the upstream 3000 jobs. Shipbuilding industry has condensed people's wisdom and hard work, is the symbol of national comprehensive national strength. In particular, the independent development of large ships and new types of ocean engineering is a measure of whether a country can be included in The standards of the world's largest maritime power.