Marine seamless steel pipe types

The seamless steel pipe is very common in marine engineering. Two systems of the ship and marine engineering demand roughly three types of steel pipe:

Steel pipe in the conventional system

Steel pipe in construct

Steel pipe for special purpose

Steel pipe in the conventional system

Different ship and marine engineering, both conventional systems have a dedicated system.

The ship service life of 20 years. Many of the conventional systems, bilge water, ballast, dewater sewage, air, measurement, injection, domestic water, fire, cargo oil stripping, breathable, inert gas, heating, washing, foam extinguishing sprinkler, vapor, liquid level telemetry, valve remote control systems, special ships also include a dedicated system for the transportation of liquefied petroleum gas (LPG), liquefied natural gas (LNG). The marine engineering service life of up to 30 years, or even longer. Marine engineering in addition to the conventional system, special drilling equipment systems, crude oil / LPG / LNG processing workflow system, special mooring system, flare system, and so on. It has been statistics, ship pipe annual consumption of 450 million tons, about 440,000, its standards are GB, YB, CB, 70% of the steel pipe connection. Only a 30-ton very large crude oil pipes for the amount of up to tens of kilometers, only steel pipe usage (including), there are about 1,500 tons, of course, the amount of 40,000 tons relative to the hull structure or limited. In addition, taking into account the same ship, the construction of ships, as well as many other ships, the cumulative dosage is also a lot of. And a 300,000 tons-class number of large FPSO pipe over 30,000, more than 90 km in length, which is the same tonnage level 2 to 3 times. Therefore, the shipbuilding industry has become a big user of the steel pipe market.

Steel pipe in construct

Steel tube marine engineering applications, in addition to the above conventional system with a dedicated system, many constructed a large number of steel pipes, such as jacket, underwater steel piles, Casing, mooring bracket, helicopter platform, torch tower. Type of steel pipe, material specifications, with the same diameter, reducers, different wall thickness, as well as a large number of Y, K, T-managed nodes. Such as jackets, steel piles, wellhead impermeable sleeves, mostly large diameter steel pipe sizes, are generally made of rolled steel. Their material for E36-Z35, D36-Z35, E36, D36. Such steel pipe standards have not with YB, CB, and mainly is GB712-2000. The production of steel pipe structure steel pipe manufacturing practice SY/T10002-2000 was developed by China’s Petroleum Industry Standards and Technology Commission (CPSC). Since China does not have specialized enterprises, is usually the purchase of steel plates from construction units, a self-molding process.

Steel pipe for special purpose

Special purpose steel special steel pipe used in the specific working environment and the working medium. Undersea pipeline is typical specialty steel pipe, the demand for larger, high strength, small tolerances, good corrosion resistance. Currently, pipeline production is only in its infancy, because of the welding materials, corrosion resistance or fewer Specifications (diameter and wall thickness), expensive, etc. China’s offshore crude oil needs insulation transport. In the past, using the double pipe insulation structure, was safe and reliable. But as a protective pipe steel pipe is very economical, and offshore pipe laying ago, has to carry out internal and external pipe welding, greatly reducing the efficiency of the pipe laying, to cause installation costs to increase exponentially. Into the 21st century, it has launched a concrete counterweight steel pipe. Its structure is (from inside to outside): anti-corrosion layer of steel, epoxy powder (FBE), polyurethane insulation, polyethylene (PE) jacket tube, reinforced concrete counterweight layer (the internal configuration of the steel mesh). This type of special steel, China has imported from abroad, such as the Bohai Penglai 19-3 oil field, a project using Malaysian BREDEROPRICE company products. China after research and testing, and in 2002 built-in Tanggu, China’s first concrete with heavy steel pipe production line, has thousands of kilometers of pipelines for offshore oilfield products. It is reported that using this steel per kilometer subsea pipeline to reduce the cost of 50 million to 100 million, and greatly reduce the cost of offshore oilfield development so that a number of marginal oil fields are cost-effective to develop.