Requirements for steel pipe in offshore oil and gas exploitation

The transport temperature of liquefied natural gas must be maintained at -163 °C, which requires the use of steel tubes with stable physical and mechanical properties at low temperatures.

The seamless steel tubes used in the legs of offshore platforms are subjected to the impact of alternating loads from the waves. Therefore, high-grade (X100/X100Q) large-diameter, large-walled steel tubes with large deformation resistance and fatigue resistance are required.

Submarine oil and gas transmission steel pipes are subjected to high pressure in deep water (3000 meters deep, for example). Plastic deformation easily occurs during laying, and the steel pipes are susceptible to corrosion. This requires pipeline steel to resist collapse, fatigue and corrosion.

Taken together, offshore oil and gas pipelines are developing towards low-carbon helium microalloyed and bimetallic composite pipes. Submarine oil and gas pipelines mainly use high-frequency straight-seam welded pipes and submerged-straight-straight-end welded pipes.