The production method of seamless steel pipe applied to FPSO ships

The welded steel pipe used in FPSO ships is made of steel plate or strip after being rolled and formed.

The straight welded pipe production process is simple, high production efficiency, low cost, rapid development. The strength of spiral welded pipe is generally higher than that of straight welded pipe. The welded pipe with a larger diameter can be produced with a narrow blank, and the welded pipe with different diameter can also be produced with the same width of blank. However, compared with the same length of straight seam pipe, the weld length increases by 30~100%, and the production speed is lower.

The large diameter or thick welded pipe, generally made of steel blank directly, and small welded pipe thin-wall welded pipe only needs to be directly welded through the steel strip. Then it is simply polished and brushed.

Welding process flow:

Raw material uncoiling -- leveling -- end shearing and welding -- sleeve -- forming -- welding -- internal and external bead removal -- precorrection -- induction heat treatment -- sizing and straightening -- eddy current testing -- cutting -- hydraulic pressure inspection -- pickling -- final inspection (strict control) -- packaging -- shipment.

Hebei Haihao Group can produce various types of seamless pipes including carbon steel, stainless steel and alloy steel pipes for the construction, modification, and maintenance of FPSO ships.