According to different production methods,the seamless steel pipe applied in FPSO(Floating Production Storage and Offloading) can be divided into hot rolled pipe, cold rolled pipe, cold drawn pipe and extruded pipe. Here is the production methods of seamless steel pipes:

Hot rolling seamless tube is generally produced on the automatic tube rolling unit.The solid tube billet is inspected and cleared of surface defects, cut to the required length, centralize the perforated end face of the tube billet, and then sent to the heating furnace for heating and perforating on the puncher.Under the action of the roller and the top, a cavity is formed inside the billet, which is called capillary tube. Send to the automatic rolling mill to continue rolling. Finally, the whole machine through the whole wall thickness, through the sizing machine diameter, to meet the specifications. It is an advanced method to produce hot – rolled seamless steel tube by continuous tube mill.

API 5L PSL1 Grade B seamless steel pipes

To obtain smaller size and better quality seamless tube, cold rolling, cold drawing or both methods must be used.Cold rolling is usually carried out on a two-high rolling mill. The steel tube is rolled in a circular groove with variable section and a fixed conical head.Cold drawing is usually carried out on 0.5 ~ 100T single chain or double chain cold drawing machines.

The extrusion method puts the heated tube billet in an airtight extrusion cylinder, and the perforating rod moves with the extrusion rod to extrude the extrusion part from the smaller die hole.This method can produce smaller diameter steel pipe.

Hebei Haihao Group can produce seamless steel pipes in different dimensions, specifications, standards, materials,and which can be used for the construction, modification and maintenance of FPSO ships.If you want to know more about our seamless steel pipes,please email us:sales@haihaogroup.com