The manufacturing methods of seamless steel pipe

According to different manufacturing methods,seamless steel pipe can be divided into hot-rolled seamless steel pipe,cold-rolled seamless steel pipe,cold-drawn seamless steel pipe and extruded seamless steel pipe.

What is hot rolled seamless steel pipe?

Hot-rolled seamless pipes are generally produced on automatic tube rolling mills. The solid billet is checked and cleared of surface defects, cut into the required length, centered on the end face of the billet perforation, then sent to the heating furnace for heating, and perforated on the perforator.Under the action of the roll and the top, a cavity is gradually formed inside the billet, which is called capillary. It is then sent to the automatic pipe mill to continue rolling. Finally, the wall thickness of the whole machine is equalized, and the sizing machine is used to calibrate the diameter, which meets the specifications.It is an advanced method to produce hot-rolled seamless steel tube by continuous pipe rolling mill.

ASTM A53 Grade B seamless steel pipes

ASTM A53 Grade B seamless steel pipes

What is cold rolled and cold drawn seamless steel pipe?

If we want to obtain seamless pipes with smaller size and better quality,we must adopt cold rolled,cold drawn or combination of the two methods.Cold rolling is usually carried out on a two-roll mill.Steel pipes are rolled in an annular pass consisting of a circular groove with variable cross-section and a fixed conical head.Cold drawing is usually carried out on single-chain or double-chain cold-drawing machines of 0.5-100T.

Galvanized seamless steel pipes

Galvanized seamless steel pipes

What is extrusion seamless steel pipe?

The extrusion method is to place the heated tube blank in a closed extrusion cylinder,and the perforating rod moves with the extrusion rod to extrude the extruded part from a smaller die hole. This method can produce steel pipes with smaller diameter.

Haihao Group can use all the manufacturing methods to produce seamless steel pipes,we produce the seamless pipes in different standards such as ASTM A106,ASTM A53,ASTM A179,ASTM A192,API 5L,DIN 1629,DIN 2391-1,EN 10208,JIS G3454,G3455,G3456 or as customers’ requirements.The products materials contain carbon steel,stainless steel and alloy steel.If you want to know more about our pipeline products,please email