According to different production methods, it can be divided into hot rolled pipe, cold rolled pipe, cold drawn pipe, extruded pipe, etc.
1. Hot rolled stainless steel seamless pipe is generally produced on automatic pipe rolling unit. The solid tube blank is inspected and removed from surface defects, cut to the required length, centered on the perforated end face of the tube blank, and then sent to a heating furnace for heating and perforation on the perforator machine. In the perforation at the same time continuous rotation and forward, under the action of the roll and the head, the inside of the tube blank gradually forms a cavity, called capillary. It is then sent to an automatic pipe rolling machine for further rolling. Finally, the whole wall thickness of the whole machine is averaged, and the diameter is determined by the sizing machine to meet the specification requirements. The production of hot-rolled seamless steel pipes using continuous pipe rolling mills is a more advanced method.
2. If you want to obtain a smaller size and better quality seamless pipe, you must use cold rolling, cold drawing or a combination of the two. Cold rolling is usually carried out in two-roll mills, where the steel pipe is rolled in an annular hole pattern consisting of a variable-section round hole groove and an immovable conical head. Cold drawing is usually carried out on a single-chain or double-chain cold drawing machine of 0.5~100T.
3. The extrusion method puts the heated tube blank in a closed extrusion cylinder, and the perforated rod moves together with the extrusion rod to extrude the extruded part from the smaller die hole. This method can produce steel pipes with smaller diameters.
Such steel pipes can be divided into stainless steel seamless steel pipe and stainless steel welded steel pipe (seam pipe) two categories, according to the different manufacturing processes can be: hot rolled, extruded, cold drawn and cold rolled these basic types, according to the cross-section shape can be divided into round pipe and special-shaped tube, widely used is round steel pipe, but there are also some square, rectangular, semi-circular, hexagonal, equilateral triangle, octagonal and other special-shaped stainless steel steel pipes.
For the steel pipe under fluid pressure to carry out hydraulic test to test its pressure resistance and quality, under the specified pressure does not leak, wet or expand as qualified, some steel pipes also according to the standard or demand requirements for crimping test, flaring test, flattening test.
Seamless stainless steel pipe, also known as stainless steel seamless pipe, is made of steel ingots or solid tube blanks made of capillaries by perforation, and then made by hot rolling, cold rolling or cold drawing. The specifications of seamless steel pipes are expressed in the number of millimeters of outer diameter * wall thickness
