Rolling design of seamless steel pipe

　　Seamless steel pipe can be used to produce high quality oil and gas in harsh environment with high durability requirements. According to the section shape of seamless steel pipe manufacturers, seamless steel pipe can be divided into round and special-shaped, and special-shaped pipe has many complex shapes, such as square, oval, triangle, hexagon, melon seed, star and winged pipe. The diameter is 650mm and the small diameter is 0.3mm. Seamless steel pipe is made of a whole piece of metal and has no seam on the surface, which is called seamless steel pipe. According to the production method, seamless steel pipe is divided into hot rolled pipe, cold rolled pipe, cold drawn pipe, extruded pipe, pipe jacking, etc.

　　In recent years, there has been a trend of oil depletion. Deep and shallow wells are considered clean energy. Unlike ordinary gas and oil development, materials used in deep underground must be able to withstand the harsh environment. Under this condition, the steel pipe can bear more high temperature and high pressure environment, at the same time, it must increase the rate as much as possible to reduce the impact on the environment.

　　It is necessary to design and manufacture steel pipe. Precision seamless steel pipe is made of carbon bonded steel such as 10, 20, 30, 35 and 45, low alloy structural steel such as 16Mn and 5mnv, or composite steel such as 40Cr, 30CrMnSi, 45Mn2 and 40MnB by hot rolling or cold rolling. Numerical simulation technology greatly promotes the development of manufacturing technology.

　　Seamless steel pipe is produced on automatic pipe rolling mill. The surface defects of the solid billet are inspected and cut into the required length, centered on the perforated end face of the billet, then sent to the heating furnace for heating, and perforated on the perforator. Under the action of roller and top, the inner cavity of billet is formed gradually. It is then fed into the automatic pipe mill and continues rolling. The whole wall thickness and diameter of the whole machine are fixed by the sizing machine to meet the specification requirements. It is an advanced method to produce seamless steel pipe by continuous rolling mill. In order to obtain seamless steel pipe with small size and good quality, cold rolling, cold drawing or combination of the two methods must be adopted. Cold rolling is usually carried out on a two high mill. The steel pipe is rolled by an annular groove with variable cross section and a fixed conical head. Cold drawing is usually carried out on 0.5-100t single chain or double chain cold drawing machine.