How to Handle the Seamless Steel Pipe Fracture

Domestic high-precision seamless steel pipe generally by increasing the metal alloy in a way to improve the performance of the material, seamless steel pipe after the cold drawing are required to stress annealing, to eliminate the residual stress of the material, improve the organization of materials, improve material plastic, so as to achieve the purpose of preventing the occurrence of fracture failure of seamless steel pipe.

At present, China's stainless steel seamless steel tube are made of ordinary 45 # or 20 # steel 27SiMn steel, cold drawn by the deformation of the metal strength is improved; however, it is at the expense of metal plasticity and toughness for the price. Precision cold drawn seamless steel tubes is its high dimensional accuracy and high strength properties and based on the market, it must ensure that the amount of deformation within a certain range, in order to maximize the performance of the material, reducing the material Negative Effects.

Seamless steel pipe deformation is too small to reach the surface finish and dimensional accuracy requirements, can not meet the strength index member; deformation is too large, seamless steel ductility, toughness is reduced too much, and the grain was pulled excessively elongated to form a fibrous tissue, the metal would have a significant anisotropy. Cold drawn seamless steel tube axially elongated parallel to the direction of the grain, increased strength; radial drawing seamless steel tubes perpendicular to the elongated direction of the grain, but lower intensity, while the largest hydraulic stress it is present in the radial direction of the seamless steel pipe, so that the deformation is too large to give full play to the negative performance of cold-drawn tubes.