Straight seam steel pipe
fracture, hydraulic (pneumatic) parts in the design of the use of mechanical properties, brittle fracture is also related to the use of components temperature.
It has been found that when the temperature is below a certain temperature, it is found that the information will be transformed into a brittle state, and its impact absorption is significantly reduced. This phenomenon is called low stress brittle fracture in cold brittle and high strength metallic materials. In the process, the data organization is far from uniform, isotropic, there will be cracks, there will be inclusions, pores and other defects, these defects can be seen as micro-cracks in the material. Therefore, the design should also be based on the work of the component temperature to select the appropriate cold brittle transition temperature of the information.
In general, it is assumed that the information is uniform and continuous isotropic, according to this method analysis is considered safe design, and sometimes accidental fracture accident. As the hot-rolled tube billet cracks or other defects or high-precision cold-drawn tube was made after the cylinder, seamless steel pipe cold drawn. The use of the process of the fracture occurred, almost no plastic deformation occurs, are generally brittle fracture. Brittle fracture is caused by a variety of reasons such as: grain boundary has precipitates, regardless of its strength stronger than the matrix strength or weak, are the cause of the crack; grain boundary segregation is also the reason for the fracture; In addition, Even in the far less than the yield limit of the alternating load, it will cause fatigue fracture phenomenon.