Cold rolling of stainless steel engineering pipe refers to cold-drawing, cold-bending, cold-drawing and other cold processing of steel strips into stainless steel pipes at room temperature. Advantages: fast forming speed, high output, and without damaging the coating of stainless steel pipes, can be made into a variety of cross-section open forms to meet the needs of the use conditions; cold rolling can cause large plastic deformation of stainless steel pipes, thereby improving The yield point of the stainless steel tube.
Disadvantages of cold-rolling stainless steel engineering tubes: Although there is no thermal plastic compression during the forming process, residual stress still exists in the section, which will affect the overall and local buckling characteristics of stainless steel tubes.
Advantages of stainless steel engineering pipe hot rolling: It can destroy the casting structure of steel ingots, refine the grains of steel, and remove the defects of microstructure, so that the stainless steel pipe has a dense structure and improved mechanical properties. This improvement is mainly reflected in the rolling direction, so that the stainless steel pipe is no longer an isotropic body; bubbles, cracks and looseness formed during casting can also be welded under the action of high temperature and pressure.
Disadvantages of hot rolling of stainless steel engineering pipes: After hot rolling, non-metallic inclusions (mainly sulfides and oxides, and silicic acid) inside the stainless steel pipes are pressed into thin slices, and delamination (interlayer) occurs. Delamination greatly deteriorates the tensile properties of the steel along the thickness direction, and interlayer tearing may occur when the weld seam shrinks. The local strain induced by the shrinkage of the weld often reaches several times the yield point strain, which is much larger than the strain caused by the load.