General
Seamless Steel Pipe production process can be divided into cold-drawn seamless
Steel Pipe and hot-rolled seamless steel pipe. The production process of cold-rolled seamless steel pipe is generally more complicated than hot-rolled steel. The pipe blank must be firstly rolled by three rollers. After pressing, the sizing test is performed. If the surface does not respond to cracks, the circular tube is cut by a mower to cut a blank having a length of about one meter. Then enter the annealing process, annealing with acidic liquids for pickling, pickling should pay attention to the surface whether there is a lot of blistering, if there is a large number of blisters generated that the quality of the steel tube can not meet the standard response. Appearance of cold-rolled seamless steel pipe is shorter than hot-rolled seamless steel pipe, cold-rolled seamless steel pipe wall thickness is generally smaller than the hot-rolled seamless steel pipe, but the surface looks brighter than thick-walled seamless steel pipe, the surface is not too More rough, caliber does not have too many glitches.
The delivery status of hot-rolled seamless steel tubes is generally after hot-rolled and heat-treated. After the hot rolled seamless steel tubes undergo quality inspection, they must be strictly hand-selected by the staff. After the quality inspection, surface oiling is performed, followed by several times of cold drawing experiments, and after the hot rolling treatment, perforation tests are performed. If the perforation enlargement diameter is too large, straightening correction is required. After straightening, it is transported by the transmission device to the flaw detection machine to carry out the flaw detection experiment. Finally, it is labeled and placed in the warehouse after specification.
The above information sources: 51 steel pipe network
