What is the production process of seamless steel pipe?

The production process of general seamless steel pipe can be divided into cold drawing and hot rolling. The production process of cold-rolled seamless steel pipe is generally more complex than hot rolling. The tube blank shall be continuously rolled with three rollers first, and then the sizing test shall be carried out after extrusion. If there is no response crack on the surface, the round tube shall be cut by the cutter, and the billet with a growth of about one meter shall be cut.

Then enter the annealing process. Acid pickling shall be carried out with acid liquid for annealing. When pickling, pay attention to whether there are a lot of bubbles on the surface. If there are a lot of bubbles, it means that the quality of steel pipe can not meet the response standard.

The appearance of cold-rolled seamless steel tube is shorter than that of hot-rolled seamless steel tube. The wall thickness of cold-rolled seamless steel tube is generally smaller than that of hot-rolled seamless steel tube. However, the surface of cold-rolled seamless steel tube is brighter than that of thick-walled seamless steel tube. The surface is not too rough, and the diameter is not too burr.

The delivery state of hot-rolled seamless steel pipe is generally after heat treatment. The hot-rolled seamless steel pipe shall be strictly selected by the staff after the quality inspection. After the quality inspection, the surface shall be coated with oil, followed by many cold drawing experiments. After the hot-rolled treatment, the perforation experiment shall be carried out. If the perforation diameter is too large, the straightening correction shall be carried out.

After straightening, it is transmitted to the flaw detector by the transmission device for flaw detection test, and finally it is labeled and placed in the warehouse after specification arrangement.