What is the production process of seamless steel tube

Seamless steel tube plays an important role in production and life. What is the production process of seamless steel tube?

① Main production process of hot-rolled seamless steel tube (△ main inspection process):
Preparation and inspection of tube blank △ → heating of tube blank → piercing → rolling of tube → reheating of steel tube → sizing (reducing) → heat treatment △ → straightening of finished tube → finishing → inspection △ (nondestructive, physical and chemical, bench inspection) → warehousing

② Main production process of cold-rolled (drawn) seamless steel tube:
Billet preparation → pickling and lubrication → cold rolling (drawing) → heat treatment → straightening → finishing → inspection

The general production process of seamless steel tube can be divided into cold drawing and hot rolling. The production process of cold-rolled seamless steel tube is generally more complex than hot rolling. The tube blank shall be continuously rolled with three rollers first, and 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 the steel tube can not meet the corresponding standards. 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.