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The production process of precision stainless steel seamless steel pipe in general can be divided into two kinds of hot rolling and cold drawing, cold-rolled seamless steel pipe production process than hot-rolled billet to complex, first to three roller rolling and extrusion to sizing test, if the tube through the cutting machine cutting surface without crack response after cutting the billet growth of about one meter. Then enter the annealing process, annealing and pickling to use acid pickling liquid, should pay attention to the surface if there are a lot of bubbling, if there are a large number of bubbling pipe shows that the quality is not up to the standard response. The appearance of cold rolling seamless steel tube shorter than hot-rolled seamless steel pipe, cold rolled seamless steel pipe wall thickness is generally higher than hot-rolled seamless steel pipe to be small, but the surface looks better than thick wall seamless steel pipe is more bright, rough surface is not too much, not too much burr diameter. Hot rolled seamless steel pipe delivery status is generally hot-rolled state after heat treatment delivery. Hot rolled seamless steel tube after quality inspection after staff strict hand picked in quality inspection should be carried out after the oil surface, followed by cold drawing experiments, hot rolling process should be carried out after the perforation experiment, if perforated expanding too large to carry out straightening correction. After straightening, then transferred to the flaw detector by the transport device for testing, and finally labeled, after the specification arranged into the warehouse. Hot rolled round billet, heating, perforation, three roll cross rolling, rolling or extrusion, tube, diameter (or reducing), cooling, straightening, pressure test (or testing), marking and storing seamless steel ingot is made by capillary tube or solid perforation, then hot, cold or cold drawing made. Specification for precision stainless steel seamless steel tubes with external diameter * wall thickness mm. Precision stainless steel seamless steel tube sub hot-rolled and cold-rolled (DIAL) seamless steel pipe two categories. Hot rolled seamless steel tubes are divided into general steel pipe, low and medium pressure boiler steel pipe, high pressure boiler steel pipe, alloy steel pipe, stainless steel pipe, petroleum cracking pipe, geological steel pipe and other steel pipes, etc.. Cold rolled seamless steel pipe (DIAL) in general, steel pipe for low and medium pressure boiler tube, high-pressure boiler steel pipe, alloy steel pipe, stainless steel pipe, oil cracking tube and other steel tube, including carbon thin-walled steel, alloy thin-walled steel, stainless steel, thin steel tube. Hot-rolled seamless pipe diameter is generally greater than 32mm, wall thickness 2.5-200mm, cold-rolled seamless steel pipe diameter can be 6mm, wall thickness can be 0.25mm, thin wall pipe diameter can be less than 5mm 0.25mm wall thickness, cold rolling higher than the high dimensional accuracy.