Expansion coefficient of inspection methods can be wiped with soapy water in the joint gap at each annealing furnace to see if run gas; which places are most likely to run gas annealing furnace tube into place and out of the tube where seals are particularly vulnerable to this place wear should always check often change. Presented before the roll forming of precision steel pretreatment technology programs; analysis of the normalizing temperature, holding time and cooling mode on the influence of raw material microstructure and mechanical properties of the tube; normalizing process to determine the conventional precision steel: heating temperature (890 ± 10) ℃, after holding 6min interspersed cooled. Conventional normalizing process can be completely eliminated widmanstatten precision steel to match the yield strength and tensile strength of more reasonable precision seamless gcr15 yield ratio σS / bσ≤0.78, elongation 5δ≥30% 20 Precision None pipe joints, cold forming performance improved significantly and avoid cold-formed crack. Tensile residual stress mainly from tensile residual stress generated in the device during the welding process. Current precision seamless steel tubes, widely used in engineering annealed to eliminate residual stress after welding cooling, and cooling after welding residual stress is an important process, this approach is a waste of energy and prone to large welding residual stress. Post weld heat treatment is a novel technique to eliminate the residual stress. Precision steel before welding to heat treatment temperature after preheating and butt welding process to maintain the temperature of the heating element continuously, after soldering using cotton insulation be incubated allowed to cool slowly. Quenching the steel to increase strength and hardness, but to reduce their plasticity. Quench hardening agent commonly used in water, oil, alkali and salt solutions and the like. Tempering precision steel will have to re-hardened precision steel heated to a certain temperature, and then some method of cooling is called tempering. Its purpose is to eliminate internal stress generated by hardening, reduce the hardness and brittleness, in order to obtain the desired mechanical properties. Tempering points tempering, tempering and tempering categories. Multi-quenching and tempering, normalizing conjunction. After quenching quenching tempering heat treatment method called quenching 16mn precision seamless tube manufacturing chemical composition: C: 0.12 ~ 0.20; Mn: 1.20 ~ 1.60; Si: 0.20 ~ 0.55; tensile strength: 470 ~ 660 N / mm2; yield strength: 275 to 345 N / mm2 16mn precision seamless adjustment is to rely on the carbonaceous (C) amount to improve the mechanical properties of the steel process tube - test - heating - piercing - Pickling - dry lubricant - drawing - solution treatment - Pickling - pickling passivation - test - cold --- cutting head - Polished - test - manufacturing methods: 1,16mn Precision None pipe joints usually in the automatic rolling mill production. Solid tube defects after inspection and clear surface, cut into desired length, end to end in the perforated tube centering surface, and then sent to the furnace heating, perforation on the puncher. While continuing to rotate and move forward in the perforation, in the role of head of the roll and, gradually forming a cavity inside the tube, called capillary. Continue rolling and then sent to the automatic rolling machine. Finally, after all the whole entire thickness of both, the sizing mill sizing, to specifications. The use of continuous production of hot-rolled seamless steel pipe mill is more advanced methods. 2 putting up get smaller size and better quality, seamless, must cold-rolled, cold drawn, or both combined. Cold rolled usually the two-roll mill, steel pipe in the hole section becomes circular hole slot and does not move the cone head composed of rolling. Drawing is usually performed on the 0.5 ~ 100T single chain or double chain drawing machine. 3, extrusion upcoming heating good squeeze tube placed in a sealed cylinder, piercing rod and rod movement squeeze together to make the extrusion die extrusion from the smaller hole. This method can produce smaller diameter steel pipe. High precision seamless virtue of Industry (certified), Precision Seamless Steel Tube Co. Liaocheng provided by virtue of Industry. Liaocheng virtue Pipe Co., Ltd. (www.meidegc.com) (www.meidegc.com) (www.mdwfg.com) (www.mdggc.com) Shandong Liaocheng, steel leader, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. Industry leaders in the United States and Germany with the staff warmly welcome all inquiries negotiations to create the virtues pipe industry a better future.