Precision bright seamless steel pipe is a high-precision steel pipe material processed by fine drawing or cold rolling. Because the inner and outer walls of the precision bright tube have no oxide layer, bear high pressure without leakage, high precision, high finish, cold bending without deformation, flaring, flattening without cracks, etc., it is mainly used to produce pneumatic or hydraulic components such as cylinder The cylinder can be a seamless tube or a welded tube. The chemical composition of the precision bright tube is carbon C, silicon Si, manganese Mn, sulfur S, phosphorus P, chromium Cr. Introduction to the precision bright tube process: 　　 high-quality carbon steel, finish rolling, non-oxidizing bright heat treatment (NBK state), non-destructive testing, the inner wall of the steel pipe is brushed with special equipment and subjected to high pressure washing, the steel pipe is rust-proofed with anti-rust oil, and both ends are sealed Make dustproof treatment. Main features of precision bright tube: 　　 The inner and outer walls of the steel pipe have high precision and high smoothness. After heat treatment, the steel pipe has no oxide layer, and the inner wall has high cleanliness. The steel pipe bears high pressure, cold bending does not deform, flaring and flattening without cracks, and can make various complex deformations. And mechanical processing. Steel tube color: bright white with high metallic luster.　　The main purpose of the precision bright tube: 　　Automobiles, machine parts and other machinery that have high requirements on the precision and smoothness of the steel pipe. Nowadays, users of precision steel pipes are not only users who have relatively high requirements for precision and smoothness. Because precision bright seamless steel pipes have high precision and tolerances can be maintained at 2--8 wire, many machining users are Time loss, seamless steel pipes or round steel are slowly being transformed into precision bright seamless steel pipes. Common specifications for precision bright tubes 10# 0.07~0.13 0.17~0.37 0.35~0.65 ≤0.035 ≤0.035 　　20# 0.17~0.23 0.17~0.37 0.35~0.65 ≤0.035 ≤0.035 　　35# 0.32~0.39 0.17~0.37 0.35~0.65 ≤0.035 ≤0.035 45# 0.42~0.50 0.17~0.37 0.50~0.80 ≤0.035 ≤0.035 　　40cr 0.37~0.44 0.17~0.37 0.50~0.80 ≤0.035 ≤0.035 0.08~1.10 　　25Mn 0.22~0.2 0.17~0.37 0.70~1.00 ≤0.035 Mn ≤5 0.30 ≤0.2537 ≤0.035 　~0.39 0.15~0.30 1.20~1.50 ≤0.015 ≤0.020 　　 Seamless bright tube bearing pressure calculation formula 1: Knowing the seamless bright tube outer diameter specification wall thickness to be able to bear the pressure calculation method (precision bright seamless steel tube tensile strength of different materials Different) Pressure=(Wall thickness*2*Steel pipe material tensile strength)/(Outer diameter*Coefficient) 　　2: The calculation method for calculating the wall thickness of the known precision bright seamless steel pipe outside diameter and pressure: 　　Wall thickness=(pressure*outside Diameter*factor)/(2*steel tube material tensile strength) 　　3: Expression method of pressure coefficient of precision bright seamless steel tube: 　　 pressure P<7Mpa coefficient S=8 　　7< steel pipe pressure P<17.5 coefficient S=6 　　 pressure P>17.5 S=4