Steel pipe difference: the difference between precision steel pipe and spiral steel pipe

   Precision spiral steel pipe is a kind of high-precision steel pipe after cold drawing or hot rolling. Because the inner and outer walls of precision spiral steel pipe have no oxide layer precision spiral steel pipe, high pressure and no leakage, high precision, high smoothness, no cold deformation, flaring, flattening without cracks, etc., it is mainly used to produce pneumatic or hydraulic components. For example, cylinders or cylinders are made of seamless tubes. The chemical composition of precision spiral steel pipe is carbon C, silicon Si, manganese Mn, sulfur S, phosphorus P, chromium Cr.


　　The difference between precision steel pipe and spiral steel pipe


　　1. The main feature of spiral steel pipe is that it has no welded joint and can withstand large pressure. The product can be a very rough cast or cold-draw.


　　2. Precision steel pipes are products that have appeared in recent years, mainly due to strict tolerances and roughness of inner and outer wall sizes.


　　Cold drawn precision steel pipe features


　　1. The outer diameter is smaller.


　　2. High precision can be produced in small batches.


　　3. The cold drawn product has high precision and good surface quality.


　　4. The cross-sectional area of steel pipes is more complicated.


　　5. The performance of steel pipe is superior and the metal is dense.


　　Executive standard


　　GB/T3639


　　GB/T8713


　　DIN2391-2


　　HK15-2000


Steel pipe difference: the difference between precision steel pipe and spiral steel pipe


　　use


　　For the manufacture of mechanical structures, hydraulic equipment, automotive parts


　　delivery status


　　Delivery status code description


Cold working / hard BK is not heat treated after final cold working, so the tube can only be deformed very little


Cold working / soft BKW after the final heat treatment, cold processing of small deformation, when processing the end of the steel pipe


Allow limited cold deformation (eg bending, flare)


After stress relief after cold working, BKS is finally cold worked and annealed below Ac 1 to eliminate cold working stress.


After annealing the final cold working of GBK, the steel tube is completely annealed under a protective atmosphere.


After normalizing the final cold processing of NBK, the normalizing of the steel pipe under protective atmosphere