Carbon steel pipe classification: carbon steel pipe can be divided into seamless steel pipe and welded steel pipe points two categories. By the cross-sectional shape can be divided into the tube and shaped tubes, round steel is widely used, but there are some square, rectangular, semi-circular, hexagonal, equilateral triangle, octagon shaped steel tubing. For steel to withstand fluid pressure hydraulic test should be carried out to test its ability to withstand and quality, does not leak under pressure requirements, wet or expansion of qualified, some steel but also according to the requirements of the standard or demand side, curling trials, flaring test, flattening test.

Seamless steel pipe is ingot made of perforated or solid through the capillary tube, and then hot rolled, cold-rolled or cold call is made. Seamless steel pipe with a diameter* thickness specifications expressed in millimeters. Seamless steel pipe is divide into hot and cold seamless steel categories. Hot-rolled seamless steel pipes of general, low, medium pressure boiler pipe, high pressure boiler pipe, steel pipe, stainless steel pipe, oil cracking pipe, steel pipes and other steel and other geological. Cold-rolled subject to sub- general seamless steel pipe, low pressure boiler pipe, high pressure boiler pipe, steel pipe, stainless steel pipe, oil cracking pipe, the other steel, but also thin-walled carbon steel, alloy steel thin-walled, walled stainless steel, special steel pipe.

Welded steel pipe with plate or strip is bent after forming, then made by welding. Press the seam into the form of Longitudinal and spiral welded pipe. Divided into general -use pipe, galvanized pipe, blowing pipe, wire casing, metric pipe, roller pipe, deep well pump tube, automotive tube, transformer tube, welded tube, welding shaped tube and spiral welded pipe.