100 X 50 SS430 Stainless Steel Rectangular Pipe Galvanized 8K Polished GOST 9941

430 Brushed, Mirror 8K Polised Alloy Steel Tube in Seamless or Welded Tube /Rectangular Tube Stainless Steel

Cold drawn steel pipe and hot rolled steel pipe difference

Cold drawn steel tube

It is in the normal temperature environment, after a series of cold drawing, cold bending and so on technology, processed into a kind of steel. Compared with cold-drawn steel pipe, it is a kind of steel processed above the recrystallization temperature.

The difference between 1

Hot rolling (extruded seamless steel tube) round tube billet → heating → perforation → three-roll cross rolling, continuous rolling or extrusion → tube stripping → sizing (or reducing) → cooling → blank tube → straightening → water pressure test (or defect detection) → marking → storage.
Cold drawing (rolling) seamless steel tube round tube billet → heating → perforation → heading → annealing → pickling → oiling (copper plating) → multi-pass cold drawing (cold rolling) → blank tube → heat treatment → straightening → water pressure test (flaw detection) → marking → storage.
The difference between two

When making cold-drawn steel pipe, its section can have a certain degree of bending, bending is conducive to the bearing capacity of cold-drawn steel pipe. However, in the production of hot rolled pipe, its section is not allowed to have local bending phenomenon, which will affect its service life.

The difference between 3

As the production process of cold drawn steel pipe and hot rolled pipe is different, so their dimensional accuracy and surface finish are also different. Generally speaking, cold-drawn steel tubes have higher precision and better surface finish than hot-rolled tubes.

The difference between 4

The production process of cold-drawn steel pipe is different from that of hot-rolled steel pipe. The production and molding of cold-drawn steel pipe requires the finishing process, heating treatment, perforation technology, hot rolling process, beating treatment, pickling engineering, phosphating treatment, cold drawing process, annealing treatment, straightening treatment, pipe cutting process, inspection of finished products and packing treatment. As for hot-rolled pipe, the finishing process, heating treatment, perforation molding, rolling treatment, sizing treatment, cold bed treatment, straightening treatment, switching treatment, and the final inspection and packaging are needed. It can be seen from these introductions that there are certain differences in their process procedures.

The difference between 5

The cross section distribution of cold-drawn steel pipe and hot-rolled steel pipe is also different, because the reasons for residual stress are different when forming. This results in some bending of the residual stress of the section of cold-drawn steel pipe, while the residual stress of hot-rolled steel pipe is thin film type.

The difference between 6

Because the production process of hot rolled pipe and cold drawn steel pipe is different, so the hot rolled pipe sold in the market is divided into hot rolled seamless steel pipe and hot rolled welded steel pipe; Cold-drawn steel pipe can be divided into cold-drawn seamless steel pipe and cold-drawn welded steel pipe, cold-drawn seamless steel pipe can be divided into circular pipe and special-shaped pipe these two kinds.