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(1) Pipe material supply, the pipe materials used are hot-rolled finished pipes or semi-finished pipes, extruded pipes and welded pipes; (2) Pipe material preparation, including inspection, bundling, pickling, cleaning, rinsing, neutralization, drying, lubricant application, etc.;
(3) Cold working (cold rolling or cold drawing);
(4) Finished product finishing includes finished product heat treatment, straightening, sampling, head and tail cutting, inspection (manual inspection and various flaw detection), hydraulic test, oiling, packaging, warehousing, etc. Different products have different finishing contents.
     Cold drawn pipe is a type of steel pipe, that is, it is classified according to different production processes, which is different from hot rolled (expanded) pipe. It is processed through multiple passes of cold drawing during the diameter expansion process of the raw tube blank or raw material pipe, usually on a 0.5 to 100T single-chain or double-chain cold drawing machine. In addition to general steel pipes, low- and medium-pressure boiler steel pipes, high-pressure boiler steel pipes, alloy steel pipes, stainless steel pipes, petroleum cracking pipes, machined pipes, thick-walled pipes, small-diameter cold-drawn pipes with internal molds and other steel pipes, cold-rolled (drawn) steel pipes also include carbon thin-walled steel pipes, alloy thin-walled steel pipes, stainless thin-walled steel pipes, and special-shaped steel pipes.
      For more information about cold drawn tubes, please consulthttp://www.fdzsw.cn