Views:229 Author:Site Editor Publish Time: 2019-10-17 Origin:Site
Cold drawn seamless pipe is a steel pipe with no joints on the whole steel pipe surface produced by drawing, extrusion, perforation, etc. It is a circular, square, rectangular steel with a hollow section and no seams around it.
Cold drawn steel pipe is a precision cold drawn seamless pipe for mechanical structure, hydraulic equipment with high dimensional accuracy and good surface finish. The use of precision cold drawn seamless tubes to manufacture mechanical structures or hydraulic equipment can greatly save machining time, improve material utilization, and improve product quality.
Cold drawn steel pipe, cold rolled steel pipe unit is a complete set of equipment for producing pipes by cold rolling, cold drawing or cold rolling combined with cold drawing. It is a unit for deep processing of hot rolled pipe or welded pipe.
1) stock preparation: the round tube embryo is cut into a blank having a length of about 1 meter by a cutting machine, and sent to the furnace through a conveyor belt;
2) heating: the billet is sent into the furnace for heating at a temperature of 1100- 1200 ° C, the fuel is hydrogen or acetylene;
3) Perforation: After the round tube blank is discharged, it is subjected to a pressure punching machine for piercing. The perforating machine used is a conical roller punching machine.
7) multi-pass cold drawing;
8) heat treatment;
10) flaw detection; ;
We need to pay attention to the following factors：
1. Capillary tube
The wall thickness of the capillary tube should be uniform, and the surface defects on the inner and outer surfaces should be small; the outer surface polishing and inner hole collapse cleaning equipment should be arranged.
Compared with ordinary cold drawn steel pipe, cold drawn precision seamless pipe production adds hot-rolled capillary pickling and re-inspection process, mainly to ensure that there are no defects such as folding and crack on the outer surface of the pipe, and the inner surface is excluded from folding and severely scratched. Defective capillary tube
Generally, the surface finish of tools used in the production of cold-drawn precision seamless steel tubes is required to be above Ra0.4, the dimensional accuracy is above H13, and the hardness is required to be above HRC70. At the same time, it is required that there is no sticking of the head or the mold shell during the drawing process.
Oxidizing bright annealing furnace equipment. Annealing is a very important process in the production of all cold drawn seamless tube. The quality of the annealing affects both the performance of the steel tube and the removal of the scale. Cold drawn precision steel tubes require a non-oxidizing bright annealing furnace equipment. Qualified cold drawn seamless tube suppliers must take all these factors into consideration during production.