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Summary of the advantages and disadvantages of cold drawn steel pipe and extraction method

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Summary of the advantages and disadvantages of cold drawn steel pipe and extraction method

Date of release:2018-09-27 Author: Click:

Advantages of cold drawn steel pipe:

(1) The size is accurate and the tolerance is small;

(2) When the die hole is processed well and the lubrication is good, the surface quality of the steel pipe is good, and the finish can reach seven grades;

(3) It can be used to produce steel pipes of small diameter and special section;

(4) Since the cold working contributes to the grain refinement of the metal, and the corresponding heat treatment system, a steel pipe with good comprehensive mechanical properties can be obtained;

(5) The equipment is simple, the production method is flexible, and the replacement is convenient.

Disadvantages of cold drawn steel pipe: small deformation, slow speed, large metal consumption, complicated production process and high cost.

Drawing method of cold drawn steel pipe

The most commonly used method for drawing cold drawn steel tubes is coreless drawing (empty drawing) and short mandrel drawing. When the long mandrel is drawn, the tube and the long core are simultaneously passed through the die hole. Compared with the short mandrel drawing, the frictional force of the pipe on the contact surface with the long mandrel is significantly reduced, the deformation resistance is high, and the inner surface is lubricated. For small diameter steel pipes with difficulty, the long core rod can be drawn with a larger wall thickness reduction factor, but after the drawing, the stripping process and a series of rod removing devices are added. This method is only needed when it is especially needed. use.


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