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Standard and production process of precision tube

Author: Dagang precision tube time: March 28, 2019

 Standard of precision tube

   Precision tube Standards for:

1. National standard of precision tube:

GB / t3639-2009, and GB / t8162-2008 structural precision steel pipe may also be used.

2. International standards for precision tubes:

  DIN2391, EN10305-1,EN10305-4, ASTM A519。

 Production process of precision tube

Production process of precision tube:

1. Capillary

The wall thickness of the capillary should be uniform, and the defects on the inner and outer surfaces should be less. The equipment for polishing the outer surface and cleaning the inner hole defects should be equipped.

2. Re inspection

Compared with the common cold drawn steel pipe, the pickling and re inspection process of hot-rolled capillary is added in the production of precision pipe. The main purpose is to ensure that there are no folding and cracks on the outer surface of the capillary, and to eliminate the inner surface defects such as folding, serious scribing and pitting.

3. Annealing

Annealing is a very important process in the production of all cold drawn tubes. The quality of annealing affects not only the performance of steel pipes, but also the removal of scale. Cold drawn precision steel pipe needs to be equipped with non oxidation bright annealing furnace equipment.

 Allowable deviation of precision tube size

Allowable deviation of precision tube size:

Dimension and allowable deviation of precision steel pipe: the general specification of precision steel pipe is 10 * 1-203 * 25, and the tolerance range required by national standard is as follows:

Deviation grade standard outer diameter allowable deviation

  D1 ± 1.5%, minimum ± 0.75 mm

  D2 ± 1.0%。 minimum ± 0.50 mm

  D3 ± 0.75%. Minimum ± 0.30 mm

  D4 ± 0.50%。 minimum ± 0.10 mm


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