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Pickling and heat treatment process of seamless precision steel pipe

Author: Dagang precision tube time: December 21, 2018

 Pickling process of seamless precision steel pipe

   Seamless precision steel pipe Pickling process:

Pickling of seamless precision steel pipe is to soak the carrier with 6mol / L hydrochloric acid for 2h Or concentrated hydrochloric acid heating boiling 30 minutes, filtering, washing with water to neutral, drying. Pickling can remove iron, aluminum, calcium, magnesium and other impurities on the surface, but can not remove the silanol group. The acid washing carrier is suitable for the analysis of acid samples.

The surface of precision seamless steel pipe should be degreased and derusted so as to prepare for the next process. In the production process, the pickling process is to remove the surface oxide scale, then after lubrication treatment, and then draw deep processing.

If the seamless precision steel pipe is not pickled, there may be oxides and oil stains on the surface, which can not be removed by phosphating solution nuclear energy, and the phosphating quality will be reduced.

 Heat treatment process of seamless precision steel pipe

Heat treatment process of seamless precision steel pipe:

Vacuum quenching furnace for seamless precision steel pipe can be divided into oil quenching and gas quenching according to cooling method, and can be divided into single chamber type and double chamber type according to the number of working positions.

Oil quenching is easy to cause surface deterioration of workpiece. In addition, the adhesion of carbon black and oil on the surface is unfavorable to simplify the heat treatment process.

The development of vacuum quenching technology for seamless precision steel pipe mainly lies in the development of air-cooled quenching furnace with excellent performance and single working position. The above-mentioned double chamber furnace can also be used for gas quenching, but the operation of double position type makes it difficult to load the furnace in large quantities, and it is easy to cause workpiece deformation or change workpiece orientation to increase quenching deformation during high temperature movement.


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