Measures to Reduce the Quenching Distortion and Bending of SMLS
Sources: this site Click: Date: 2015-11-18 5:18:0
Measures to reduce the quenching distortion and bending of seamless steel pipe
(1) The original organization and the original stress state.
For seamless steel spherical pearlite original organization or shall be quenched, for (machining) deformation before heat treatment should not be straightened.
(2) fully preheated.
Poor thermal conductivity of high alloy steel and seamless steel tubes preheat one or more times, also be segmented heated to the quenching temperature.
(3) Low-temperature quenching.
In ensuring the hardness and technical requirements under the premise of seamless steel pipe as much as possible the use of lower quenching temperature, and appropriate to shorten the holding time.
(4) Select a reasonable cooling method and cooling medium.
Slow cooling should be used in the cooling medium, it is possible to use pre-cooling plus double quenching, quenching or isothermal hardening, small-diameter, high-speed steel drill bit using rubbing straight quenching.
(5) Serious and standard quenching operation.
In the warm-up, the heating and cooling process, vertical hanging and other measures should be adopted to ensure the reduction of the human factor. In the heating and cooling of the session, shall appear side to side, should vertically into the heating and cooling medium, with particular attention to the use of water quenching oil cooling water time and 27simn seamless steel oil quenching oil time.
(6) To strengthen the tempering process and management, seamless steel pipe quench cooling to room temperature, it should be tempered immediately.
(7) A reasonable deformation of straightening.
For quenching and tempering treatment of parts, high-temperature tempering after cold straightening process can be used for seamless steel pipe superplastic (untransformed austenite state) straightened, or stabilization of residual austenite (isothermal hardening) cooling and straightening, for small elongate triangular box pressure straight tempered. Tempering can also use a special jig for straight and so on.
(1) The original organization and the original stress state.
For seamless steel spherical pearlite original organization or shall be quenched, for (machining) deformation before heat treatment should not be straightened.
(2) fully preheated.
Poor thermal conductivity of high alloy steel and seamless steel tubes preheat one or more times, also be segmented heated to the quenching temperature.
(3) Low-temperature quenching.
In ensuring the hardness and technical requirements under the premise of seamless steel pipe as much as possible the use of lower quenching temperature, and appropriate to shorten the holding time.
(4) Select a reasonable cooling method and cooling medium.
Slow cooling should be used in the cooling medium, it is possible to use pre-cooling plus double quenching, quenching or isothermal hardening, small-diameter, high-speed steel drill bit using rubbing straight quenching.
(5) Serious and standard quenching operation.
In the warm-up, the heating and cooling process, vertical hanging and other measures should be adopted to ensure the reduction of the human factor. In the heating and cooling of the session, shall appear side to side, should vertically into the heating and cooling medium, with particular attention to the use of water quenching oil cooling water time and 27simn seamless steel oil quenching oil time.
(6) To strengthen the tempering process and management, seamless steel pipe quench cooling to room temperature, it should be tempered immediately.
(7) A reasonable deformation of straightening.
For quenching and tempering treatment of parts, high-temperature tempering after cold straightening process can be used for seamless steel pipe superplastic (untransformed austenite state) straightened, or stabilization of residual austenite (isothermal hardening) cooling and straightening, for small elongate triangular box pressure straight tempered. Tempering can also use a special jig for straight and so on.
