Waste heat quenching method of annular forge piece

Abstract

The invention discloses a waste heat quenching method of an annular forge piece, which is characterized in that a ring piece manufacturing process adopting after-forging waste heat quenching is adopted, after-forging waste heat is utilized to quench a ring, so that the after-forging waste heat cannot be wasted, the production cost can be reduced, and due to the fact that the ring does not need to be reheated to quench, the production efficiency is improved. Therefore, the production time can be greatly shortened, and the production efficiency can be improved; besides, in order to enable the ring quenched by the waste heat after forging to have better mechanical properties, the process parameters of the process are improved and refined aiming at the ring pieces with different sizes, so that the product performance is more stable and excellent. The method is suitable for quenching heat treatment of stainless steel ring rolled pieces.

Description

Technical Field

[0001] The present invention relates to a heat treatment method, and particularly to a residual heat quenching method for ring forgings. Background Art

[0002] The existing quenching of ring rolled parts generally adopts the following method: after the ring is rolled, it will be cooled, and then heated for quenching. On the one hand, this will waste the residual heat after forging, resulting in energy loss, thus increasing the production cost. On the other hand, reheating the ring for quenching will greatly increase the production time, thus reducing the production efficiency. Summary of the Invention

[0003] The technical problem to be solved by the present invention is: to provide a residual heat quenching method for ring forgings, which can make the product performance excellent and stable, the production cost low, and the production efficiency high.

[0004] To solve the above problems, the residual heat quenching method for ring forgings of the present invention is characterized by including the following steps:

[0005] Load the steel billet obtained by blanking into the furnace. When loading the steel billet, the temperature in the furnace is ≤750°C. After loading is completed, the temperature in the furnace is raised to 900°C ± 20°C at a rate of ≤180°C / h and held for 2 - 3h. Then, the temperature in the furnace is raised to 1120°C ± 20°C at a rate of ≤180°C / h and held for 0.5 - 1.5h. Then, take out the steel billet for forging; perform forging punching on the heated steel billet; perform ring rolling on the steel billet on a ring rolling machine; after the ring rolling is completed, directly lift the ring to the quenching pool and use the residual heat after forging to perform water cooling quenching on the ring; the quenching pool performs water circulation so that during the quenching process, the water temperature in the quenching pool is 15 - 40°C; the time interval between quenching and tempering is not more than 2h; when loading the ring into the furnace, the temperature in the furnace is ≤400°C. After loading is completed, the temperature in the furnace is raised to 620°C ± 10°C at a rate of ≤150°C / h and held for 6.5 - 7.5h. Then, the ring is air-cooled.

[0006] Further, when the diameter D of the ring is 1.6m < D ≤ 1.8m, the quenching time of the ring is 7s - 10s; when the diameter D of the ring is 1.3m < D ≤ 1.6m, the quenching time of the ring is 6s - 8s; when the diameter D of the ring is D ≤ 1.3m, the quenching time of the ring is 6s - 7s.

[0007] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0008] The residual heat quenching method for the ring forgings of the present invention. The ring manufacturing process using post-forging residual heat quenching quenches the ring using the post-forging residual heat, so that the post-forging residual heat will not be wasted, thereby reducing the production cost. And since there is no need to reheat the ring for quenching, the production time can be greatly reduced, and thus the production efficiency can be improved. In addition, in order to make the ring using post-forging residual heat quenching have better mechanical properties, the process improves and refines the process parameters for different sizes of ring forgings, making the product performance more stable and excellent. Detailed implementation manners

[0009] The residual heat quenching method for the ring forgings of the present invention requires equipment such as a forging heating furnace, a press, a ring rolling mill, and a manipulator. The specific implementation manners are as follows:

[0010] Load the steel billet obtained by blanking into the furnace. When loading the steel billet, the temperature in the furnace is ≤750°C. After loading is completed, the temperature in the furnace is raised to 900°C ± 20°C at a rate of ≤180°C / h and held for 2 - 3 h, then the temperature in the furnace is raised to 1120°C ± 20°C at a rate of ≤180°C / h and held for 0.5 - 1.5 h, and then take out the steel billet for forging; perform forging punching on the heated steel billet; perform ring rolling on the steel billet on the ring rolling mill; after the ring rolling is completed, directly hoist the ring into the quenching pool and use the post-forging residual heat to perform water cooling quenching on the ring; the quenching pool performs water circulation so that during the quenching process, the water temperature in the quenching pool is 15 - 40°C; the time interval between quenching and tempering is not greater than 2 h; when loading the ring into the furnace, the temperature in the furnace is ≤400°C. After loading is completed, the temperature in the furnace is raised to 620°C ± 10°C at a rate of ≤150°C / h and held for 6.5 - 7.5 h, and then the ring is air-cooled.

[0011] When the diameter D of the ring is 1.6 m < D ≤ 1.8 m, the quenching time of the ring is 7 s - 10 s; when the diameter D of the ring is 1.3 m < D ≤ 1.6 m, the quenching time of the ring is 6 s - 8 s; when the diameter D of the ring is D ≤ 1.3 m, the quenching time of the ring is 6 s - 7 s.

Claims

1. A method for residual heat quenching of annular forgings, characterized in that: It includes the following steps: Load the steel billet obtained from blanking into the furnace. When loading the steel billet, the temperature in the furnace is ≤750°C. After loading is completed, the temperature in the furnace is raised to 900°C ± 20°C at a rate of ≤180°C / h and then held for 2 - 3 h. Then, the temperature in the furnace is raised to 1120°C ± 20°C at a rate of ≤180°C / h and held for 0.5 - 1.5 h. Then, take out the steel billet for forging; perform forging punching on the heated steel billet; perform ring rolling on the steel billet on a ring rolling mill; after the ring rolling is completed, directly lift the ring to the quenching pool and use the residual heat after forging to perform water cooling quenching on the ring; circulate the water in the quenching pool so that during the quenching process, the water temperature in the quenching pool is 15 - 40°C; the time interval between quenching and tempering is not more than 2 h; when loading the ring into the furnace, the temperature in the furnace is ≤400°C. After loading is completed, the temperature in the furnace is raised to 620°C ± 10°C at a rate of ≤150°C / h and held for 6.5 - 7.5 h. Then, the ring is air-cooled.

2. The method for quenching the residual heat of the annular forging according to claim 1, characterized in that: When the diameter D of the ring is 1.6 m < D ≤ 1.8 m, the quenching time of the ring is 7 s - 10 s; when the diameter D of the ring is 1.3 m < D ≤ 1.6 m, the quenching time of the ring is 6 s - 8 s; when the diameter D of the ring is D ≤ 1.3 m, the quenching time of the ring is 6 s - 7 s.