When the forgings are quenched, iron chains are used to hoist the forgings horizontally into the water, resulting in a large amount of steam generated after the lower surface enters the water cannot be discharged in time, forming a steam film, resulting in slow cooling of the lower surface of the forgings, affecting its performance. Moreover, more steam accumulates, causing the forging to vibrate, and there are great hidden dangers.
The steam generated by the stem cannot be discharged in time, and the steam on the lower surface accumulates to form a steam film, which plays a role in cooling and protecting the forgings, seriously reducing the cooling speed of the forgings, resulting in a large amount of ferrite in the lower surface tissue, and some of them are reticulated. In order to meet the performance requirements of plate forgings, the problem of uneven quenching and cooling rates should be solved.
According to the characteristics of plate forgings, use the iron chains of the existing spreader in the workshop to hang the forgings, lower the iron chains, and at the same time, the crane deviates to one side, and then lift the forgings. At this time, the surface of the forging and the heat treatment trolley are controlled to be 30-45. Finally, hang it to the water tank and quench it.
When hoisting off-center, the angle between the forging and the trolley surface should be less than 45°. If the angle is too large, it will cause the iron chain and the forging to slide, causing accidents. If the angle is too small, it is found that the steam discharge is relatively narrow and the cooling effect is not good in practical applications. Should try to control in 30-45.
Principle Since the forging is at a certain angle to the ground, after the forging enters the water, the resistance of the steam formed on the lower surface is reduced, and the water in the tank is circulating water, and the flow of water will easily take away the steam on the lower surface, thus improving the The cooling speed of the lower surface of the forging ensures uniform cooling of the whole forging.
The above quenching method improves the cooling rate of the lower surface of the plate forging and ensures uniform cooling of all parts of the forging.