Technology analysis of bearing steel ball
The preheating before quenching heating: the main purpose is to shorten the time and reduce the heating, quenching deformation and cracking, and also can reduce the tendency to overheat and decarburization, preheating bath furnace is adopted in the process, the temperature is 600 degrees Celsius, preheating 8 - 10 minutes, if the preheating temperature of the box type furnace, in 530 - 550 degrees Celsius time is longer.
Determination of heating time: the heating time of each plant is not exactly the same, generally after preheating heating time is 10 - 15s / mm, box electric furnace for the - 50s / mm. Without preheating salt furnace for 30 - 35S / mm, box furnace for the 90 - 100s / mm. In this example GCr15 bearing ball after preheating in the salt furnace quenching heating time to consider the furnace load take 8 minutes.
The quenching: because GCr15 ball bearing alloy containing more elements to hinder the uniform composition, but also to prevent the deformation of GCr15 bearing steel and have certain toughness and fatigue strength, so the oil cooler