Oil CasOil Casing Pipe Tempering Process and Categorying Pipe Tempering Process and Category

The tempering process of casing is to reheat the quenched workpiece to a proper temperature lower than the lower critical temperature, and cool it to room temperature in air, water or oil and other media after a certain time.
Purpose of tempering:
(1) eliminate the residual stress produced in the process of quenching to prevent deformation and cracking;
(2) adjust the hardness, strength, ductility and toughness of the workpiece to meet the performance requirements;
(3) stabilize the structure and size to ensure the accuracy;
(4) improve and improve processing performance.


Tempering category of oil casing:
1. Meaning of low temperature tempering: it refers to tempering the workpiece at 150-250 ° C.
Objective: to keep the high hardness and wear resistance of quenched workpiece, and reduce the residual stress and brittleness of quenched workpiece. After tempering, the tempered martensite is the structure obtained by tempering the quenched martensite at low temperature.
Application: cutting tools, measuring tools, dies, rolling bearings, carburized and case hardened parts.
2. Meaning of medium temperature tempering: it refers to tempering the workpiece between 350 ° C and 500 ° C.