The tempering process of the casing Pipe is a heat treatment process of reheating the quenched workpiece to a suitable temperature lower than the lower critical temperature, and cooling to room temperature in a medium such as air or water or Oil after a certain period of time.
The purpose of tempering:
(1) To eliminate the residual stress generated during quenching of the workpiece to prevent deformation and cracking;
(2) To adjust the Hardness, strength, Ductility and toughness of the workpiece to meet the performance requirements;
(3) To stabilize the structure and size, to ensure accuracy;
(4) improve and improve processing performance.
The tempering category of oil casing pipes:
1. Low temperature tempering meaning: refers to the tempering of the workpiece at 150~250 °C.
Objective: To maintain the high hardness and wear resistance of the quenched workpiece and reduce the quench residual stress and Brittleness. After tempering, tempered martensite is obtained, which refers to the structure obtained when the quenched martensite is tempered at low temperature. Applications: cutting tools, measuring tools, molds, rolling bearings, carburizing and surface hardened parts.
2. The meaning of medium temperature tempering: refers to the tempering of the workpiece between 350 ~ 500 °C.