According to GB/T9711.1 pipeline performance requirements and the different tempering temperature, pipe tempering can be divided into the following:
1. Pipeline low temperature tempering (150-250 degrees)
The low temperature tempering tissue is tempered martensite. Its purpose is to maintain the high hardness of hardened steel and high wear resistance under the premise of reducing its quenching stress and brittleness, so as not to use when the crack or premature damage. It is mainly used for a variety of high-carbon cutting tooling, measuring tools, GB/T9711.1 pipeline steel pipe, rolling bearings and carburizing pieces, tempering hardness is generally HRC58-64.
2. Pipeline temperature tempering (250-500 degrees)
The medium of tempering tempering is tempered. The aim is to achieve high yield strength, elasticity and high toughness. Therefore, it is mainly used for a variety of GB/T9711.1 pipeline steel pipe and hot mold processing, tempering hardness is generally HRC35-50.
3. Pipeline high-temperature tempering (500-650 degrees)
The high temperature tempering organization is tempered sorbite. It is customary to treat quenching and high temperature tempering combined with heat treatment called quenching and tempering treatment, its purpose is to obtain strength, hardness and plasticity, toughness are better comprehensive mechanical properties. Therefore, widely used in automotive, GB/T9711.1 pipeline steel pipe, machine tools and other important structural parts, such as connecting rods, bolts, gears and shafts. After tempering hardness is generally HB200-330.
