Bearing steel processing standards

GCr6 features: has good cold deformation plasticity and sexual cutting can be salt, NSK bearings wear resistance than high carbon tool steel, but high susceptibility to form white, poor weldability. When heat treatment of low temperature tempering brittleness tendency; Hardenability is poor, in sandstones, critical hardening is about 5 ~ 20 mm diameter ( 50% martensite) 。 It is common used after quenching and low temperature tempering. Application: suitable for manufacturing of small diameter on the rolling bearing steel ball, roller, needle, etc. GCr9 characteristics: compared with GCr6 steel, wear resistance and high hardenability, in oil critical hardening (12 ~ 38 mm diameter 50% martensite) ; Machinability is good, organization of spheroidal pearlite, cold deformation and plastic medium; But poor weldability, and with white dots form is more sensitive, NTN bearing heat treatment sometimes temper brittleness tendency, generally used after quenching and low temperature tempering. Application: suitable for small size on the rolling bearing steel ball and roller, can also be used in the manufacture of high wear resistance, high elastic limit, high contact fatigue strength of other parts. GCr9SiMn features: mechanical properties and wear resistance and GCr15 steel similar, but there is a higher hardenability and good process performance, in oil critical hardening (60 ~ 110 mm diameter 50% martensite) ; Poor weldability, cold deformation and plastic medium, sensitive to white dot form, have a tendency to temper brittleness, commonly used after quenching and low temperature tempering. USES: applicable to manufacture large size of bearing ring instead of GCr15 steel. Bearing steel GCr15 one of the most commonly used, INA bearings have high hardenability, in oil critical hardening of about 18 ~ 40 mm diameter ( 50% martensite) ; After heat treatment can obtain high and even hardness and wear resistance; Fatigue life long, cold deformation and plastic medium, machinability, indirect, sensitive to white dot form, has the temper brittleness, commonly used after quenching and low temperature tempering. Application: suitable for high speed and high load of large-scale machinery used on steel ball bearings, roller and ring; Can also be used in the manufacture of under high load, high wear resistance, high bearing high elastic limit and contact fatigue strength of machine parts and various precision measuring tool, cold punching die, general tools, etc. ; After carbonitriding treatment can be used to make high wear resistance, heat resistance and high dimension stability and service life requirements parts. GCr15SiMn features: than GCr15 steel has higher wear resistance and hardenability, IKO bearings in oil critical hardening diameter of about 90 ~ 110 mm ( 50% martensite) And other features are similar, generally used after quenching and low temperature tempering. Usage: suitable for manufacturing large or very large bearing steel ball, roller and ring, can also be used in the manufacture of high hardness, high wear resistance of mechanical parts and tools. Bearing parts, although has simple structure, high technical requirements, and therefore has the following several machining features: 1. Precision machined bearing parts most of the surface to after grinding, grinding size and geometric accuracy are in microns, especially ring raceway and rolling body of higher precision, superfinishing or grinding processing. 2. Bearing parts processing various process demanding, the production process will be more. General bearing production need 20 ~ 40 working procedure, much more than 70. 3. Processing of bearing parts work is rotary forming on the surface, suitable for molding in processing. Such as forged ring groove rolling mill and car, is the forming tool or prevent plate processing. In addition, the vast majority of the bearing are standardized products, the same type of bearing demand is very big, in order to improve the productivity, reduce costs, ensure the quality and the widespread adoption of new technology, improve the level of mechanization and automation, bearing company usually is according to the bearing types and varieties for mass production, even can establish special automatic line or lines of production