Specifications for Heat Treatment
1 Scope
This standard specifies technical requirements and inspection methods for the G8Cr15, GCr15, GCr15SiMn, GCr15SiMo and GCr18Mo steel rolling bearing ferrules and rolling elements (hereinafter referred to as "bearing parts"), as specified in GB/T 18254 [1], after annealing, quenching and tempering.
This standard is applicable to interprocess inspection of the said steel bearing parts and heat treatment quality inspection of finished parts (commodities), as well as bearing parts made from other high-carbon chromium steels. For bearing parts subject to special requirements, corresponding product drawings shall apply.
2 Normative References
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 230.1-2009 Metallic Materials—Rockwell Hardness Test—Part 1: Test Method (Scales A, B, C, D, E, F, G, H, K, N, T)
GB/T 231.1 Metallic Materials—Brinell Hardness Test—Part 1: Test Method
GB/T 272-2017 Rolling Bearing—Identification Code
GB/T 1172 Conversion of Hardness and Strength for Ferrous Metal
GB/T4340.1 Metallic Materials—Vickers Hardness Test—Part 1: Test Method
GB/T 6394 Determination of Estimating the Average Grain Size of Metal
GB/T 17394 Metallic Materials—Leeb Hardness Test
GB/T 24606 Rolling Bearings—Non-destructive Testing—Magnetic Particle Testing
JB/T 7361 Rolling Bearings—Test Method for Hardness of Parts
JB/T 7362 Rolling Bearings—Determination of Decarburized Depth for Parts
3 Technical Requirements
3.1 Technical requirements of the bearing parts after spheroidizing annealing
The technical requirements of bearing parts after spheroidizing annealing are as given in Table 1.
3.2 Technical requirements of the bearing parts after martensite quenching and tempering
3.2.1 Hardness
The hardness of bearing part after martensite quenching and tempering, and the hardness difference of the same part respectively shall comply with Tables 2 and 3 respectively.
Foreword i
1 Scope
2 Normative References
3 Technical Requirements
4 Inspection Methods
Annex A (Informative) Effective Wall Thickness of Ferrule and Effective Diameter of Roller
Annex B (Normative) Steel Ball Crushing Load Test Specifications and Crushing Load Value after Heat Treatment
Annex C (Normative) Decarburized Layer Depth of Bearing Part after Quenching and Tempering
Annex D (Informative) Allowable Deformation of Bearing Ferrule after Quenching and Tempering
Annex E (Informative) Residual Austenite Content of Bearing Part after Quenching and Tempering
Annex F (Normative) Hardness Correction of Curved Surface
Annex G (Normative) Pickling Inspection Specifications
Bibliography
Specifications for Heat Treatment
1 Scope
This standard specifies technical requirements and inspection methods for the G8Cr15, GCr15, GCr15SiMn, GCr15SiMo and GCr18Mo steel rolling bearing ferrules and rolling elements (hereinafter referred to as "bearing parts"), as specified in GB/T 18254 [1], after annealing, quenching and tempering.
This standard is applicable to interprocess inspection of the said steel bearing parts and heat treatment quality inspection of finished parts (commodities), as well as bearing parts made from other high-carbon chromium steels. For bearing parts subject to special requirements, corresponding product drawings shall apply.
2 Normative References
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 230.1-2009 Metallic Materials—Rockwell Hardness Test—Part 1: Test Method (Scales A, B, C, D, E, F, G, H, K, N, T)
GB/T 231.1 Metallic Materials—Brinell Hardness Test—Part 1: Test Method
GB/T 272-2017 Rolling Bearing—Identification Code
GB/T 1172 Conversion of Hardness and Strength for Ferrous Metal
GB/T4340.1 Metallic Materials—Vickers Hardness Test—Part 1: Test Method
GB/T 6394 Determination of Estimating the Average Grain Size of Metal
GB/T 17394 Metallic Materials—Leeb Hardness Test
GB/T 24606 Rolling Bearings—Non-destructive Testing—Magnetic Particle Testing
JB/T 7361 Rolling Bearings—Test Method for Hardness of Parts
JB/T 7362 Rolling Bearings—Determination of Decarburized Depth for Parts
3 Technical Requirements
3.1 Technical requirements of the bearing parts after spheroidizing annealing
The technical requirements of bearing parts after spheroidizing annealing are as given in Table 1.
3.2 Technical requirements of the bearing parts after martensite quenching and tempering
3.2.1 Hardness
The hardness of bearing part after martensite quenching and tempering, and the hardness difference of the same part respectively shall comply with Tables 2 and 3 respectively.
Contents of GB/T 34891-2017
Foreword i
1 Scope
2 Normative References
3 Technical Requirements
4 Inspection Methods
Annex A (Informative) Effective Wall Thickness of Ferrule and Effective Diameter of Roller
Annex B (Normative) Steel Ball Crushing Load Test Specifications and Crushing Load Value after Heat Treatment
Annex C (Normative) Decarburized Layer Depth of Bearing Part after Quenching and Tempering
Annex D (Informative) Allowable Deformation of Bearing Ferrule after Quenching and Tempering
Annex E (Informative) Residual Austenite Content of Bearing Part after Quenching and Tempering
Annex F (Normative) Hardness Correction of Curved Surface
Annex G (Normative) Pickling Inspection Specifications
Bibliography
