Standard No.:	GJB 269A-2000
English Name:	General specifications for aerospace rolling bearings
Chinese Name:	航空滚动轴承通用规范
Professional Classification:	GJB    Professional Standard - Military
Issued on:	2000-04-24
Implemented on:	2000-9-1
Status:	valid
Target Language:	English
File Format:	PDF
Word Count:	32000 words
Translation Price(USD):	960.0
Delivery:	via email in 1 business day

GJB 269A-2000 The general specification for aerospace rolling bearings 1 Scope 1.1 Subject content This specification specifies the technical requirements, inspection methods, quality assurance and delivery preparation of aerospace rolling bearings (hereinafter referred to as bearings). 1.2 Application scope This specification is applicable to the trial production, production, inspection and acceptance of aerospace bearings and their commercial parts. 2 Normative references GB 304.10-89 Spherical plain bearings - Tolerances GB/T 307.1-94 Rolling bearings - Radial bearings - Tolerances GB/T 307.2-95 Rolling bearings - Measuring and gauging principles and methods GB/T 307.3-96 Rolling bearings - General technical regulations GB/T 307.4-94 Rolling bearings - Thrust ball bearings - Tolerances GB 308-89 Rolling bearings - Steel balls GB 309-84 Rolling bearings - Needle rollers GB 4661-89 Rolling bearings - Cylindrical rollers GB 8597-88 Rolling bearings - Packaging and packing GJB 1765-93 Marking for package of military supplies JB/T 1460-92 Specifications for heat-treatment of rolling bearing parts made from high carbon chromium stainless steel JB/T 2850-93 Rolling bearings - Parts made from Cr4Mo4V bearing steel elevated temperature - Specification for heat-treatment JB/T 3573-93 Rolling bearings - Methods for the measurement and evaluation of radial internal clearance JB/T 3574-92 Rolling bearings - Marking for products JB/T 5313-91 Rolling bearings - Measuring methods for vibration (velocity) JB/T 5314-91 Rolling bearings - Measuring methods for vibration (acceleration) JB/T 6641-93 Rolling bearings - Residual magnetism and its assessment method JB/T 7361-94 Rolling bearings - Test method for hardness of parts JB/T 7752-95 Sealed deep groove ball bearings - Specifications JB/T 8921-1999 Rolling bearings and commercial parts - Inspection rules ZJB J10003-87 Technical conditions for plating quality inspection of silver-plated cages for military bearings ZJB J11038-93 Rolling bearings for military use - Heat treatment quality requirements for parts made from high carbon chromium bearing steel ZJB J11044-98 Code designation method for military rolling bearings 3 Requirements 3.1 Qualification The products delivered according to this specification shall be products that have been qualified or approved. 3.2 General requirements This specification, based on the characteristics of aerospace bearings, supplements the current national standards such as GB/T 307.1, GB/T 307.2, GB/T 307.3, GB/T 307.4, GB 308, GB 309, and GB 4661, while also adding some special requirements for aerospace bearings. 3.2.1 Materials 3.2.1.1 The bearing rings and rolling elements trial-produced and produced in accordance with this specification shall be made of Group A bearing steel, stainless steel, or high-temperature bearing steel. Other materials may also be used if required by the orderer. 3.2.1.2 Materials for bearing parts (including commercial parts) shall comply with the requirements of Annex E "Aerospace bearing materials and material standards" hereof and the relevant product drawings. 3.2.1.3 After materials are received, the manufacturer shall conduct re-inspection according to the corresponding material standards. Production may proceed only after the materials have passed re-inspection. 3.2.2 Product drawings 3.2.2.1 Bearings trial-produced and produced in accordance with this specification shall comply with the requirements of the product drawings. 3.2.2.2 For changes to the drawings of batch-produced bearings that involve performance or fitting dimensions, the manufacturer shall negotiate and reach an agreement with the orderer and obtain the consent of the military representative stationed at the factory. The revised drawings shall be provided to the orderer. For general changes, the orderer and the military representative stationed at the factory shall be notified of the change results. 3.2.2.3 When required by the orderer, the manufacturer shall provide the bearing product drawings to the orderer. 3.2.3 Heat treatment and hardness of bearing parts 3.2.3.1 Heat treatment of bearing parts 3.2.3.1.1 Cold treatment shall be applied to rings and rolling elements of Grade 4(C) bearings [including Grade 5(D) miniature bearings] made of Group A bearing steel without high-temperature tempering, and of bearings made of stainless steel. The cold treatment temperature shall be controlled below -55℃, with a holding time of not less than 1h, to ensure the dimensional stability of the bearing parts. 3.2.3.1.2 Supplementary tempering shall be performed on 100% of rings and rolling elements to eliminate grinding stress. 3.2.3.1.3 The quenched and tempered microstructure of rings and rolling elements made of Group A bearing steel, stainless steel, and high-temperature bearing steel, as well as the crushing load values of steel balls, shall meet the requirements of ZJB J11 038, JB/T 1460, and JB/T 2850. 3.2.3.2 Hardness of bearing parts 3.2.3.2.1 Unless otherwise specified, the hardness of rings and rolling elements made of Group A bearing steel, stainless steel, and high-temperature bearing steel shall meet the requirements of Table 1. Table 1 HRC 3.2.3.2.2 Where bearing rings and rolling elements are made of other materials, their hardness shall meet the requirements of the product drawings. 3.2.3.2.3 The hardness of bearing rings and rolling elements subjected to high-temperature tempering shall meet the requirements of Table 2.

Contents 1 Scope 1.1 Subject content 1.2 Application scope 2 Normative references 3 Requirements 3.1 Qualification 3.2 General requirements 3.3 Detailed requirements 4 Quality assurance requirements 4.1 Inspection responsibility 4.2 Inspection classification 4.3 Inspection conditions 4.4 Qualification inspection 4.5 Quality consistency inspection 4.6 Inspection methods 5 Delivery preparation 5.1 Protective packaging 5.2 Packaging and transportation 5.3 Marking 6 Instructions 6.1 Intended use 6.2 Contents of order documents 6.3 Service life 6.4 Others Annex A (Supplementary) Special supplementary technical requirements for individual bearings Annex B (Supplementary) Bearings with special clearance requirements Annex C (Supplementary) Tolerances of Class 6(E) tapered roller bearings Annex D (Supplementary) Bearing clearance standard Annex E (Supplementary) Aerospace bearing materials and material standards Annex F (Supplementary) Comparison table of supplementary bearing codes in new and old standards Additional explanation