1. Scope
This Part specifies the main structural type, designation method, –boundary dimension and technical specification of four row cylindrical roller bearings for rolling mills (hereafter simply referred to as bearings).
This Part is applicable to production, inspection and user design, type selection and acceptance of bearings.
2. Normative References
The following normative documents contain provisions which, through reference in this part of JB/T 5389, constitute provisions of this standard. For dated references, subsequent amendments (excluding amending errors in the text) to, or revisions of, any of these publications do not apply. However, all parties coming to an agreement according to this standard are encouraged to study whether the latest editions of these documents are applicable. For undated references, the latest edition of the normative documents referred to applies.
GB/T 272-1993 Rolling bearing—Identification code
GB/T 307.2-2005 Rolling Bearings - Measuring and Gauging Principles and Methods (ISO 1132-2:2001, Rolling Bearings - Tolerances - Part2: Measuring and Gauging Principles and Methods, MOD)
GB/T 3203-1982 Carburizing Bearing - Steel Technical Specification
GB/T 4199-2003 Rolling Bearings - Tolerances - Definitions ISO 1132-1:2000, Rolling Bearings-Tolerances - Part1: Terms and Definitions, MOD);
GB/T 7811-1999 Rolling Bearings - Symbols for Quantities;
GB/T 8597-2003 Rolling Bearings - Rustproof Packaging
GB/T 18254-2002 High-carbon Chromium Bearing Steel
JB/T 1255-2001 Specification for Heat-treatment of Rolling Bearing Parts Made from High Carbon Chromium Steel
JB/T 2974-2004 Rolling Bearings - Identification Code-Supplemental Regulations
JB/T 3573-2004 Rolling Bearings-Measurement Method for Radial Clearance
JB/T 3574-1997 Rolling Bearings - Product mark
JB/T 8881-2001 Rolling Bearing Parts - Carburizing Heat Treatment Technical Specification
JB/T 8921-1999 Inspection Rules for Rolling Bearings and Its Commercial Parts
3. Symbols
For the purpose of this Part, the following symbols and those given in GB/T 7811 and GB/T 4199 apply.
di: the nominal diameter of inner ring raceway
Vdisp: the variation of inner ring raceway diameter in a single plane
△dis: the diameter deviation of inner ring raceway
D1mpmax-D2mpmin: the difference between the maximum mean outside diameter and minimum mean outside diameter of the same bearing outer ring
d1pmax-d2mpmin: the difference between the maximum mean inner diameter and minimum mean inner diameter of the same bearing inner ring
dimp-dimp': the difference between the average diameter of inner ring raceway both ends
E: the nominal width of inner ring raceway
Li: the straightness of inner ring raceway
r: the nominal chamfer of inner ring
r1: the nominal chamfer of outer ring
r1smin: the smallest single chamfer dimension of outer ring Sdi: the verticality of inner ring raceway to benchmark end face
4 Main Structural Types
See Figure 1~Figure 3.
5 Designation
5.1 Constitution of designation
Bearing -desigantion consists of type code, dimension code and Suffix Code, and its arrangement sequence is as follows:
Type Code Dimension Code –SuffixCode
5.2 Type Code
Type codes consist of Latin capital letters and represent the constructional features of bearings. See Table 1.
Table 1 Type Codes
Contents
Foreword I
1. Scope
2. Normative References
3. Symbols
4 Main Structural Types
5 Designation
5.1 Constitution of Code
5.2 Type Code
5.3 Dimension Code
5.4 Suffix Code
5.5 Mark Example
6. Boundary Dimension
7. Technical Requirements
7.1 Tolerance
7.2 Clearance
7.3 Material and Heat Treatment
Others
8. Inspection Methods
9. Inspection Rules
10. Marking, Rustproof and Packaging
Appendix A (Normative) Technical Requirements for Commercial Bearing Inner Ring
A.1 Structural Type of Inner Ring of Commercial Bearing
A.2 Code of Inner Ring of Commercial Bearing
A.3 Boundary Dimension of Inner Ring of Commercial Bearings
A.4 Tolerance of Inner Ring of Commercial Bearing
Appendix B (Normative) Recommended Value of Oil Hole Dimension of Outer Ring
B.1 Structural Type of Oil Gallery of Outer Ring
B.2 Oil Gallery Dimension of Outer Ring
