GB/T 305-2019 in English

《GB/T 305-2019滚动轴承 向心轴承止动槽和止动环 尺寸、产品几何技术规范（GPS）和公差值》由TC98（全国滚动轴承标准化技术委员会）归口，主管部门为中国机械工业联合会。

Rolling bearings - Snap ring grooves and snap rings for radial bearings - Dimensions, geometrical product specifications (GPS) and tolerance values

1 Scope

This International Standard specifies the snap ring groove dimensions and tolerance values, chamfer dimensions on the snap ring groove side of the outer ring, and the snap ring dimensions and tolerance values for radial bearings in the dimension series 18 and 19 and the diameter series 0, 2, 3, and 4 (except dimension series 00, 82, and 83), as specified in ISO 15[1].

This standard is applicable to snap ring grooves and snap rings for axial positioning of radial bearings, and is used for the manufacturer on the design, inspection and acceptance of them.

2 Normative references

The following referenced documents are indispensable for the application of this document. For dated reference, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

ISO 582 Rolling bearings - Chamfer dimensions - Maximum values
ISO 1101 Geometrical product specifications (GPS) - Geometrical tolerancing - Tolerances of form, orientation, location and run-out
ISO 5593 Rolling bearings - Vocabulary
ISO 14405-1 Geometrical product specifications (GPS) - Dimensional tolerancing - Part 1: Linear sizes
ISO 15241 Rolling bearings - Symbols for physical quantities

3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 1101, ISO 5593 and ISO 14405-1 apply.

4 Symbols

See Figures 1 to 3 and Table 1.

To express that the geometrical product specification (GPS) system is applied, the dimensional and geometrical characteristics shall be included in the technical product documentation (for example, on the drawing). The dimensional and geometrical specifications associated with them are described in Table 1.

A tolerance value associated to a characteristic is symbolized by t followed by the symbol of characteristic, for example tΔas.

In this International Standard, the ISO default specification operator for size is in accordance with ISO 14405-1, i.e. the two-point size is valid.

In Tables 2 to 5, A.1, A.2, B.1, and B.2, the symbols U and L are used as follows:

U——upper limit deviation;

L——lower limit deviation.

An example of a real drawing indication is given in Annex E.



Figure 1 Snap ring



Figure 2 Mounted snap ring



Note: Regarding "UZ", refer to ISO 1101:2012, 10.2.




Figure 3 Snap ring groove and chamfer

Table 1 Symbols for nominal dimensions, characteristics, and specification modifiers

Foreword i
Introduction iii
1 Scope
2 Normative references
3 Terms and definitions
4 Symbols
5 Snap ring groove and chamfer dimensions and tolerance values
6 Snap ring dimensions and tolerance values
7 Example of marking
Annex B (Informative) Snap ring dimensions and tolerance values for radial bearings, D < 30 mm
Annex C (Informative) Material of snap ring
Annex D (Informative) Application example
Annex E (Informative) Example of drawing indications of characteristics with specification for a snap ring groove
Bibliography