For needle roller bearing, GB T 309 is the governing document for the dimensions listed below. Mechanical and performance requirements for this part family are set by its own standards, not by the bolt and screw property-class documents.
GB T 309 — Scope
The table below lists the dimensions catalogued for needle roller bearing — iso / din (series 133) under GB T 309. The scope of GB T 309 itself is not summarised here — where a figure matters, confirm it against the published document.
Tolerance & Product Grades
Product grade is a concept from dimensional fastener standards and does not apply to GB T 309. Tolerances for this part are the limits shown against each dimension in the table.
Dimensions Specified by GB T 309
| Bore d (mm) | Outer diameter D (mm) | Width B (mm) | Dynamic load C (kN) | Reference standard |
|---|---|---|---|---|
| 8 | 15 | 12 | 7.2 | ISO 1206 / GB/T 309 |
| 10 | 17 | 12 | 8.3 | ISO 1206 / GB/T 309 |
| 12 | 19 | 12 | 9.65 | ISO 1206 / GB/T 309 |
| 15 | 23 | 12 | 12.5 | ISO 1206 / GB/T 309 |
| 20 | 28 | 16 | 18.7 | ISO 1206 / GB/T 309 |
| 25 | 33 | 16 | 22.8 | ISO 1206 / GB/T 309 |
| 30 | 40 | 20 | 33.0 | ISO 1206 / GB/T 309 |
| 40 | 50 | 20 | 42.5 | ISO 1206 / GB/T 309 |
Equivalent Standards
Where direct equivalents exist (ISO ↔ DIN, ISO ↔ ASME), they are listed on the parent Needle Roller Bearing — ISO / DIN (Series 133) page.
Always confirm against the dimensions on this page, since some "equivalent" standards differ in tolerances and head geometry.
When to Specify GB T 309
Choose GB T 309 for international engineering work and OEM supply where ISO standards are the contractual reference. It is the default modern specification for needle roller bearing — iso / din (series 133).
Custom manufacturing · Made to drawing
Need a bearing & bushing to this standard in a non-standard size?
Parts built to GB T 309 are already in the catalog, so a special is usually a variation on existing tooling rather than a new design — which is what keeps the cost down.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
