For Internally Threaded Dowel Pin — GB/T 120.1 / ISO 8735 (Series 100), GB defines dimensions, tolerances and product grades. The sections below describe its scope, what it does NOT cover, and the equivalents across DIN, ISO and ASME.
GB — Scope
GB specifies the dimensions and tolerances of internally threaded dowel pin — gb/t 120.1 / iso 8735 (series 100). Material, property class, surface finish and packaging are governed by separate documents in the same standards family (for example ISO 898-1 for the mechanical property classes of bolts and screws).
Tolerance & Product Grades
GB, alongside the related GB/T 120.1 / ISO 8735 entries on this site, specifies product grades (typically A or B for fine work and C for general engineering) and tolerance classes for the controlling dimensions. Choose the grade against the precision your application requires.
Dimensions Specified by GB
| Nominal diameter d (mm) | Length L (mm) | Internal thread | Material | Reference standard |
|---|---|---|---|---|
| 4 | 16 | M3 | Alloy steel | ISO 8736 / GB/T 120 |
| 5 | 20 | M4 | Alloy steel | ISO 8736 / GB/T 120 |
| 6 | 24 | M4 | Alloy steel | ISO 8736 / GB/T 120 |
| 8 | 30 | M5 | Alloy steel | ISO 8736 / GB/T 120 |
| 10 | 40 | M6 | Alloy steel | ISO 8736 / GB/T 120 |
| 12 | 50 | M8 | Alloy steel | ISO 8736 / GB/T 120 |
| 16 | 60 | M10 | Alloy steel | ISO 8736 / GB/T 120 |
| 20 | 80 | M12 | Alloy steel | ISO 8736 / GB/T 120 |
Equivalent Standards
Where direct equivalents exist (ISO ↔ DIN, ISO ↔ ASME), they are listed on the parent Internally Threaded Dowel Pin — GB/T 120.1 / ISO 8735 (Series 100) page. Always confirm against the dimensions on this page, since some "equivalent" standards differ in tolerances and head geometry.
When to Specify GB
Choose GB for international engineering work and OEM supply where ISO standards are the contractual reference. It is the default modern specification for internally threaded dowel pin — gb/t 120.1 / iso 8735 (series 100).