For Sheet-Metal Self-Tapping Screw — GB/T 845 / ISO 7049 (Series 045), ISO 7049 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.
ISO 7049 — Scope
ISO 7049 specifies the dimensions and tolerances of sheet-metal self-tapping screw — gb/t 845 / iso 7049 (series 045). 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
ISO 7049, alongside the related GB/T 845 / ISO 7049 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 ISO 7049
| Size | Nominal diameter (mm) | Pitch (mm) | Length L (mm) | Head diameter dk (mm) | Head height k (mm) | Reference standard |
|---|---|---|---|---|---|---|
| ST2.2 | 2.2 | 0.8 | 9.5 | 4.2 | 1.4 | ISO 1481 / GB/T 845 |
| ST2.9 | 2.9 | 1.1 | 13 | 5.6 | 1.7 | ISO 1481 / GB/T 845 |
| ST3.5 | 3.5 | 1.3 | 16 | 6.9 | 2.1 | ISO 1481 / GB/T 845 |
| ST3.9 | 3.9 | 1.3 | 16 | 7.5 | 2.3 | ISO 1481 / GB/T 845 |
| ST4.2 | 4.2 | 1.4 | 19 | 8.2 | 2.5 | ISO 1481 / GB/T 845 |
| ST4.8 | 4.8 | 1.6 | 25 | 9.5 | 2.9 | ISO 1481 / GB/T 845 |
| ST5.5 | 5.5 | 1.8 | 32 | 10.9 | 3.3 | ISO 1481 / GB/T 845 |
| ST6.3 | 6.3 | 1.8 | 38 | 12.5 | 3.8 | ISO 1481 / GB/T 845 |
Equivalent Standards
Where direct equivalents exist (ISO ↔ DIN, ISO ↔ ASME), they are listed on the parent Sheet-Metal Self-Tapping Screw — GB/T 845 / ISO 7049 (Series 045) page. Always confirm against the dimensions on this page, since some "equivalent" standards differ in tolerances and head geometry.
When to Specify ISO 7049
Choose ISO 7049 for international engineering work and OEM supply where ISO standards are the contractual reference. It is the default modern specification for sheet-metal self-tapping screw — gb/t 845 / iso 7049 (series 045).