ISO 7046 is the governing dimensional standard for phillips countersunk machine screw. This page sets out the scope of the standard, reproduces the full size table it specifies, and lists the DIN/ISO/ASME cross-references commonly cited in datasheets and drawings.
ISO 7046 — Scope
ISO 7046 specifies the dimensions and tolerances of phillips countersunk machine screw — gb/t 819.1 / iso 7046 (series 030). 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 7046, alongside the related GB/T 819.1 / ISO 7046 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 7046
| Size | Pitch (mm) | Length L (mm) | Head diameter dk (mm) | Head height k (mm) | Cross recess | Countersink angle (deg) | Reference standard |
|---|---|---|---|---|---|---|---|
| M3 | 0.5 | 20 | 5.6 | 1.65 | PH1 | 90 | ISO 7046 / GB/T 819 |
| M4 | 0.7 | 25 | 7.5 | 2.2 | PH2 | 90 | ISO 7046 / GB/T 819 |
| M5 | 0.8 | 30 | 9.2 | 2.5 | PH2 | 90 | ISO 7046 / GB/T 819 |
| M6 | 1.0 | 40 | 11.0 | 3.0 | PH3 | 90 | ISO 7046 / GB/T 819 |
| M8 | 1.25 | 50 | 14.5 | 4.0 | PH3 | 90 | ISO 7046 / GB/T 819 |
| M10 | 1.5 | 60 | 18.0 | 5.0 | PH4 | 90 | ISO 7046 / GB/T 819 |
| M12 | 1.75 | 80 | 22.0 | 6.0 | PH4 | 90 | ISO 7046 / GB/T 819 |
| M14 | 2.0 | 80 | 25.0 | 7.0 | PH4 | 90 | ISO 7046 / GB/T 819 |
| M16 | 2.0 | 100 | 29.0 | 8.0 | PH4 | 90 | ISO 7046 / GB/T 819 |
| M18 | 2.5 | 100 | 33.0 | 9.0 | PH4 | 90 | ISO 7046 / GB/T 819 |
| M20 | 2.5 | 120 | 36.5 | 10.0 | PH4 | 90 | ISO 7046 / GB/T 819 |
| M24 | 3.0 | 150 | 43.5 | 12.0 | PH4 | 90 | ISO 7046 / GB/T 819 |
Companion Standards
ISO 7046 controls only the geometry of phillips countersunk machine screw — gb/t 819.1 / iso 7046 (series 030). The mechanical strength is set by ISO 898-1 (bolts and screws) or ISO 898-2 (nuts); the surface finish is governed by separate finish standards (e.g. ISO 4042 for electroplating). For corrosion testing, the relevant document is ISO 9227 (neutral salt spray).
When to Specify ISO 7046
Choose ISO 7046 for international engineering work and OEM supply where ISO standards are the contractual reference. It is the default modern specification for phillips countersunk machine screw — gb/t 819.1 / iso 7046 (series 030).