Selecting Wedge / Taper Washer — GB/T 852 (Series 084), M4, in GB/T 852: the dimensional row from the standard plus the tools and hole sizes follow. Use them with the technical drawing below — the drawing redraws to the exact size you pick.
M4 Dimensional Row (GB/T 852)
| For bolt size | Inner diameter d1 (mm) | Outer diameter d2 (mm) | Mean thickness t (mm) | Slope | Reference standard |
|---|---|---|---|---|---|
| M4 | 4.5 | 8 | 1.6 | 1:6 | DIN 6917 / GB/T 853 |
Spanner & Drive for M4 Wedge / Taper Washer — GB/T 852 (Series 084)
Drive geometry for M4 Wedge / Taper Washer — GB/T 852 (Series 084) is given by the row above; match the tool to the listed values.
Common Applications for M4 Wedge / Taper Washer — GB/T 852 (Series 084)
M4 Wedge / Taper Washer — GB/T 852 (Series 084) are commonly specified for small electronics hardware and precision assemblies.
Installation Tips for M4 Wedge / Taper Washer — GB/T 852 (Series 084)
- At M4 the joint is sensitive to over-torque — use a torque-limiting driver and check the head doesn't bury into a softer counterpart.
Mating Parts for M4
A M4 flat washer pairs with a M4 bolt/screw and matching M4 nut.
When to Step Up or Down from M4
When the joint preload approaches the proof load of M4 class 8.8, step up to M5 class 8.8 (or move to M4 class 10.9). When the joint is over-specified, M3 often saves weight and cost without losing the safety margin.