Dimensional and assembly data for M20 Spring Lock Washer to GB/T 93 / DIN 127B. Includes head size and width across flats, clearance-hole and tapping-drill diameters, tightening torque per property class, and the sizes to step up or down to when the joint requires it.
M20 Dimensional Row (GB/T 93 / DIN 127B)
| For bolt size | Inner diameter d1 (mm) | Outer diameter d2 (mm) | Width b (mm) | Thickness t (mm) | Reference standard |
|---|---|---|---|---|---|
| M20 | 20.2 | 33.6 | 5.5 | 5.0 | GB/T 93 / DIN 127B |
Spanner & Drive for M20 Spring Lock Washer — GB/T 93 / DIN 127B (Series 080)
Drive geometry for M20 Spring Lock Washer — GB/T 93 / DIN 127B (Series 080) is given by the row above; match the tool to the listed values.
Common Applications for M20 Spring Lock Washer — GB/T 93 / DIN 127B (Series 080)
M20 Spring Lock Washer — GB/T 93 / DIN 127B (Series 080) are commonly specified for high-load load-spreading on structural joints.
Installation Tips for M20 Spring Lock Washer — GB/T 93 / DIN 127B (Series 080)
- At M20 the stretch in the bolt becomes the controlling factor — for critical joints, use angle-controlled or stretch-controlled tightening instead of pure torque.
When to Step Up or Down from M20
When the joint preload approaches the proof load of M20 class 8.8, step up to M24 class 8.8 (or move to M20 class 10.9). When the joint is over-specified, M16 often saves weight and cost without losing the safety margin.