This page covers M30 Tab Lock Washer for Round Nut to GB/T 858: the full dimensional row, hole and tool sizes, proof-load data and typical applications. All values are taken from the governing standards (GB/T 858 together with ISO 273, ISO 724 and ISO 898-1 where applicable).
M30 Dimensional Row (GB/T 858)
| For shaft / nut size | Inner diameter d1 (mm) | Outer diameter d2 (mm) | Thickness t (mm) | Tab length (mm) | Reference standard |
|---|---|---|---|---|---|
| M30 | 30.5 | 55 | 1.5 | 16 | GB/T 858 |
Spanner & Drive for M30 Tab Lock Washer for Round Nut — GB/T 858 (Series 089)
Drive geometry for M30 Tab Lock Washer for Round Nut — GB/T 858 (Series 089) is given by the row above; match the tool to the listed values.
Common Applications for M30 Tab Lock Washer for Round Nut — GB/T 858 (Series 089)
M30 Tab Lock Washer for Round Nut — GB/T 858 (Series 089) are commonly specified for high-load load-spreading on structural joints.
Installation Tips for M30 Tab Lock Washer for Round Nut — GB/T 858 (Series 089)
- At M30 the stretch in the bolt becomes the controlling factor — for critical joints, use angle-controlled or stretch-controlled tightening instead of pure torque.
Mating Parts for M30
A M30 flat washer pairs with a M30 bolt/screw and matching M30 nut.

