The M12 size of Hex Thick Nut is dimensioned by DIN 6330 / GB/T 56. The tables below give the dimensional row from the standard, the drill and spanner sizes that go with it, and the assembly torque per property class. The technical drawing on this page redraws to the exact values selected.
M12 Dimensional Row (DIN 6330 / GB/T 56)
| Size | Pitch (mm) | Width across flats s (mm) | Width across corners e (mm) | Nut height m (mm) | Reference standard |
|---|---|---|---|---|---|
| M12 | 1.75 | 18.0 | 20.03 | 10.8 | ISO 4032 / GB/T 6170 |
Spanner & Drive for M12 Hex Thick Nut — DIN 6330 / GB/T 56 (Series 052)
M12 Hex Thick Nut — DIN 6330 / GB/T 56 (Series 052) have a width across flats of 18.0 mm — fit a 18.0 mm open-ended spanner or socket. Use a 6-point socket for tight clearances and to reduce rounding; for repeated assembly choose a torque wrench so the joint preload is repeatable.
Common Applications for M12 Hex Thick Nut — DIN 6330 / GB/T 56 (Series 052)
M12 Hex Thick Nut — DIN 6330 / GB/T 56 (Series 052) are commonly specified for medium-duty structural joints and motor / chassis mounting.
Installation Tips for M12 Hex Thick Nut — DIN 6330 / GB/T 56 (Series 052)
- Use a 6-point socket where access allows — 12-point sockets are more prone to rounding the corners on smaller sizes.
- On flanged or serrated variants, do NOT add a separate flat washer — the flange already spreads the load and the washer can defeat the locking serrations.
When to Step Up or Down from M12
When the joint preload approaches the proof load of M12 class 8.8, step up to M16 class 8.8 (or move to M12 class 10.9). When the joint is over-specified, M10 often saves weight and cost without losing the safety margin.