On the bench specifying M16 Hex Flange Nuts? This page gives the controlling dimensions for the M16 size of Hex Flange Nuts (to ISO 4161 / DIN 6923).
M16 Dimensional Row (ISO 4161 / DIN 6923)
| Size | Pitch (mm) | Flange diameter dc (mm) | Nut height m (mm) | Width across flats s (mm) | Reference standard |
|---|---|---|---|---|---|
| M16 | 2.0 | 34.5 | 16.0 | 24.0 | ISO 4161 / DIN 6923 |
Spanner & Drive for M16 Hex Flange Nuts
M16 Hex Flange Nuts have a width across flats of 24.0 mm — fit a 24.0 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 M16 Hex Flange Nuts
M16 Hex Flange Nuts are commonly specified for medium-duty structural joints and motor / chassis mounting.
Installation Tips for M16 Hex Flange Nuts
- 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.
Mating Parts for M16
Pair M16 with the matching M16 bolt or screw, plus a M16 flat washer where required to distribute load on softer materials.
When to Step Up or Down from M16
When the joint preload approaches the proof load of M16 class 8.8, step up to M20 class 8.8 (or move to M16 class 10.9). When the joint is over-specified, M12 often saves weight and cost without losing the safety margin.