Dimensional data for M14 Hex Nut to GB/T 41 / ISO 4034, with the drive and the installation notes for this type. Values are taken from the governing standard rather than from a general machine-thread table, because this type is not selected on one.
M14 Dimensional Row (GB/T 41 / ISO 4034)
| Size | Pitch (mm) | Width across flats s (mm) | Width across corners e (mm) | Nut height m (mm) | Reference standard |
|---|---|---|---|---|---|
| M14 | 2.0 | 21.0 | 23.36 | 12.8 | ISO 4032 / GB/T 6170 |
Spanner & Drive for M14 Hex Nut — GB/T 41 / ISO 4034 (Series 060)
M14 Hex Nut — GB/T 41 / ISO 4034 (Series 060) have a width across flats of 21.0 mm — fit a 21.0 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.
Tightening Torque for M14
| Class 8.8 (dry, ~µ 0.125) | ≈ 135 Nm |
|---|---|
| Class 10.9 (dry, ~µ 0.125) | ≈ 190 Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 230 Nm |
Indicative dry-joint values. Lubrication can lower the required torque by 15–25%. Always confirm against the joint design, especially when going up a strength class.
Proof Load & Strength for M14
| Tensile stress area As (ISO 898-1) | 115 mm² |
|---|---|
| Proof load, class 8.8 | 67 kN |
| Proof load, class 10.9 | 95 kN |
| Proof load, class 12.9 | 112 kN |
| Min. ultimate tensile, class 8.8 | 92 kN |
Proof load = stress area × proof stress per ISO 898-1. Design joints so the working preload stays below the proof load of the selected class.
Common Applications for M14 Hex Nut — GB/T 41 / ISO 4034 (Series 060)
M14 Hex Nut — GB/T 41 / ISO 4034 (Series 060) are commonly specified for medium-duty structural joints and motor / chassis mounting.
Installation Tips for M14 Hex Nut — GB/T 41 / ISO 4034 (Series 060)
- 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 M14
Pair M14 with the matching M14 bolt or screw, plus a M14 flat washer where required to distribute load on softer materials.

