The M14 size of Hexagon Coupling Nuts is dimensioned by DIN 6334. The table below gives the dimensional row from the standard, followed by the drive and the installation notes for this type.
M14 Dimensional Row (DIN 6334)
| Size | Pitch (mm) | Width across flats s (mm) | Width across corners e (mm) | Length l (mm) | Reference standard |
|---|---|---|---|---|---|
| M14 | 2.0 | 22 | 24.49 | 42 | DIN 6334 |
Spanner & Drive for M14 Hexagon Coupling Nuts
Drive geometry for M14 Hexagon Coupling Nuts is given by the row above; match the tool to the listed values.
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 Hexagon Coupling Nuts
M14 Hexagon Coupling Nuts are commonly specified for medium-duty structural joints and motor / chassis mounting.
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.

