The M36 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.
M36 Dimensional Row (DIN 6334)
| Size | Pitch (mm) | Width across flats s (mm) | Width across corners e (mm) | Length l (mm) | Reference standard |
|---|---|---|---|---|---|
| M36 | 4.0 | 55 | 60.79 | 108 | DIN 6334 |
Spanner & Drive for M36 Hexagon Coupling Nuts
Drive geometry for M36 Hexagon Coupling Nuts is given by the row above; match the tool to the listed values.
Tightening Torque for M36
| Class 8.8 (dry, ~µ 0.125) | ≈ 2450 Nm |
|---|---|
| Class 10.9 (dry, ~µ 0.125) | ≈ 3450 Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 4150 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 M36
| Tensile stress area As (ISO 898-1) | 817 mm² |
|---|---|
| Proof load, class 8.8 | 490 kN |
| Proof load, class 10.9 | 678 kN |
| Proof load, class 12.9 | 792 kN |
| Min. ultimate tensile, class 8.8 | 654 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 M36 Hexagon Coupling Nuts
M36 Hexagon Coupling Nuts are commonly specified for structural joints, flange connections and heavy equipment foundations.
Installation Tips for M36 Hexagon Coupling Nuts
- At M36 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 M36
Pair M36 with the matching M36 bolt or screw, plus a M36 flat washer where required to distribute load on softer materials.

