M33 Hexagon Coupling Nuts are manufactured to DIN 6334. This page lists the controlling dimensions for the M33 size together 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.
M33 Dimensional Row (DIN 6334)
| Size | Pitch (mm) | Width across flats s (mm) | Width across corners e (mm) | Length l (mm) | Reference standard |
|---|---|---|---|---|---|
| M33 | 3.5 | 50 | 55.37 | 99 | DIN 6334 |
Spanner & Drive for M33 Hexagon Coupling Nuts
Drive geometry for M33 Hexagon Coupling Nuts is given by the row above; match the tool to the listed values.
Tightening Torque for M33
| Class 8.8 (dry, ~µ 0.125) | ≈ 1964 Nm |
|---|---|
| Class 10.9 (dry, ~µ 0.125) | ≈ 2797 Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 3273 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 M33
Nuts are graded to ISO 898-2 by the proof load the nut itself will hold (classes 04, 05, 5, 6, 8, 10 and 12), not by the 8.8 / 10.9 / 12.9 scale used for bolts. A class-8 nut is the correct mate for a class-8.8 bolt, and the joint is designed on the bolt, so no bolt-tension figure is quoted here.
Installation Tips for M33 Hexagon Coupling Nuts
- At M33 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 M33
Pair M33 with the matching M33 bolt or screw, plus a M33 flat washer where required to distribute load on softer materials.
Custom manufacturing · Made to drawing
Need hexagon coupling nuts in a size this table does not list?
This page covers M33 hexagon coupling nuts. Thread size is the obvious variable and rarely the interesting one — height for clearance, across-flats for the tool already in the cell, and the locking feature for the vibration actually present. Made by cold heading or tapping.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
