The M24 size of Thin Hex Nut, Fine Pitch is dimensioned by GB/T 6173 / ISO 8675. The table below gives the dimensional row from the standard, followed by 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.
M24 Dimensional Row (GB/T 6173 / ISO 8675)
| Size | Pitch (mm) | Width across flats s (mm) | Width across corners e (mm) | Nut height m (mm) | Reference standard |
|---|---|---|---|---|---|
| M24 | 3.0 | 36.0 | 39.98 | 12.0 | ISO 4035 / GB/T 6172 |
Spanner & Drive for M24 Thin Hex Nut, Fine Pitch — GB/T 6173 / ISO 8675 (Series 056)
M24 Thin Hex Nut, Fine Pitch — GB/T 6173 / ISO 8675 (Series 056) have a width across flats of 36.0 mm — fit a 36.0 mm open-ended spanner or socket. In tight access a 6-point socket on the 36.0 mm flats gives the most engagement per degree of swing. Where the joint is torqued to a figure, a click wrench is the only way to reproduce it across a batch.
Tightening Torque for M24
| Class 8.8 (dry, ~µ 0.125) | ≈ 726 Nm |
|---|---|
| Class 10.9 (dry, ~µ 0.125) | ≈ 1034 Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 1210 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 M24
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 M24 Thin Hex Nut, Fine Pitch — GB/T 6173 / ISO 8675 (Series 056)
- Use a 6-point socket where access allows — 12-point sockets are more prone to rounding the corners on smaller sizes.
- Serrated flanges need to sit directly on the joint face. A washer between the two removes the bite and leaves an ordinary bolted joint that is believed to be a locking one.
- At M24 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 M24
Pair M24 with the matching M24 bolt or screw, plus a M24 flat washer where required to distribute load on softer materials.
Custom manufacturing · Made to drawing
Need thin hex nut, fine pitch in a size this table does not list?
This page covers M24 thin hex nut, fine pitch. Thread, height, across-flats, property class, locking feature and flange form can all be varied, including thread sizes the standard series does not run to. Made by cold heading or tapping.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.

