Dimensional and assembly data for M33 Socket Head Cap Screws to ISO 4762 / DIN 912. Includes head size and width across flats, clearance-hole and tapping-drill diameters, tightening torque per property class, and the sizes to step up or down to when the joint requires it.
M33 Dimensional Row (ISO 4762 / DIN 912)
| Size | Pitch (mm) | Head diameter dk (mm) | Head height k (mm) | Hex key s (mm) | Socket depth t min (mm) | Reference standard |
|---|---|---|---|---|---|---|
| M33 | 3.5 | 50.0 | 33.0 | 24.0 | 17.5 | ISO 4762 / DIN 912 |
Spanner & Drive for M33 Socket Head Cap Screws
The hex socket for M33 Socket Head Cap Screws is shown in the spec table — use the matching Allen / hex key (an ISO 2936 hex key set covers the full range). A T-handle Allen key gives the best feel for setting preload by feel; for production work use a torque-controlled driver.
Common Applications for M33 Socket Head Cap Screws
M33 Socket Head Cap Screws are commonly specified for heavy assembly and large machine mounts.
Installation Tips for M33 Socket Head Cap Screws
- Use a quality Allen key fully seated in the socket — partial engagement is the most common cause of stripped sockets at this size.
- For countersunk and button-head variants, chamfer the through-hole to seat the head flush without preloading the head/shank fillet.
- 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
For M33, pair with a M33 hex nut (ISO 4032 / DIN 934) and, where used, a M33 flat washer (ISO 7089 / DIN 125A) under the head and under the nut.
