The M36 size of Socket Head Cap Screw is dimensioned by GB/T 5281 / ISO 7379. The tables below give the dimensional row from the standard, the drill and spanner sizes that go with it, and the assembly torque per property class. The technical drawing on this page redraws to the exact values selected.
M36 Dimensional Row (GB/T 5281 / ISO 7379)
| Size | Pitch (mm) | Length L (mm) | Head diameter dk (mm) | Head height k (mm) | Hex socket s (mm) | Reference standard |
|---|---|---|---|---|---|---|
| M36 | 4.0 | 200 | 54.0 | 36 | 27.0 | ISO 4762 / GB/T 70.1 |
Spanner & Drive for M36 Socket Head Cap Screw — GB/T 5281 / ISO 7379 (Series 016)
The hex socket for M36 Socket Head Cap Screw — GB/T 5281 / ISO 7379 (Series 016) 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.
Hole Sizes for M36
| Coarse-thread pitch (ISO 724) | 4 mm |
|---|---|
| Through-hole / clearance (ISO 273 medium) | 39 mm |
| Tapping drill, coarse thread | 32 mm |
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.
M36 Socket Head Cap Screw — GB/T 5281 / ISO 7379 (Series 016) Weight
A steel M36 socket head cap screw at the listed 200 mm length weighs approximately 3,596 g each — about 3,596 kg per 1,000 pieces. Stainless A2/A4 weighs roughly the same (density 7.9–8.0 g/cm³). Actual weight varies slightly with head form, thread and finish; use this figure for freight estimation only.
Common Applications for M36 Socket Head Cap Screw — GB/T 5281 / ISO 7379 (Series 016)
M36 Socket Head Cap Screw — GB/T 5281 / ISO 7379 (Series 016) are commonly specified for heavy assembly and large machine mounts.
Installation Tips for M36 Socket Head Cap Screw — GB/T 5281 / ISO 7379 (Series 016)
- 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 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
For M36, pair with a M36 hex nut (ISO 4032 / DIN 934) and, where used, a M36 flat washer (ISO 7089 / DIN 125A) under the head and under the nut.