Dimensional and assembly data for M24 Swing Bolt to GB/T 77 / ISO 4026. 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.
M24 Dimensional Row (GB/T 77 / ISO 4026)
| Thread size | Pitch (mm) | Ring outer dia D (mm) | Ring wire dia (mm) | Total length L (mm) | SWL (kg, axial) | Reference standard |
|---|---|---|---|---|---|---|
| M24 | 3.0 | 50 | 20 | 90 | 1800 | DIN 580 / GB/T 825 |
Spanner & Drive for M24 Swing Bolt — GB/T 77 / ISO 4026 (Series 020)
Drive geometry for M24 Swing Bolt — GB/T 77 / ISO 4026 (Series 020) is given by the row above; match the tool to the listed values.
Hole Sizes for M24
| Coarse-thread pitch (ISO 724) | 3 mm |
|---|---|
| Through-hole / clearance (ISO 273 medium) | 26 mm |
| Tapping drill, coarse thread | 21 mm |
Tightening Torque for M24
| Class 8.8 (dry, ~µ 0.125) | ≈ 710 Nm |
|---|---|
| Class 10.9 (dry, ~µ 0.125) | ≈ 1000 Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 1200 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
| Tensile stress area As (ISO 898-1) | 353 mm² |
|---|---|
| Proof load, class 8.8 | 212 kN |
| Proof load, class 10.9 | 293 kN |
| Proof load, class 12.9 | 342 kN |
| Min. ultimate tensile, class 8.8 | 282 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.
M24 Swing Bolt — GB/T 77 / ISO 4026 (Series 020) Weight
A steel M24 swing bolt at the listed 90 mm length weighs approximately 320 g each — about 320 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 M24 Swing Bolt — GB/T 77 / ISO 4026 (Series 020)
M24 Swing Bolt — GB/T 77 / ISO 4026 (Series 020) are commonly specified for structural steelwork, heavy machinery foundations and large flange joints.
Installation Tips for M24 Swing Bolt — GB/T 77 / ISO 4026 (Series 020)
- 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
For M24, pair with a M24 hex nut (ISO 4032 / DIN 934) and, where used, a M24 flat washer (ISO 7089 / DIN 125A) under the head and under the nut.