Selecting Threaded Rod — GB/T 15389 / DIN 939 (Series 095), M8, in GB/T 15389 / DIN 939: the dimensional row from the standard plus the tools and hole sizes follow. Use them with the technical drawing below — the drawing redraws to the exact size you pick.
M8 Dimensional Row (GB/T 15389 / DIN 939)
| Thread size | Pitch (mm) | Length L (mm) | Engagement depth bm (mm) | Material | Reference standard |
|---|---|---|---|---|---|
| M8 | 1.25 | 60 | 10 | Cl. 8.8 alloy steel | DIN 939 / GB/T 901 |
Spanner & Drive for M8 Threaded Rod — GB/T 15389 / DIN 939 (Series 095)
Drive geometry for M8 Threaded Rod — GB/T 15389 / DIN 939 (Series 095) is given by the row above; match the tool to the listed values.
Hole Sizes for M8
| Coarse-thread pitch (ISO 724) | 1.25 mm |
|---|---|
| Through-hole / clearance (ISO 273 medium) | 9 mm |
| Tapping drill, coarse thread | 6.8 mm |
Tightening Torque for M8
| Class 8.8 (dry, ~µ 0.125) | ≈ 25 Nm |
|---|---|
| Class 10.9 (dry, ~µ 0.125) | ≈ 35 Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 41 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.
Common Applications for M8 Threaded Rod — GB/T 15389 / DIN 939 (Series 095)
M8 Threaded Rod — GB/T 15389 / DIN 939 (Series 095) are commonly specified for general-purpose machinery, jigs, fixturing and light structural connections.
Mating Parts for M8
For M8, pair with a M8 hex nut (ISO 4032 / DIN 934) and, where used, a M8 flat washer (ISO 7089 / DIN 125A) under the head and under the nut.
When to Step Up or Down from M8
When the joint preload approaches the proof load of M8 class 8.8, step up to M10 class 8.8 (or move to M8 class 10.9). When the joint is over-specified, M6 often saves weight and cost without losing the safety margin.