M16 is one of the standard coarse-thread sizes for equal-end stud bolt under GB/T 901 / DIN 939. The sections below reproduce the dimensional row, list the matching tools and hole sizes, and summarize where this size is normally specified.
M16 Dimensional Row (GB/T 901 / DIN 939)
| Thread size | Pitch (mm) | Length L (mm) | Engagement depth bm (mm) | Material | Reference standard |
|---|---|---|---|---|---|
| M16 | 2.0 | 150 | 24 | Cl. 8.8 alloy steel | DIN 939 / GB/T 901 |
Hole Sizes for M16
| Coarse-thread pitch (ISO 724) | 2 mm |
|---|---|
| Through-hole / clearance (ISO 273 medium) | 17.5 mm |
| Tapping drill, coarse thread | 14 mm |
Tightening Torque for M16
| Class 8.8 (dry, ~µ 0.125) | ≈ 210 Nm |
|---|---|
| Class 10.9 (dry, ~µ 0.125) | ≈ 295 Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 355 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 M16
| Tensile stress area As (ISO 898-1) | 157 mm² |
|---|---|
| Proof load, class 8.8 | 91 kN |
| Proof load, class 10.9 | 130 kN |
| Proof load, class 12.9 | 152 kN |
| Min. ultimate tensile, class 8.8 | 126 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.
Common Applications for M16 Equal-End Stud Bolt — GB/T 901 / DIN 939 (Series 093)
M16 Equal-End Stud Bolt — GB/T 901 / DIN 939 (Series 093) are commonly specified for medium-duty structural connections, automotive sub-frames and equipment chassis.
Mating Parts for M16
For M16, pair with a M16 hex nut (ISO 4032 / DIN 934) and, where used, a M16 flat washer (ISO 7089 / DIN 125A) under the head and under the nut.
When to Step Up or Down from M16
When the joint preload approaches the proof load of M16 class 8.8, step up to M20 class 8.8 (or move to M16 class 10.9). When the joint is over-specified, M12 often saves weight and cost without losing the safety margin.
