Overview
Engineering reference data for Metric Bolts Maximum Torque in mechanics.
Key Formulas
Newton's Second Law
Force = mass × acceleration.
Work
Work = force × displacement × cos(angle).
Kinetic Energy
Energy of motion.
Potential Energy
Gravitational potential energy.
Variables
| Symbol | Description | Unit |
|---|---|---|
| Force | N | |
| Mass | kg | |
| Acceleration | m/s² | |
| Velocity | m/s |
Application Conditions
The torque values in the table below are based on the following conditions:
- Thread type: Coarse threaded bolts
- Surface condition: Lightly oiled threads
- Tension: 85% of proof load
These conditions represent typical industrial applications. Torque values should be adjusted when using different lubricants, surface coatings, or target preload percentages.
Maximum Tightening Torques
Property Class Grades
Metric bolt property classes indicate the bolt's mechanical strength:
| Grade | Tensile Strength (MPa) | Yield Strength (MPa) | Common Applications |
|---|---|---|---|
| 8.8 | 800 | 640 | General purpose structural |
| 9.8 | 900 | 720 | Higher strength applications |
| 10.9 | 1040 | 940 | High-strength, automotive |
| 12.9 | 1220 | 1100 | Maximum strength, critical joints |
Note: Always verify torque specifications with the fastener manufacturer for critical applications, as actual values may vary based on thread tolerance, joint stiffness, and other factors.