How to Torque a Bolt Correctly
- Clean and lightly lubricate the threads unless the spec assumes dry assembly.
- Snug the joint by hand, then tighten in a crossing pattern for multi-bolt flanges.
- Set the torque wrench to the specified value for the size and grade.
- Tighten smoothly to the click or indicator — do not jerk or re-click.
- Re-check in sequence after a short settling period on critical joints.
- Never reuse a stretched or necked bolt.