What is the purpose of a torque wrench and what should be done before use?

• A. To measure torque only; ensure it is calibrated and zeroed before use.
• B. To vibrate the joint.
• C. To apply a specified torque; ensure it is calibrated and zeroed before use.
• D. To cut threads.

Answer: (C)

A torque wrench is used to apply a specific, controlled torque to a fastener, ensuring the right clamping force so joints are neither under- nor over-tightened. Before you use it, confirm that the tool is calibrated to the required tolerance and set to zero (or to the correct torque value) so that the wrench delivers the exact amount of torque when tightened. This calibration and zeroing ensure accuracy and consistency with maintenance data. The purpose isn’t to vibrate the joint or cut threads, and it’s not simply a device to measure torque during tightening; it’s designed to apply the precise torque specified.