What To Know
- Use a certified torque tester or a calibration machine to apply a known torque to the wrench.
- The handle angle of a torque wrench should be perpendicular to the workpiece when the desired torque is reached.
- Signs of a faulty torque wrench include inaccurate readings, difficulty reaching the desired torque, or a loose or damaged click mechanism.
Torque wrenches are essential tools for tightening bolts and nuts to precise specifications. However, over time, these tools can lose their accuracy, leading to potential safety hazards or component damage. Therefore, it is crucial to regularly check the accuracy of your torque wrench to ensure reliable measurements. Here’s a comprehensive guide on how to do it:
Check the Torque Value
The first step is to verify the torque value displayed on the wrench. Use a certified torque tester or a calibration machine to apply a known torque to the wrench. Compare the reading on the wrench to the applied torque. If the difference exceeds the manufacturer’s specified tolerance, the wrench needs calibration.
Verify the Click Mechanism
Torque wrenches typically use a click mechanism to indicate when the desired torque is reached. Test the click mechanism by applying a torque slightly below the specified value. The wrench should not click. Then, slowly increase the torque until the click occurs. If the click happens before or after the specified torque, the wrench needs adjustment.
Observe the Needle Movement
Some torque wrenches use a needle indicator instead of a click mechanism. To check their accuracy, apply a known torque and observe the needle’s position. It should align with the specified torque mark on the scale. If it deviates significantly, the wrench needs calibration.
Check the Handle Angle
The handle angle of a torque wrench should be perpendicular to the workpiece when the desired torque is reached. Use a protractor or a digital inclinometer to measure the handle angle. If it deviates from 90 degrees, the wrench needs adjustment or repair.
Inspect the Wrench Condition
Before performing any accuracy checks, thoroughly inspect the torque wrench for any damage or wear. Check for loose screws, cracks, or bent components. If any issues are found, the wrench should not be used until it is repaired or replaced.
Calibration and Adjustment
If the torque wrench fails any of the accuracy checks, it needs to be calibrated or adjusted. Refer to the manufacturer’s instructions for specific calibration procedures. Most manufacturers recommend professional calibration at regular intervals to ensure maximum accuracy.
Proper Use and Storage
To maintain the accuracy of your torque wrench, follow these guidelines:
- Use the wrench only for its intended purpose and within its specified torque range.
- Store the wrench in a dry, clean environment when not in use.
- Protect the wrench from shock, vibration, or excessive heat.
Questions We Hear a Lot
Q: How often should I check my torque wrench for accuracy?
A: Check your torque wrench regularly, especially if it is used frequently or in critical applications. Refer to the manufacturer’s recommendations for specific intervals.
Q: Can I calibrate my torque wrench at home?
A: It is not recommended to calibrate a torque wrench at home unless you have the necessary equipment and expertise. Professional calibration is recommended for optimal accuracy.
Q: What are the signs of a faulty torque wrench?
A: Signs of a faulty torque wrench include inaccurate readings, difficulty reaching the desired torque, or a loose or damaged click mechanism.
