03.11.2024

Torque wrench checking, adjustment and calibration

Mechanical torque wrench is checked on the test device.
Torque wrenches are measuring tools. The technology inside ensures that a trigger signal can be heard, seen or felt when the target value is reached. To ensure consistently accurate and reliable results, the torque wrench must be tested regularly - as standard after one year at the latest, ideally even more frequently. We will explain what is required and when.
01.

Check the torque wrench

Torque or angle-controlled torque wrench testing determines whether the tool operates reliably within a specified tolerance range. This is important to ensure consistently high quality and to rule out faulty bolted connections. A special test device is required for such a test, which is why an external test is usually chosen. However, companies are increasingly investing in their own testing equipment - because this enables them to check their torque wrenches every day before the start of a shift, for example. Important: Regular testing is not mandatory, it is done voluntarily or in a company's own interest, e.g. to reduce economic risks.
Learn more about testing here: Maximum safety: Measuring equipment testing
02.

Torque wrench adjustment

If this test reveals that the torque wrench no longer operates within the tolerance, adjustment of the mechanics can often bring it back into the tolerance range. It usually needs to be dismantled for this operation, which is why the adjustment is often entrusted to a service provider. This is not necessary with a mechanical torque wrench from STAHLWILLE, as the screws responsible for the adjustment can be reached without disassembly. This allows you to adjust the tool yourself.
03.

Torque wrench calibration

During calibration, a torque wrench is returned to the national or international “normal”. For this purpose, its measurement results are compared with those of a reference measuring instrument that is at least 4 times more accurate. Regular calibration is mandatory for all companies that are certified according to the DIN EN ISO 9001 industry standard, for example, and use torque tools. The length of the calibration intervals is determined by the company itself. Anyone who works in accordance with DIN EN ISO 6789 must have their torque wrenches calibrated after twelve months or 5,000 loads at the latest, unless different intervals have been specified. Calibration is usually performed in accredited calibration laboratories. As this is associated with higher costs compared to testing, a growing number of companies are relying on their own calibration facilities to reduce tool costs and increase tool availability.
Learn more about calibration here: Maximum efficiency: Calibration technology