We can offer ISO 6789:2003 (withdrawn) and new ISO 6789:2017 standard calibrations
Why it’s important to calibrate torque wrenches:
Torque tools are calibrated to apply a certain amount of torque to a fastener. The amount of torque that is applied depends on the amount of force on the tool’s handle and the length of the wrench.
The handle contains an internal mechanical indicator which connects to a calibrated scale. When the indicator determines the desired torque has been reached, stop twisting the bolt.
It’s important to have your torque wrench calibrated regularly as if the wrench falls out of calibration it could provide inaccurate readings.
These inaccurate readings could be dangerous, especially in industries such as automotive where applying the wrong amount of torque to a wheel fastener could cause it to come loose, or to shear off.
Torque wrench calibration procedure:
During a calibration your torque wrench is placed horizontally into a torque loader and connected to a torque transducer. Torque is applied to the wrench in a clockwise direction by winding the wheel on the loader until the instrument clicks to indicate the instrument has reached the set value.
For beam, dial and digital torque wrenches where a value cannot be set, torque would be applied until the desired value has been reached.
The calibration is carried out over three test points (determined by the chosen ISO standard), with five repeatability readings taken at each test point. If the instrument is a pre-set torque tool, in most instances ten repeatability readings would be carried out at the one test point.
ISO defines the standards that torque tool calibrations must follow. In 2017, the 2003 standard (ISO 6789:2003) was withdrawn and replaced with the 2017 standard (ISO 6789:2017). The 2003 (withdrawn) standard is still commonly used however and is still a recognised standard.