A torque wrench is a tool used to measure the tightening force applied to nuts and bolts. It assists in making sure they are not too tight or too loose. For that, one needs to maintain a balance between strength and flexibility. This instrument appears like a long-armed wrench. It bends as you turn the handle and exert a turning force on it. Its handle holds inside a mechanical indicator that links to a calibrated scale.
It would be best to stop twisting the bolt when the indicator shows you have reached the desired torque. Like other measuring devices, torque wrench calibration is vital for delivering outcomes.
Torque Wrench Calibration and Testing
Measure the distance from the square drive to the handle. The square drive is where you would connect a socket, and for ease, we will use whole inches instead of fractions. Label the point on the handle you have measured, marking a distance on a piece of paper for future reference.
Set the paper aside in a safe space until you need it.
Since 24 inches (61 cm) is a typical length for many torque wrenches, use it as the measurement.
Put the square drive in the vice. Arrange your bench vice so that you can put it in the square drive of the torque wrench with the handle sticking out. Next, insert this square drive into the vice and make it fully tight.
Watch out for overtightening the vice, as it might harm the square drive on your torque wrench.
Confirm that the clamp only catches the square drive on its own. This lets the wrench shift beneath the load you put on it.
Calculate the appropriate setting for your weight.
The equation is: handle distance times weight, divided by 12. To find out the right setting for the wrench, multiply the distance you measured in step 2 by 20 pounds. This will be what you are going to use as a weight. That should give us an answer of 480-inch pounds (24 inches multiplied by 20 pounds). It ultimately equates to 40-foot pounds (480-inch pounds divided by 12).
If you are using metric units, first convert the weight to Newtons. You do this by multiplying the number of kilograms by 9.807. For instance, 9.07 kg x 9.807 = 88.94949 Newtons in this example. Next, you take the number of Newtons and multiply it by the length in meters. Here’s how you can do it: 88.94949 Newtons x 0.6096 metres = 54.2 Newton metres.
Multiply by 1.35582 to convert foot pounds to Newton meters. For example, 40 foot-pounds are equal to 54.2 Newton metres.
Make certain to use the proper distance and weight numbers. If your wrench is of a different size or you are utilising diverse weights, the figures will be distinct.
Hang the weights from the handle of the wrench.
Attach the rope to the weight and create a loop. This loop can then be hung from the handle of your torque wrench at the spot where you marked it.
- Ensure that the length of the rope is not too long so that, when hung, its weight does not touch the ground.
- Do not securely tie the weight to the wrench. Instead, simply hang it.
- Make sure there is no obstruction or help for the weight when it is suspended.
Final Thoughts
To skilfully use a torque wrench, pay attention and adhere to best practices for safety. With our comprehensive guide, enhance your torque wrench’s task quality and lifespan/accuracy. Be it an expert or a beginner in torque applications, follow these steps in your routine. It will ensure that you use the torque wrench as a reliable instrument for tasks.