How to Use a Torque Wrench 1

1. How to Use a Torque Wrench？

A torque wrench is a hand-held wrench that is used to tighten a fastener – such as a bolt or a nut – to the specified torque. Torque wrenches are indispensable for many repairs and wheel changes on vehicles of all kinds. They are also used for industrial maintenance and repair work, especially when the safety of life and limb is at stake.

If screw connections have to be loosened and tightened again for the maintenance of an automobile, this must be done taking into account the torques specified by the manufacturer. This applies in particular to wheels and too many other bolted parts such as the cylinder head. Please note that the required torques are different for each type of vehicle.

A torque wrench is an assembly tool. It is a sensitive and precise tool for tightening screws and nuts and should not be used to loosen them.

1. Treat your torque wrench as carefully as you would a measuring instrument. The tool should always be kept protected in a box and protected from bumps.

2. At the end of a working day or when not in use, the torque wrench should be reset to the lowest possible value to release the spring tension.

3. Use only one hand with fluid and continuous movement. Most torque wrenches have a mark on the handle that shows where to apply pressure.

4. Work with only one hand and pull in one fluid, continuous motion. Most torque wrenches have a mark on the handle that shows where to grab your hand and apply force. Use the second hand only at the beginning to position the tool on the screw or nut.

5. Do not use an extension on the handle. This can change the torque and would result in the key reporting an incorrect value.

6. A torque wrench will help you avoid over-tightening, but it won’t prevent it! When the required torque is reached, the wrench control system is “activated” and the operator hears a clear click. If you hear the signal without moving the wrench, the fastener is already too tight. The correct practice here is to start over: loosen the screw again, screw it in with a suitable tool and finish using the torque wrench to safely achieve the correct final torque.

7. Tool maintenance: As a precision tool, torque wrenches must be calibrated or back-tested regularly, and the user is responsible. Don’t forget that if the measuring instrument is dropped or damaged, it must be repaired immediately.

A torque wrench is not only a wrench but also a measuring instrument strictly speaking. It can only be used to determine the torque when tightening fasteners and must not be used as a disassembly tool to loosen the tightened fasteners. When you use a large torque wrench, you can add a long sleeve rod to save effort. If you don’t use it for a long time, you should retract the scale line to the minimum torque value.

By the way, did you know that the output square can be changed without changing the torque wrench?