As an Amazon Associate I earn from qualifying purchases
Torque wrenches are used to tighten nuts and bolts to a preset torque value.
Determining the correct torque value helps tighten fasteners to the best level of tension to prevent over or under tightening.
Over tightening can cause damage from strain and under tightening can allow the pieces being fastened together to fall apart.
What Does Torque Mean?
Torque is a measurement of how much a strain on an object will cause it to rotate. The pivot point is the axis the object rotates on. Torque can be measured in lb.-in. (pound inch), lb·ft. (pound-foot), or N·m (Newton meter).
What are Torque Wrenches Used For?
Torque wrenches have a wide variety of uses, from simple repairs at home to construction of heavy machinery and buildings.
Because they work to tighten screws and bolts to the most secure setting, the use of torque wrenches helps assure safety in any project.
Different Types of Torque Wrenches
There are many different types of torque wrenches with various uses. Here are some of the most commonly used torque wrenches and what they are used for:
Electronic torque wrench
Another name for the electronic torque wrench is digital torque wrench. It is named after the electronic sensor it has that senses how much twisting force is applied and displays this information on a digital screen. Electronic torque wrenches typically come with a memory stick that can be used to save readings which can be uploaded and viewed on a computer.
Beam torque wrench
Beam torque wrenches are typically simple to use and inexpensive. They include a scale that stops at the right number once the correct level of torque is reached.
Click torque wrench
Click torque wrenches are named after the sound they make when the user reaches the correct torque setting.
Hydraulic torque wrench
Hydraulic torch wrenches are most commonly used in an industrial setting. This type of torque wrench reaches the correct level of torque through the use of hydraulics.
Micrometer torque wrench
Micrometer torque wrenches are often used in transporting and manufacturing cargo. The scales measure the weight of the load and this accuracy is important when transporting heavy loads of cargo by ship, plane, or train.
Dial torque wrench
Dial torque wrenches are usually wider than other types, so it is not ideal for use in smaller spaces. They are considered one of the most accurate types of torque wrenches. Dial torque wrenches are commonly used in the automotive and aerospace industries.
How Do Torque Wrenches Work?
Torque wrenches are calibrated to apply a predetermined amount of torque to a nut or bolt. The level of torque applied will depend on the length of the wrench and the amount of force on the handle. The formula to determine the torque is force x length = torque.
The handle of a torque wrench has an indicator connected to a calibrated scale. Once the indicator displays that the desired torque has been reached, the user can stop twisting the bolt.
Torque wrenches can be set to read in lb.-in. (pound inch), lb.-ft. (pound-foot), or N·m (Newton meter), depending on the type of project and the user’s preference. It is important to use torque wrenches that have been calibrated for accuracy and safety.
How to Use a Torque Wrench?
To start, torque wrenches often include a lock that must be unlocked before use. The lock keeps the handle from rotating. After unlocking, rotate the handle of the wrench to align the number on the handle with the center line on the barrel. Relock to keep the settings adjusted during use.
If you are using a click torque wrench, hold the pivot in place with one hand while rotating the handle in the other until it makes a clocking sound. Once it clicks one time, stop turning immediately. It is important not to exceed one click as this can over tighten the fastener and damage it or the materials being fastened together.
When finished using the torque wrench, return all settings back to the lowest setting. This helps the wrench keep its accuracy for future measurements.
Note that instead of using a torque wrench on a fastener that has already been tightened with another type of wrench, it is better to loosen to remove the fastener and then re-torque it to the correct setting in order to avoid over or under tightening the fastener.