Torque wrench: work and cost

A torque wrench is a tightening tool. Particularly used in mechanics, it allows you to tighten a part with a given tightening torque. In cars, manufacturers recommend tightening torques that must be observed: this is what a torque wrench allows.

⚙️ How does a torque wrench work?

La Wrench it is a tool that allows you to tighten a bolt or part to Torque specific. Tightening torque is a force expressed in newton meters (Nm) or kilometers (m.kg). In automobiles, many parts must be tightened to the torque specified by the manufacturer.

Thus, the torque wrench allows assembly as recommended by the vehicle manufacturer. It is a precision tool that mechanics cannot do without. In fact, not observing the correct tightening torque can damage the part and its nuts.

Usually the torque wrench is adjusted according to the tightening torque. But there are different types of keys:

• Electronic torque wrench : As the name suggests, it features an electronic screen and often a beep to indicate when the tightening is correct. These keys are easy to use and very accurate, albeit slightly more expensive.
• Trigger Torque Wrench : adjustable or fixed value, this type of wrench has a signal that eliminates the need for torque control.
• Direct reading torque wrench : during this, the tightening value is displayed, so it must be checked.
• Power steering torque wrench : used for very high tightening torques.

For small tightening torques, there are also torque screwdrivers, the torque of which is expressed in centi-newton meters (cNm).

👨‍🔧 How to use a torque wrench?

Tightening torques are commonly understood in automobiles. from 20 to 150 Nm... You can buy fixed-value torque wrenches or choose an adjustable model that can be used on a variety of parts. Tightening is carried out to the signal from the torque wrench.

Material:

• Automotive technical review
• Torque wrench

Step 1: Determine the tightening torque

The tightening torque depends on the part: it is therefore recommended that you consult your service book or your vehicle's Automotive Technical Review (RTA). After checking, activate the torque wrench several times if using it for the first time: this will lubricate it evenly.

Step 2: adjust the torque wrench

There are torque wrenches with a fixed value: in this case, just make sure it matches the tightening torque of the corresponding part. Otherwise, torque wrench adjustment will be required. It depends on the type of key: this can be done electronically or by turning the key handle.

Step 3. Tighten

Install the torque wrench correctly: it must be vertical to the bolt as its force is perpendicular. Tighten the wrench until the tightening value is reached: depending on the wrench model in question, you may have a sensitive or audible signal (click), or you may have to read a screen. Stop tightening as soon as the value is reached.

🔍 How to choose a torque wrench?

There are many models of torque wrenches on the market. For a car, it is usually understood the tightening torque of parts. from 20 to 150 Nm... Special wrenches allow you to use less torque, for example, for bicycles, or more for large machines.

We advise you to choose adjustable torque wrench instead of buying a fixed cost model. Indeed, you will find different tightening torques on your car, and in the end it will be cheaper for you to buy one adjustable wrench than several models of different denominations.

To select the correct torque wrench, you must pay attention to its type. The most modern ones are electronic or digital, with a digital display and much simpler and more accurate adjustment. They are easier to use and more expensive.

Less expensive models often require manual adjustment by turning the end of the wrench and checking the value while tightening. Thus, these keys are less easy to use.

Therefore, we recommend that you choose trigger torque wrench, preferably electronic. Practical, easy to use and effective, it also needs to be purchased at a variable, rather than a fixed cost, in order to be versatile.

💶 How much does a torque wrench cost?

You can buy a torque wrench from a car store (Norauto et al.) Or a tool store (Leroy Merlin et al.). The price varies as it depends on the model and type of key. First prices start around 20 €, but a professional torque wrench may cost up to 400 €.

Now you know how to use a torque wrench and how to choose the right one! An indispensable assistant for a mechanic, even an amateur, it is necessary to tighten parts and bolts with the correct tightening torque. Remember to strictly observe the tightening torque recommended by the manufacturer and stop tightening as soon as it is reached.