Torque wrenches are common place across a variety of industrial processes, commercial garages and even homes wherever there is a precision assembly process utilising threaded fasteners. Considering their widespread use however, there remains a number of things that people get wrong or simply don’t know. Here Philip Brodey at Norbar Torque Tools highlights the top ten things to consider.
1. Storing your torque wrench
When a torque wrench is in regular use it does not need to be wound back. However, when storing a torque wrench for an extended period of time, users should always wind it down to the minimum scale setting and never to zero.
A fully loaded torque wrench, left in storage for a long period, can cause a ‘set’ in the spring, causing it to weaken over time. On the other end of the scale, by completely off-loading the spring, other components within the wrench may move fractionally relative to each other. When you reapply spring compression the orientation of these components can change, therefore affecting accuracy. All in all, it is better to leave a bit of compression in the spring while in storage.
2. For accurate results, one click is enough
Users often allow torque wrenches to click multiple times, without being aware of the additional torque being applying to the bolts. Operate your torque wrench in a smooth and steady manner and remember that one click is enough.
3. Using your wrench on an anticlockwise thread
Many torque wrenches will only indicate in the clockwise direction. Therefore it is necessary for users to always check the wrench’s specification before using it on an anti-clockwise thread to ensure the tool is suitable and, prevent a loss of torque control. Examples of left hand threads include the left hand wheel nuts of certain vehicles and the left pedal of bicycles.
4. Converting between torque units
Converting torque units can be tricky but is a very precise process. To help users calculate units more easily, they can turn to Norbar’s calculator app available on IOS and Android. Alternatively, the calculator is also available online at www.norbar.com/en-gb/Home/Torque-Unit-Converter
5. Adjusting your torque wrench
Equipment manufacturers will always provide the required torque for any given piece of equipment and so when adjusting your torque wrench it is important to ensure that these levels are met. Remember to always adjust the wrench up the scale to the required torque figure to ensure accurate setting.
6. Using marked loading points for accurate results
Most torque wrenches are length dependent and feature a marked loading point on the handle but, many people don’t use it. For accurate results, most torque wrenches have to be operated with your hand centred over the marked load point. It is also essential that this load point is observed when it comes to calibrating the torque wrench.
7. Using torque wrenches for undoing
So long as users operate with caution and do not exceed the maximum torque, most torque wrenches can be used for undoing. However, if the bolt will not free within the maximum torque of the wrench, another tool should be used instead. By exceeding the maximum torque limit during a bolt loosening you can affect the wrench accuracy, causing problems for future use. If in any doubt, use another tool for loosening bolts.
8. Adding extensions to the torque wrench handle
Users should never put a pipe or any other kind of extension onto a torque wrench handle as doing so can seriously damage the tool and make it inaccurate, never mind the potential safety hazard.
9. Locking it in
It can be all too easy to accidentally adjust the settings of a wrench during use so, if your torque wrench is fitted with an adjustment lock, you should always apply it before operating the wrench in order to avoid any unintended changes.
10. Applying ‘crows foot’ type fittings to a torque wrench
‘Crows foot’ type fittings can be applied to a torque wrench square drive but they will alter the torque. It is therefore important that a suitable offset is applied to the set torque. For guidance with setting offsets, users can download Norbar’s Torque Extension App for IOS and Android.
Keeping this advice in mind will see users getting more from their tool, with the wrenches becoming more accurate and lasting longer. The tips are simple, but the implementation of these basic rules can often be forgotten and that’s when mistakes can happen.
We hope that users will see the benefit of this advice, take on board the comments and apply them, ensuring accurate results and the safety of applications.