If we asked a handful of maintenance engineers what exactly they are trying to achieve when they tighten a bolt, it’s likely that we’d receive a wide range of answers. Strictly speaking, when we tighten bolts, we’re trying to stretch the bolt enough so that the elastic tension within it clamps the assembly together. That’s right – it’s one that’s easier done than said! In a perfect world we would always recommend measuring the tension in the bolt, as opp...

When it comes to torque wrench calibration, I often get asked ‘When should I re-calibrate my torque wrench? And should I wind it back to zero after use?’ In fact, these two questions might well be the most frequently asked of all frequently asked questions and are rightly a subject of genuine concern for production and quality managers. To misuse the old wartime propaganda slogan a little, ‘Careless torque can cost lives.’ When it comes to matters of recalibration, I...

One of the more frequently asked questions from our customers is ‘how do I select the correct torque wrench for application?’Generally, most torque wrenches are used for tightening nuts and bolts accurately. Nuts and bolts need varying degrees of accuracy depending on the materials being fastened together, and therefore, there are different wrenches for different applications. The two main reasons why we use torque wrenches are to achieve the correct level of tightness and then ...

Like most drivers I often take my car into a franchised dealership or an independent garage for a change of tyres. Usually, the mechanic removes and then replaces the wheel with a torque wrench. All generally goes well until the first click of the wrench which signifies that the nut has been tightened to its optimum torque. However, all too often in my experience the mechanic continues to tighten the nut beyond its optimum torque. In the past, I have counted two, three and even four clicks ...

This might well be the most frequently asked of all frequently asked questions and is rightly a subject of genuine concern to production and quality managers. To answer the question, I am going to look to the standard BS EN ISO6789 - Assembly tools for screws and nuts - Hand torque tools. Requirements and test methods for design conformance testing, quality conformance testing and recalibration procedure. Unsurprisingly, most of us refer to it as ‘the torque wrench standard’&nbs...

According to ‘Brake’, the road safety charity, runaway wheels kill 8 to 10 people and injure many more each year in the UK. Naturally, as a torque solutions provider and torque tool manufacturer this is very concerning and our fear is that the issue is not given its due attention by the road haulage and public service vehicle industries where speed and low cost often seem to be the most important factors in wheel bolting. lt’s very important that maintenance engineers...

For the many of you who probably don’t know, Norbar is a family owned and run business. Whilst in 2012 we have quite the global reach, we did have more humble beginnings. How does that phrase go again? You don’t know where you’re going until you know where you’ve been? Well, here’s a potted history of our life so far. In 1942, at the height of World War 2, Bill Brodey was engaged in selling various tools and machines including Joseph Sunnen honing machines used...

Certainly, if a torque wrench is wound back at all it should not be adjusted below the minimum scale marking (usually 20% of maximum) - never to zero as this can adversely affect the calibration of the wrench. Beyond that, it really depends on the application. We have thousands of Production Type wrenches in service that are left at their setting for months on end without a problem. Whilst the occasional user should adjust back to the minimum scale setting after use, if you use the wrench in an ...