Torquing - the “art” of tightening fasteners to the perfect level. While, for the average users of nuts and bolts, it might seem unimportant or even trivial, torquing fasteners incorrectly will lead to serious consequences which could damage the entire structure, machine or component you have built. If, like most fasteners users, the maximum you have done to torque your screws is to grab a proper size wrench and tighten the screws, then this article will shed some light on how else you can improve your fastening abilities.

Torquing to perfection is actually a complex process which requires an almost engineering level expertise on how to handle fasteners. The effect of perfect torquing can go a long way in extending the life of the fasteners as well as the component you are building with it. In fact, the short lives of several structures could be attributed to improper fastening. Now that we have understood the importance of proper torquing, let us focus on the basics of the process it self.

The Why and How

The human requirements for proper fastening are input torque and angle of turn. But there are tens of other factors which affect the longevity of the fastening hold between different objects. One of the leading causes of failure while fastening is insufficient tightening and improper levels of preload. This leads a higher rate of fastener fatigue. Insufficient torque is capable of notwithstanding small movements and vibrations in the assembly which can even create a weakening crack in the fastener.

While loading a nut onto a bolt, two key things you need to keep in mind are the types of stress you will be putting the fasteners through - tension and torsion. Between these two, tension is the desired stress while torsion is an undesirable form of stress which is caused by friction. This is one more area where torquing is crucial - it overpowers the friction to nullify the effects of torsion.

The Process of Torquing

Like we mentioned before, torque and turn are fundamentally how you can control the way you fasten a bolt and nut; in other words, by controlling these parameters, you can save yourself from decades of costly repairs and replacements. Bare with us so that we breakdown the exact process of how to tighten a fastener and how you can improve it yourself.

Basically, the standard procedure for tightening a fastener involves turning, advancing and torquing to produce the required tension in the fastener. Here are the things which will happen to in the same process:

  • Rundown - The fastener is turned until its head touches the bearing surface.
  • Alignment - To achieve the optimum contact, the fastener and bearing surface are aligned properly.
  • Clamping Range - The constant slope of the the torque-angle curve.
  • Post Yield Zone - In this, a portion of the components yield to achieve the required tension.

How to Improve

In this whole process, how can you hope to improve your torquing abilities?

  • Determining torquing requirements by analysing specifications like bearing surface material, fastener material, environment of operation, and strength of the joints.
  • Using the right tools like perfectly calibrated wrenches.
  • Or you could simply use high end torque analysers to store and read several lab generated tests. If you run a large scale project, you should run several variations in simulations and choose the best result.

Additional Tip:

To ensure that your project is safe from any type of torquing errors, we recommend that you conduct periodic checks on the fasteners.

At ITA Fasteners, we distribute high quality fasteners to several countries. You can browse our website for a comprehensive list of products we have or reach out to us on sales@itafasteners.com for any other queries.

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