When using fasteners such as Nitronic 50 hex lab bolts or Monel 500 carriage bolts, a common issue you will often have to deal with is bolt and nut failure. This is defined as a situation where the fastener used becomes structurally unstable, which in turn means that you would need to get rid of it and replace it with another type of bolt.
As you can imagine, having to do this on a regular basis is not a good thing. You are likely to waste a lot of time identifying the failed bolts, and may also spend a lot of time removing them and replacing them as well. If the bolts are used to put in place critical structures such as pillars, their failure could also have safety implications as well.
The best way to deal with this problem would be to prevent it from happening in the first place. There are a number of ways of doing this, including the following:
The use of bolts that are designed for the purpose you will use them for
The commonest reason why bolts and nuts fail is because the wrong ones were chosen for the job. When you are making a decision about which type of bolt should be used for a particular application, you have to take into account the issue of the stresses and other conditions that the bolt will be subjected to. For instance, if it turns out that the bolts are going to be subjected to a high degree of tension, you would need to ensure that you get one that is made to withstand this. You should also account for environmental factors that will interact with the bolts, including humidity and heat. All these can contribute to change the physical and chemical nature of the bolt, leading to failure in the long run.
How many bolts should you use?
Another important issue to consider is the number of bolts to use in such a setting. There are some structures that will be subjected to low forces, in which case only a few bolts can be used safely. However, if you are designing a structure that will be subjected to very large forces, such as a ship’s hull, it would be wise to increase the density of the bolts in that area. This way, all the forces will be distributed evenly across all the bolts. This will in turn reduce the risk of failure, since each bolt will have to deal with a lower degree of force.
Proper fastening methods
Everything to do with fastening, from how you drill the pilot hole to how you treat the bolt after it is in place, will affect how long it will last. Always ensure that you find out how to do this effectively, so that you don’t end up regretting later on.
In summary, there is quite a lot you can do to reduce or even eliminate the chances of structural bolt failure. Always remember that all these issues will save you time and money, which makes them worth it.
Started my career in the fastener world in 1969 at, Parker Kalon Corp. a NJ based screw manufacturer located in Clifton, NJ working in inventory control, scheduling secondary production and concluding there in purchasing. In 1971 I accepted a sales position at Star Stainless Screw Co., Totowa, NJ working in inside sales and later as an outside salesman, having a successful career at Star I had the desire with a friend to start our own fastener distribution company in 1980 named: Divspec, Kenilworth, NJ. This was a successful adventure but ended in 1985 with me starting Melfast in August 1985 and have stayed competitive and successful to date. Melfast serves the OEM market with approximately 400 accounts nationally.