Shear nuts and shear bolts are amongst the many different types of security fastenings available from Insight Security. The extensive selection of available security fastenings can be bewildering so in this post we are focussing on shear nuts and shear bolts. But remember that if you have any questions about secure fastening and what you need for your application, please don’t hesitate to contact Insight Security.
Table of Contents
What are Shear Nuts?
Shear nuts are a form of versatile, one-way security fastening that doesn’t require any special tools. They consist of a threaded conical section with a non-threaded hexagonal section that’s used to tighten them. Once tightened using a standard spanner or socket drive, additional pressure will exceed the shear-torque of the nut and shear off the hexagonal section, leaving only the tightened, smooth, secure conical section in place. Shear nuts are available in stainless steel, bright zinc plated steel or galvanised steel.
What is a Shear Bolt?
Shear bolts, like shear nuts, are a type of one-way security bolt used in situations where permanent, secure fastening is required. They are ‘one-way’ because, once the bolt is secured, it cannot be easily removed.
How do Shear Bolts Work?
Shear bolts are sometimes called snap-off bolts or shear screws. They are used in the same way as standard bolts, but once fully-tightened the hexagonal shaped head section is snapped-off, leaving only a secure, tamper-proof dome or countersunk head that cannot be gripped with pliers or mole-grips.
Installation is simply achieved using a standard spanner or socket drive, there is no need for special tooling. The bolts are designed so that the hexagonal head section shears off once the bolt has been tightened. Shearing is brought about by exceeding the shear-torque required by the bolt.
Where are Shear Nuts and Bolts Used?
The ease of installation using standard tools and low cost of shear bolts and nuts makes this form of secure fastening a firm favourite with local authorities. They are extensively used in a wide range of applications such as securely fixing park benches to concrete bases and security fencing.
Beyond local authorities, shear nuts and bolts are used by various government agencies including the Environment Agency. Businesses of all sizes are using shear nuts and bolts to improve security and reduce vulnerability. And homeowners are increasingly enjoying the benefits provided by secure shear nuts and bolts in reducing susceptibility to crime and vandalism.
What is Shear Strength?
Shear strength is defined as the maximum load that can be supported by a bolt, applied at right angles to the bolt’s axis, before it fractures. Shear nuts and bolts are designed such that the hexagonal sections used to tighten them up will shear off once the nut or bolt has been tightened to the required torque.
Need for Secure Fastenings
There is widespread need for secure fastenings to ensure safety and security. In and around the home, replacing standard screws, nuts and bolts with secure, tamper resistant fastenings will significantly improve security. In workplaces, replacing standard fixings with tamper-resistant secure fastenings will raise levels of safety and security. And importantly, in public areas such as parks and around public services such as transport, using secure fastenings reduces the levels of vandalism, damage and theft.
