What’s a Safety Bolt?

Print anything with Printful



A safety bolt uses a locking wire system to prevent loosening from vibration and impact forces. It is commonly used in high-stress applications such as aviation and motorsports. The wire system provides a visual inspection aid and is an inexpensive way to secure fasteners. It is often a statutory safety requirement and requires only a simple tool to apply. Safety wire tabs can also be used to improve effectiveness.

A safety bolt is an industry standard fastener that uses a tension locking wire system to prevent inadvertent loosening from vibration and impact forces. Has a hole drilled through the head to accept a locking safety cable. The locking wire system also serves as a visual inspection aid to verify that the fasteners are properly tensioned. The shear bolt is commonly used in applications that place extreme mechanical demands on machinery such as aviation and motorsports.

Fasteners used in machinery exposed to extreme structural stresses during normal operation are prone to loosening over time from continuous impact, vibration and torque distortion. The failure of a critical fastener in these high-stress applications could have serious implications. A particularly simple and effective way to prevent this from happening is to use a shear bolt system. This system is inexpensive, quick and easy to use, and provides both an extra layer of security and a clear visual indication of the integrity of the fasteners.

Security bolts have a small hole drilled through their heads which allows a length of specially made wire to be wound around and an adjacent fastener head or other anchor point then twisted to hold tension on the two. The thread is inserted in such a way as to maintain tension in the tightening orientation of the bolt thereby preventing it from vibrating loose. The wire is a malleable material which holds it in shape once tensioned and will continue to maintain the locking action until removed.

This wire lock ring also allows anyone inspecting your installation to ascertain at a glance if the fasteners are still secure. In applications such as aircraft and auto racing, the use of shear bolts is often a statutory safety requirement and a standard part of pre-use checklists. The same locking principle is also used to secure clevis pins to shackles and other applications where loss of fasteners could cause injury or damage. The simplicity of the lock bolt system also makes it an especially cost-effective way to lock down fasteners, an attractive option considering the cost of the systems they typically secure.

Security bolt thread is available in a variety of different gauges and materials and requires only a simple tool to apply. The most commonly used gauge and material is 0.032 inch (0.8 mm) stainless steel wire, and the tool used to tension the wire is a simple, specially made device that looks like a regular screwdriver. Safety wire tabs are also commonly used to improve the effectiveness of the safety bolt system. These tabs look like a standard tab washer with one tab longer than the other with a hole in the end. The bolt is tensioned on the washer in the normal way and the washer tabs bent up to contact the bolt head, then locked in place through the tab hole with the safety wire.




Protect your devices with Threat Protection by NordVPN


Skip to content