Security Lock Nut

Specifically targeting the issue of loosening fishplates the Security Lock Nut replaces the standard nut and spring washer in a plated joint and offers years of service without loosening.


Type approved by major railroads in North America including Union Pacific and BNSF, Security Lock Nut is saving time and money through reduced inspection and maintenance on plated joints.  Trials are currently underway with ARTC and Metro Trains. 


Minimize maintenance costs, reduce downtime, and improve reliability by utilizing Security Locknuts. The patented vibration-resistant products provide peace of mind because they “won’t back off” and are proven to perform in the most demanding applications. Engineered with a durable spring steel alloy, Security Locknuts do not damage or deform the bolt thread. Security Locknuts require no special tooling, can be quickly and easily installed, and can be reused, saving you time and material costs. 


Standard sizes are outlined below for mating fishplate bolts.


Use the Locknut selector for access to the full range of part numbers and drawings.