Explain the term self-locking nut - Leaving Cert Engineering - Question c - 2007

A self-locking nut is a type of fastening device designed to prevent loosening under vibration or rotational movement. It typically incorporates a nylon insert that engages with the screw threads, creating additional friction. This frictional force effectively locks the screw in place when tightened, ensuring a secure connection. As the screw is turned, the threads cut into the nylon, which helps to hold the nut firmly and resist any tendency to loosen, thus maintaining stability in mechanical assemblies.