Nyloc nuts

Figure 12.8. Locking nuts (a) standard lock nut (b) slotted and castle nuts (c) Nyloc nut(d) Aerotight nut(e) Philidas self-locking nut (f) torque lock nut...

Self-locking nuts are available which are easy to assemble and do not require a hole in the bolt or the use of a split pin. One type, known as a Nyloc nut. Fig. 12.8(c), incorporates a nylon insert round the inner top end of the nut. As the nut is screwed on, the nylon yields and forms a thread, creating high friction and resistance to loosening. 

Provision for anti-vibration mechanisms in the fastening system where necessary, e.g. Nyloc, lock nuts in combination with split pins, spring washers. 

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