Castle 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...

Slotted and castle nuts are used in conjunction with wire or a split pin through a hole in the bolt to prevent the nut from working loose. Fig. 12.8(b). 

Slotted and castle nuts are used in conjunction with wire or a split pin through a hole in the bolt to prevent the nut from working loose. Fig. 13.9(b). 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. 13.9(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. 

Charles Nutting, MD Radiology Imaging Associates 401 Castle Creek Rd Aspen, CO USA... 

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