Are nylon insert lock nuts effective
against bolt loosening?
Locking nuts work to secure bolted joints by adding friction to the thread of the bolt. Different varieties of locking nut exist, those that utilize metal to create friction, such as the all metal nut, and those that incorporate a polymer in the design, such as the nylon insert nut. Locking nuts follow the same installation procedure as normal nuts. The nylon insert nut features an internal nylon washer or patch.
The addition of the non-metal component means that the nylon insert nut is more temperature and chemical sensitive. It also necessitates the use of a tool for installation, however, the revolution speed must be less than 150 RPM in order to avoid over heating the nylon insert.
Read the full version in the eBook "Why do bolts loosen?"
(A comparison between common bolt securing options)
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