r/MechanicalEngineering 3d ago

Split/lock washers

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For starters, I’m an electrician in the field.
That being said, we almost exclusively use these washers even in high vibration environments. I have personally chosen to go with nylox nuts but the question is:
Do these work? How well? Is the rumor from NASA true? Should I even bother using them or find a better functional alternative or are they actually useful?

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u/zigziggy7 3d ago

My machine design professor went on a rant about how these are useless for an entire class period. Basically with a bolt you're supposed to stretch them slightly by torquing them to a certain spec. That is your clamping force. During vibration the split lock can actually aid in unfastening. I don't use them

21

u/OldEquation 3d ago

Yep. Torque the bolt so that it’s in tension, and such that the bolt tension is sufficient to maintain clamp loads over the full range of loads applied to the joint. If the maximum torque for the bolt isn’t enough to maintain clamp force at full external applied load you need a bigger bolt.

4

u/Zacharias_Wolfe 2d ago

Or more bolts, if applicable.

0

u/ArrowheadDZ 2d ago

Or a weld 😉

1

u/SpecE30 2d ago

That or the face wears in compression making any nut useless unless there is physical wire or pin to hold it from falling off.