Shox Dr
Chief Engineer to Carlos Fandango
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- Location
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- Thread starter Dieselman 63
- Start date
Dont say it, like it was just ME!! or I had stated that was correct
That is how things USED to be designed and how you WERE taught, there were millions of cars and trucks built with flat washers then spring, then nut, that is how it was.
The same with bolts, flat, spring, bolt head.
If you have a slotted hole under the washer, fair enough, no way round it, until wave and Belville washers became readily available. However I have always assumed the flat and spring washer arrangement was generally because the designer didn't know better. Star and Shakeproof washers are also supposed to grip the nut and workpiece.
Yes, in theory these washers would not stop a nut from starting to loosen, but the positive "dig in" of the spring, star and shakeproof would stop it moving far. That is why I have always been a little suspicious of wave washers, but Germans seem to love them. The Japanese seem to still love split pins.
normspanners
Member
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mereces use spring washers on their wheel nuts!
PhillipM
Member
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They don't work well either - they don't dig in under vibration once the preload has been lost, high frequency vibrations will make them creep across the surface in anything heavily loaded.
Same as spring washers, they just stop the nut/bolt falling out when it's already loose because they're not rigid enough themselves. Obviously if the system can survive in some form with loss of preload that's a good thing, or if for some reason the bolt isn't used tight/torqued (fairing bolts, etc) but none of them stop the bolt coming loose in the first place.
Neither do split pins and lock wire for that matter. They're just there to keep a failure as just that, rather than a catastrophic failure. Same reason as norm says above that spring washers are captive in wheel nuts (PSA have used captive Bellvilles for decades)
