Re: [SystemSafety] Wheel detachment from a moving car / redundant prevision thoughts

From: Stachour, Paul D BIS < >
Date: Wed, 27 May 2015 13:33:20 +0000


Heath & all,

With regard to redundant methods,

    Yes, it might very well be that the taper-set made the technique of different-turning bolts/lugnets redundant. However, even if so, I don't believe that would be a good reason to remove one of the redundant solutions.

After all, at road/rail crossings, we often have

1) flashing lights
2) safety-gates
3) train-horns

to attempt to prevent road/rail collisions.

I doubt that there are many who would advocate removing 2-of-the-3, because "one *should* be enough".

[Not too long ago, in a letter-to-the-editor in the Minneapolis Star-Tribune, a reader even *claimed* that a crossing safety-gate that did not come down properly was the *CAUSE* of a road/rail collision.]

Sigh. Regards, ..Paul S.  

Paul D. Stachour
Software Quality Assurance
 Det-tronics|6901 West 110th Street, Bloomington, MN 55438 USA 952-941-5665, x8409
Paul.Stachour_at_xxxxxx
www.det-tronics.com



> I heard of the Chrysler way (maybe some German manufacturers also did
> it?), but it just didn't seem to be worth the hassle because if
> tightened properly, wheel nuts just didn't fail.

I find it very hard to believe the assertion that this technique ever solved the problem, or that it hasn't been supplanted with better techniques. It was pre-1960 technology and I believe that the taper seat made that technique redundant. Note that the taper seat will only keep tight nuts tight, not prevent loose nuts from vibrating loose. It's very hard to imagine the direction of the thread has any influence on the behaviour lug nut, but I eagerly await to be shown otherwise.

Heath



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systemsafety_at_xxxxxx Received on Wed May 27 2015 - 15:33:40 CEST

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