[SEL] semi - ot lock washer questions for engineers

[Curt]

Bill,
Oh here we go again! Sometime back I made the statement that lockwashers 
were indeed useless devices. Several flame making devices were aimed my 
way. But reading any good engineering text on bolted connections will 
quicky show that they really are not needed for properly sized and 
torqued bolted connections. Hardened flat washers in conjunction with 
correct nuts and proper preload is as good as it gets.

In the connections that works loose and are rattling around there is 
probably some merit to using lockwashers however.

Part of the reason I was flamed so badly was my bold statement that the 
rounded edge of square nuts should go against the part being clamped. 
That debate has raged on a while and I remained convinced that there is 
merit to this method. One reason lock washers may have become so popular 
is that when using square nuts to bolt structural steel together, the 
square nuts will dig into the steel making tight connections difficult. 
By putting a small OD lockwasher under it this keeps the corners from 
digging in. However, by turning the nut over and putting the rounded 
side down, then you don't need the usless lockwasher anyway.

I could try and dig up the washer info if you like. For now I'm prepared 
with Nomex suit on :-)
Curt Holland
Gastonia, NC
P.S. Use Loctite or ESNA nuts if you want secure non-high strength 
bolted connections.

bill at antique-engines.com wrote:

>Debate flaming on in some forums:
>"Split-type lockwashers" good, bad, worthless or worthwhile?
>Some claim they are worthless and modern farm machinary, autos, engines
>and other equipment don't use them because they are worthless (not due to
>cost savings)
>
>Others claim it's due to cost savings.
>
>Are they worth using, do they do any good?
>If so, what applications do they work in, which do they not work in?
>Can you support or back up your claims?
>
>I've always used them and can't say they do any harm, but I also can't say
>it would work just as well without them because I haven't done
>side-by-side experiments.
>
>Bill
>Runnells, IA
>(where things may be coming apart due to lack of lockwashers?)
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