=?utf-8?B?b3IgYW55IFRvcnF1ZSBWYWx1ZXMgZGVwZW5kaW5nIG9uIHR5cGUgb2YgTnV0?=
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Tony=0Ado you still have the bolt? If so put it in a vice and bend it, it s
hould bend significantly without=0Asnapping. Hi tensile steel bolts normall
y won't bend, that's why we don't use them in aircraft.=0AGraham=0A=0A=0A
=0A=0A________________________________=0A From: Tony Renshaw <tonyrenshaw26
8@gmail.com>=0ATo: "europa-list@matronics.com" <europa-list@matronics.com>
=0ASent: Monday, 28 October 2013, 21:58=0ASubject: Europa-List: AN3 Nut Tor
que Values.or any Torque Values depending on type of Nuts
=0A =0A=0A=0AGidday,=0AYesterday I was tightening by hand one of the two AN
3 bolts that clamp the flap cross tube to the articulating/hinge arms that
are attached in the floor. So, in case there is the slightest movement and
this would exacerbate in my flaps I decided to do them up "tight". Guess wh
at, I snapped one, yep snapped. It broke at the top of the shank where the
thread started, and did NOT strip the thread as many might have presumed. T
his got me thinking that normally most bolts are designed to effect a shear
load, and not normally a clamping load. Anyway, I know there is counter ar
guments to all of this, but what matters is the applicable torque loads we
use if we torque them using a wrench, and I just stumbled upon a reference
I think is important. I found this on an VansForce website, and why it matt
ers is the torque values are NOT for locknuts, which have an inherent frict
ion drag torque value of 14 in-lbs. So, referring to the attached table an
AN3 needs 20-25
in-lbw, but in actuality would be more like 34-39 in-lbs.=C2-=0AI think
this could be easily overlooked, and if the friction drag torque of locknut
s is not taken into account, people are under torquing their bolts.=C2-
=0ARegards=0ATony Renshaw=0ASydney Aussie.=C2-
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