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Failure due to torque

Failure due to torque

Failure due to torque


How would I go about finding the max torque that can be applied to 2 jack screws to free up a stuck acrylic plug without causing the flange on the plug to fail?

RE: Failure due to torque


Well it might help if you show us where you intend to apply the jack screws and the material strength of the material you are dealing with. A sketch would help enormously showing where this thing is actually stuck.

“Do not worry about your problems with mathematics, I assure you mine are far greater.” Albert Einstein

RE: Failure due to torque

As per my understanding, you want to apply torque on the any of 2 screws of shared image acrylic product flange to remove it from some sort of part/assembly below it when its stuck on the part. This is very little information to suggest anything. More detailed information is needed.

You need to consider the weight that is supported by this flange + acrylic product weight, lets call it W. The you need to overcome frictional force = coefficient of friction between the acrylic produce and surface of part on which it sits*W to move it. Based on this you can calculate the torque=force*distance up to screw from center if torque applied at center and not on the screws.

RE: Failure due to torque

Any idea what caused the plug to become stuck? It sounds like it's less a friction problem, and possibly more of an adhesion problem, or did the plug get cocked sideways and jam? Irregardless, if it were me, I would get a new one ordered or start machining a replacement...and then not waste time on analysis, just go ahead and try to jack it out carefully and slowly advancing a screw in each (4x?) of the tapped holes, and have a couple of drills and taps (and a hammer and chisel) on hand to tap the body of the plug to pull it once the flanges have snapped off, and then drill the remainder of the plug out when the body shatters, and carve out the remainder with hammer and chisel.

RE: Failure due to torque

It seems to me that if you really want to preserve the flange, then you need to spread the load out and use as many screws as practical and "walk" the plug out by making the same number of turns on diametrically opposed screws. You'll be able to see if the flange is going to go south if it starts bending significantly. WD-40, etc., might help, along with some gentle, or not-so-gentle, nudging/impacts.

TTFN (ta ta for now)
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