Author Topic: Shear strength of fasteners  (Read 466 times)


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Shear strength of fasteners
« on: March 31, 2018, 12:09:03 PM »
Hi Bob, I have read you like to counter bore an end plug or valve to have the SHCS
Head be the shear member. How deep does the socket head need to be to attain this benefit?
Thx, John

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Re: Shear strength of fasteners
« Reply #1 on: March 31, 2018, 12:26:04 PM »
If the socket in the valve is a decent fit in the valve pocket, then half the head thickness should be OK for a standard SHCS (where the head thickness is the same as the screw shank diameter).... If you are using a low-profile SHCS, it becomes a bit more questionable.... I would tend to assume that the shank diameter is in shear in that case....

Don't forget to deduct the area of the hex hole from the cross sectional area of the head when you do your shear calculations.... and only use 60% of the UTS....

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