bolt shankfails in tension before threads fail in shear
bolt shankfails in tension before threads fail in shear
(OP)
I read that typical bolt sizes are designed so that for a bolt loaded in tension, the shank will fail before the threads shear.
I can understand why that's a desirable feature. But I can't understand why it's so.
Tensile Stress on shank is F / Ashank
Sheat Stress on threads is F / Athreads
I would think Athreads is < Astem since only a few threads are active (right?). That suggests the shank tensile stress is higher than the thread shear stress.
Further, the material limit for shear stress is likely lower for shear stress than for tensile stress.
I know I am obviously missing some big parts of the picture. Can someone please explain.
I can understand why that's a desirable feature. But I can't understand why it's so.
Tensile Stress on shank is F / Ashank
Sheat Stress on threads is F / Athreads
I would think Athreads is < Astem since only a few threads are active (right?). That suggests the shank tensile stress is higher than the thread shear stress.
Further, the material limit for shear stress is likely lower for shear stress than for tensile stress.
I know I am obviously missing some big parts of the picture. Can someone please explain.
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RE: bolt shankfails in tension before threads fail in shear
Not sure whether this is what your missing but the internal thread of any size always as a bigger shear area than its male counterpart.
Have a look at this site:-
http://ww
RE: bolt shankfails in tension before threads fail in shear
RE: bolt shankfails in tension before threads fail in shear
Here is a calculation:
thread725-35222: Tensile capacity/minimum engagement
Regards,
Cory
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RE: bolt shankfails in tension before threads fail in shear
RE: bolt shankfails in tension before threads fail in shear
RE: bolt shankfails in tension before threads fail in shear
http://www.hexagon.de/dose/dose-1e.pdf