Thread resistance reference
Thread resistance reference
(OP)
Hi,
I'd like to make my calculation sheet more formal.
Some one has a reference for the calculation of non-standard-thread resistance?
I use some basic formulas but I don't have a reference of some norms, textbook,...
Thank you
I'd like to make my calculation sheet more formal.
Some one has a reference for the calculation of non-standard-thread resistance?
I use some basic formulas but I don't have a reference of some norms, textbook,...
Thank you





RE: Thread resistance reference
Are you talking resistance to being torqued down?
This would be massively affected by the material, the finish, the fabrication method and by the clearances in the thread. Is a formula even possible?
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JHG
RE: Thread resistance reference
I don't remember seeing a way to calculate it, other than extrapolate the test data for a thread size not in the table but all other conditions being met (material, finish, lubricants, etc).
But usually a thread torque table is very thorough and doesn't leave out any of the common sizes.
Can you tell us what thread form you are using? It is possible that a running torque table already exists, but we can't find it unless you tell us what it is.
STF
RE: Thread resistance reference
RE: Thread resistance reference
I used to count sand. Now I don't count at all.
RE: Thread resistance reference
I find the shear area of the thread, calculate the stess in the area and check against the tensile strengh of the material.
I'd like to know if there is an official source about how to calculate the shera strengh of the thread.
We build hydraulic cylinder, we use the thread for the head. We use thread from the small M6,M8 up to M400 and bigger, with pitch up to 12 mm.
RE: Thread resistance reference
That is a completely different question. Thread stripping is discussed in the Machinery's Handbook. Look under Fasteners, Torque and Tension in Fasteners, and Length of Engagement.
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JHG