Internal ACME Thread 1

[Matt2107]

Hi

I have a doubt that's really bothering me for a while.
I understand that the shear area of ACME pin threads are smaller than the box thread. The pin threads would fail before the box thread does and that's why there is an external ACME thread shear area formula mentioned in Machinery Handbook.
What concerns me is if the box thread material is of a much lower strength material than the pin threads, then there are chances that the box thread would fail first right?
Is there a formula to calculate the shear area of internal ACME threads ?

Please enlighten me with your thoughts. Thanks in advance.

Mathew

 

[jmec87]

Yes, if the box is much lower strength than the pin, it might fail first.

I don't know if there is a published formula for the shear area of internal ACME threads, but it is relatively easy to derive. Figure out how the Machinery Handbook formula for the pin thread determines the shear area (sketching it out could help) and then adapt it for the box thread.

 

[hydtools]

For reference:


Ted