Allowable Stresses
Allowable Stresses
(OP)
How to fix the allowable stresse for the following stress conditions, for mechanical equipment and pressure vessel ? The basis has to be realistic based on research findings since we cannot assume high factors of safety.
Tensile Loading
Compressiver Loading
Shear Loading - Direct Shear
- Torsional Shear
- Thread Shear
Contact Stresses - Surface Contact - Flat to Flat
- Point Contact - Ball to Flat
- Rolling Contact - Flat to Flat
It does not seem to be prudent to take the allowable stresses as per ASME for non-pressure containing members where only a pure mechanical load can be expected.
The allowable stresses recommended by the other texts seem to be too conservative/unrealistic. Hence a rational approach is desired. Will be thankful if some one could throw more light on this subject in detail.
Tensile Loading
Compressiver Loading
Shear Loading - Direct Shear
- Torsional Shear
- Thread Shear
Contact Stresses - Surface Contact - Flat to Flat
- Point Contact - Ball to Flat
- Rolling Contact - Flat to Flat
It does not seem to be prudent to take the allowable stresses as per ASME for non-pressure containing members where only a pure mechanical load can be expected.
The allowable stresses recommended by the other texts seem to be too conservative/unrealistic. Hence a rational approach is desired. Will be thankful if some one could throw more light on this subject in detail.
RE: Allowable Stresses
Contact ASTM, ASME, NASA and various universities to see if they have literature available that describes your loading and materials sufficiently to allow for safety factor reduction.
RE: Allowable Stresses
Tom Worthington
pworthi@astro.as.utexas.edu