Acceptable deflection of a 25mm solid steel shaft
Acceptable deflection of a 25mm solid steel shaft
(OP)
I've calculated the deflection of a 25mm shaft to be 2.2mm. Is this too much or is it acceptable?
Fairly basic question I know but it's been a long day!
Fairly basic question I know but it's been a long day!





RE: Acceptable deflection of a 25mm solid steel shaft
In what context?
How long of a shaft?
What cross section?
...
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Acceptable deflection of a 25mm solid steel shaft
Circular cross section, solid, and made of stainless steel, with a length 1161.2mm.
It's supporting a bowl of liquid that will be filled up and then emptied a dozen times a day.
RE: Acceptable deflection of a 25mm solid steel shaft
I would look at the stress in the shaft and then consider the fatigue as the shaft is loaded and unloaded.
Try to get the stres i the shaft below half its tensile strength if possible,then fatigue might not be such a problem.
desertfox
RE: Acceptable deflection of a 25mm solid steel shaft
Why does deflection matter to you?
- Your shaft ought to not break, hence desertfox's remarks, above.
- You have an alignment issue with your bowl of liquid. This will dictate what your acceptable deflection is. You don't need to ask us.
- Your liquid and container have a mass. Your bar has a spring rate. ω=sqrt(k/m). Your container full of liquid will bounce up and down and rotate at resonant frequency when it is bumped, or emptied and filled.
- ???
Do you really need to cantilever the thing? I crudely figure that tension/compression structures are around three orders of magnitude stiffer than cantilevers.RE: Acceptable deflection of a 25mm solid steel shaft
Stress, on the other hand, is how you determine whether your part will break. For parts under a static load, permanent deflection (yielding) is often the criteria for failure. For parts under a repeated load, the maximum stress is determined by the endurance limit of the material or a fatigue life analysis (cycles to failure).