simulating shaft runout

[koehler]

I have an application where by I have a lab mixer with a .312 dia stirrer shaft attached to the chuck. The shaft with a stirrer paddle at the other end extends down into a test tube in order to mix oil and water. The length of the shaft is 14 inches and it rotates at 1500 rpms. The axis of rotation at the extreme bottom must not deviate from the axis of rotation by more than .040. Question:
Can IV simulate a stirrer driven by a motor, stirring at 1500 rpms, and observe or calculate the runout on the shaft?

I have the unit designed and built and the shaft is running out more than the specifications require.

[Anonymous]

I supposed you could draw an elliptical (or eccentric circle) as the shaft
and rotate it, however this tolerance can be calculated by simple
mathematics. The RPM have nothing to do with the runout (assuming the shaft
is not bending due to centrifugal accelerations)

Have you measured the actual runout on the physical shaft?

--
Sean Dotson, PE
http://www.sdotson.com
Check the Inventor FAQ for most common questions
www.sdotson.com/faq.html
-----------------------------------------------------------------------
"koehler" wrote in message
news:f16d26d.-1@WebX.maYIadrTaRb...
> I have an application where by I have a lab mixer with a .312 dia stirrer
shaft attached to the chuck. The shaft with a stirrer paddle at the other
end extends down into a test tube in order to mix oil and water. The length
of the shaft is 14 inches and it rotates at 1500 rpms. The axis of rotation
at the extreme bottom must not deviate from the axis of rotation by more
than .040. Question:
> Can IV simulate a stirrer driven by a motor, stirring at 1500 rpms, and
observe or calculate the runout on the shaft?
> I have the unit designed and built and the shaft is running out more than
the specifications require.
>

[Anonymous]

No. This would require FEA (Finite Elemental Analysis) software. We use COSMOS
DesignSTAR. There are others. Many are integrated with Inventor, so that changes
to the geometry are updated in the FEA.

--
Dave Jacquemotte
Automation Designer

[Anonymous]

"The RPM have nothing to do with the runout (assuming the shaft is not
bending due to centrifugal accelerations)"

Now that I reread your question I think this *is* what you are looking for.
Dave is right. You'll need additional analysis software..

--
Sean Dotson, PE
http://www.sdotson.com
Check the Inventor FAQ for most common questions
www.sdotson.com/faq.html
-----------------------------------------------------------------------
"Sean Dotson" wrote in message
news:D6EEF09D403E42843797F5D2ABEC01B1@in.WebX.maYIadrTaRb...
> I supposed you could draw an elliptical (or eccentric circle) as the shaft
> and rotate it, however this tolerance can be calculated by simple
> mathematics. The RPM have nothing to do with the runout (assuming the
shaft
> is not bending due to centrifugal accelerations)
>
> Have you measured the actual runout on the physical shaft?
>
> --
> Sean Dotson, PE
> http://www.sdotson.com
> Check the Inventor FAQ for most common questions
> www.sdotson.com/faq.html
> -----------------------------------------------------------------------
> "koehler" wrote in message
> news:f16d26d.-1@WebX.maYIadrTaRb...
> > I have an application where by I have a lab mixer with a .312 dia
stirrer
> shaft attached to the chuck. The shaft with a stirrer paddle at the other
> end extends down into a test tube in order to mix oil and water. The
length
> of the shaft is 14 inches and it rotates at 1500 rpms. The axis of
rotation
> at the extreme bottom must not deviate from the axis of rotation by more
> than .040. Question:
> > Can IV simulate a stirrer driven by a motor, stirring at 1500 rpms, and
> observe or calculate the runout on the shaft?
> > I have the unit designed and built and the shaft is running out more
than
> the specifications require.
> >
>
>

[Anonymous]

Just some (not necessarily intelligent) ramblings.....

What's the runout at 2 RPM?

Is the test conducted in a fluid medium (loaded)?

Can the runout possibly be attributed to the drive mechanism?

Can it be attributed to balance?

So much depends on the shape of the part it's hard to as pertinent
questions...

Have you done any hand calcs for bending? What's it look like; screw, paddle,
fan?

I might be that it's difficult to get a meaningful FEA simulation. How
will it be loaded?

Good luck with it.
=========================

"koehler" wrote in message
news:f16d26d.-1@WebX.maYIadrTaRb...
> I have an application where by I have a lab mixer with a .312 dia stirrer
shaft attached to the chuck. The shaft with a stirrer paddle at the other end
extends down into a test tube in order to mix oil and water. The length of the
shaft is 14 inches and it rotates at 1500 rpms. The axis of rotation at the
extreme bottom must not deviate from the axis of rotation by more than .040.
Question:
> Can IV simulate a stirrer driven by a motor, stirring at 1500 rpms, and
observe or calculate the runout on the shaft?
> I have the unit designed and built and the shaft is running out more than
the specifications require.
>
>