High speed shaft coupling

[winflex]

I am in the process of designing a hydrostatic thrust bearing test stand for a small hydraulic turbine. The turbine's shaft will be driven with a VFD controlled spindle motor at roughly 25000RPM. Power should be less than 1kW.
I am looking for a shaft coupling that can handle this type of speed as well as some axial travel (as the thickness of the hydrostatic lubrication cushion changes by a few thousands of an inch).
Some helical flexible beam couplings or jaw type couplings are advertised to be able to handle this sort of speed. Does anyone have experience with coupling shafts at this speed?
I am certainly planning on placing a rigid safety cage around the coupling.

Regards,

- Felix

 

[flexibox]

this sounds like a small shaft diameter. what is the Distance between shaft ends? Have you considered membrane type couplings? They may not be available in your size. helical flexible beam couplings seem to have a speed limit of 6000RPM. Check their limits. no mater which coupling you use it should be dynamically balanced I would use G1.0 and match weigh the bolts.

 

[Pumpsonly]

Try the below link.

http://www.rwcouplings.com/miniature_couplings/index.html

 

[winflex]

The distance between the shaft ends can be any value and I'm designing the fixture around the coupling. Anticipated shaft diameter will be 0.25 to 0.5 inches.