Radial seal that also permits axial movement

[spggodd]

Apologies for the repost but I wasn't getting much response in my Seal forum..
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Hey all,

I'm wondering if any of you have experience with anything that can seal a shaft travelling at around 3000rpm but also must allow +/-10mm axial shaft movement?
Originally I was going to use a basic radial lip seal but I'm not sure if the lip will just bend back on its self when the shaft is axially moved.

Cheers
Steve

 

[TheTick]

http://www2.chicago-rawhide.com/

 

[spggodd]

I have been reading in the SKF mannual for thier lip type seals and it seems that they allow axial movement, providing the surface finish and quality of the shaft is the same along the travel distance.

 

[tbuelna]

What is the shaft diameter? What is the pressure delta across the seal interface? What are the temperatures involved? What fluids/environments are the seal exposed to? Can you tolerate any amount of leakage past the seal, both during operation or when idle?

A conventional radial lip seal will tolerate axial displacement of the shaft as long as there is adequate sealing surface provided on the shaft. But most elastomer lip seals are not suitable for surface speeds much beyond about 3000fpm, or more than very modest pressure differentials.

Hope that helps.
Terry

 

[Tmoose]

Like tbuelna said surface feet per minute for rotation and translation must be considered right now, but only along with dp, temp, fluid, etc.
Lip seals //might// work.
O-rings //might// work
packing glands //might// work.
A simple non-contact labyrinth //might// work.

 

[spggodd]

Hi guysm, thanks for the advice.

Shaft diameter is 70mm and 100mm (2 different locations), pressure delta is minimal. Temperatures are likely to be up to 120 DegC. Fluid in use will most likely be ISO46 type oil.

Minimal leakage is required, although I appreciate the seal will need to be wet in order to work correctly.

It looks like from what you and SKF are saying, I can have axial movement on the shaft providing the surface finish is constant across the moving distance.

 

[Tmoose]

100mm and 3000 rpm

how long do you want the seal to last?
What is the bearing arrangement?
Lip seals require the shaft to remain nicely centered in the seal, unless crafty floating seal housing are use