Water jacket seal for spin casting machine

[Barry1961]

I have a customer with a centrifugal spin casting operation that is having trouble with the seals on the water jacket wearing out every 3 or 4 months. The current seals are made of rubber. The customer is looking for ideas on something that might last longer than the rubber seals and is willing to build a housing to fit. The largest ID would be 26.5” with OD being variable. They were thinking of a sealed bearing but have not had any luck finding one that could take the pressure.

100 psi water
150 degree F
200 rpm??
200lb load?

The cooling water comes in around 80 degrees and can leave as hot as 150 degrees. They can have pressure surges up to 100 psi. I am guessing at rpm and the weight of sleeve housing where water would come in.

I would guess part of the problem is that the surface the seal is riding on is not as smooth as it should be. If this could be a two or three part seal where both surfaces are removable it would help. Sort of like a really big speedy sleeve with matching seal.

Any ideas?

Barry1961

 

[sreid]

Perhaps you could try adding a soluable oil to the cooling water. Water alone has really bad lubricity.

 

[tbuelna]

barry1961,

Coolant pumps, for things like internal combustion engines, typically use carbon face seals.

Regards,
Terry

 

[Cockroach]

You don't have a particularly aggressive environment for soft seated seals. Try increasing the elastomer durometer to 90 or 95. Also, change the compound matrix material to something a little more favorable to that environment.

Neither of these properties, durometer and material, have been mentioned in your posting. In general, ethylene propylene is rated for water service, but you need to be aware of the dissolved carbonates which may be detrimental to elastomer performance over time. Lubrication is another design advantage, I have often had an oil reservoir apply trace amounts of fluid to keep wear rates down between the rotating shaft and seal itself.

You should be getting lifetimes in the order of years, not months. Check the compression and stretch of the seal itself, perhaps this is a problem limiting lifetime(s).

Good luck

Kenneth J Hueston, PEng
Principal
Sturni-Hueston Engineering Inc
Edmonton, Alberta Canada