Extreme Temperature Rotary Seal 3

[farzadinjast]

Hi all,

I am looking for a sealing solution for isolating a pressurized air cavity (75 PSI) from the outside. A shaft is to come out of the cavity and it should be sealed to prevent the air from exiting. The rotation speed and duty cycle is low (10 RPM). The temperature of the cavity is high (1200 F) and it is the restriction for using the conventional seals. Please help me on selecting a product which can handle this situation.

 

[Chpal1984]

1200 F is pretty hot for just fitting a mechanical seal, especially since your low rpm limits the effectiveness of a plan 21/23. Have you considered a gland packing solution?

 

[farzadinjast]

Thank you for the reply.
No I have not think about that. It may seem very elementary question but it would help me a lot. can you please give me some hints on packing? Can it handle rotation or it is just for static sealing?

 

[sreid]

Can you use a magnetic coupling between shafts inside and outside the pressurized chamber?

https://en.wikipedia.org/wiki/Magnetic_coupling

 

[gyaneshwarp]

It is possible to solve your problem by providing a double seal.
Do you have enough space oto mount a double seal.between inboard seal and vessel cavity long throat bush can be given to reduce temperature in seal area.
I suggest that please provide shaft diameter and axial space available.

 

[Chpal1984]

You can definitely use gland packing on rotating shafts (especially as slow as 10rpm). I'm not an expert, these are a decent supplier

http://www.aesseal.co.uk/en/product/gland-packing.

I would start by emailing them. This is more of a budget solution than the previous 2 posts, however I'm told gland packing can be a very good solution if used correctly

 

[Rustam1]

There are seals from thermo-expanded graphite. Operating temperatures of 600 C or higher, are intended for both moving and fixed joints.
Recommend to turn to specialized companies for the production of such seals: "SGL-Polycarbon", "SIGRAFLEX", "Union Carbide"(GRAFOIL).

 

[farzadinjast]

Thank you very much dear fellows. I will follow your hints to find the best solution.