Nees high temp, high tear resistance gasket material

[dextermech]

I am in need of a high tempterture (350 F max), high tear-resistant gasket material. The gaskets are used to face-seal the ends of 10 inch and 12 inch canisters under 28 inches of vacuum (so there is obviously considerable force on the gaskets, which are currently 3/16" 70 durometer silicone. The silicone is great for heat but it is not very tear resistant. The gaskets also must be bonded without worry of failure to 304 stainless disks. What is a good material for this? Right now I'm thinking butyl. Does anybody make a high temp urethane? Any help would be much appreciated!

 

[unclesyd]

There are any number of materials available for your service,Gylon,Chemreze,Kalrez.

Checkout the following sites.

http://www.garlock.net

http://www.gtweed.com/85256D3C0038D8DA/vwContentByKey/N25NLPR4971DMPJEN

http://www.kalrez.com/Header/index.asp

 

[MikeHalloran]

Why so thick?

I'm thinking a layer of RTV silicone, maybe .02" thick, bonded to the disks, would work better. Cure it against a smooth plate of TFE, or of steel or glass with a Saran film stretched over it for release, and shim the disk and the plate apart to control the thickness. Allow a couple of days for full cure.



Mike Halloran
NOT speaking for
DeAngelo Marine Exhaust Inc.
Ft. Lauderdale, FL, USA

 

[quark]

What about Spiral wound metallic gaskets with graphite? They are generally used with tongue and groove flanges but can work well for raised face flange joints also.

Here is a sample,

http://www.crgco.com/swgaskets.htm

 

[arto]

Don't forget Flexitallic -

http://www.flexitallic.com/documents/SpiralWoundCatalog.pdf

also - check your gasket seating/bolting per ASME Sec VIII Div 1 App. 2 [even though it's under vacuum, it still needs to be eated to achieve a pressure seal]also check "scalloping" between bolts if it's a thin cover. [usually a "pi" bolt spacing ~3-1/8" inches works well, with plate thickness per UG-34]