Elastic Hot Gas Seal - Up to 1200°F & 1 Atm Pressure

[Aero Stud]

Hello people

Again I need some help...:shy:
I'm looking for a type of cloth that can be used to seal a gas at up to 700 degrees C (about 1200 F) and a pressure difference of up to 1 atmosphere.

Just to explain a bit more, I want to seal gas between two sections of a jet engine nozzle that can move a short ditance with respect to each other. The cloth is not directly exposed to the jet, just seals the whole thing on the outside, so the gas is mostly static in the emmidiate sealed volume ouside the nozzle, and pressure difference is actually probably less than even half an atmosphere (1 is just to be safe for now).

I found some fiberglass materials so far but I still don't know how well they can handle pressure or seal hot gas. I'll keep looking.

Thank you

 

[Q_Goest]

Hi Aero,
It sounds like you want a small amount of movement between the two parts you're sealing. Have you looked into Grafoil? It's commonly used on very high temperature valves, and can be used both as a static and dynamic seal. One manufacturer is UCAR Carbon, but I believe it's sold primarily through distributors:
http://www.usseal.com/Graphite.htm
http://www.grafoilsales.com/

You might also try posting your question at the engineering tips forum:
http://www.eng-tips.com/threadminder.cfm?pid=819

 

[Aero Stud]

Thank you again Q_Goest. :)

I looked at Grafoil, but it seems to mostly be used for O-rings. Anyway, many of these specifications are so specific that it's difficult to understand what exactly you're supposed to use these materials for, unless you have a pic.

Anyway, I think I found something:
http://www.jameswalker.biz/group/categories/expansion_joints.html

Hope it works.

 

[FredGarvin]

Depending on the surrounding geometry you may have to go with a bellows type of a seal.

 

[Aero Stud]

That's exactly what I want to avoid. I'm supposed to be an aerospace engineer dealing with stuff that's supposed to fly not an armoured tank engineer...

 

[FredGarvin]

That's exactly what I want to avoid. I'm supposed to be an aerospace engineer dealing with stuff that's supposed to fly not an armoured tank engineer...

I hate to break it to you, but bellows seals are on a lot of flying engines.

 

[Aero Stud]

I didn't mean that, I meant I want to save weight as much as possible and what I found looks promisng. Thanks.