Gaskets 2

[mielke]

I don't have much experience with gaskets and was hoping to get a second opinion from people here.

We have a pressure vessel with a rectangular flange (10"x30" apprx) and operating conditions of 100psi and 800F continous service. The gas used is going to be diesel exhaust (after catalytic converter and filters) We prefer to not use graphite based gaskets.

Any suggetsions or opinions on what gaskets would be best with the lowest price will be helpful.

 

[SnTMan]

Why not ask the gasket makers?

Regards,

Mike

 

[mielke]

"I don't have much experience with gaskets and was hoping to get a second opinion from people here."

I did.

"Any suggetsions or opinions...will be helpful."

 

[bcd]

Continuous exposure at +800 F really limits your options to Graphite or Carbon fiber materials. Only other option is metal seals, but since your joint is not a round shape, you can pretty much rule out a reasonable cost metal seal as well. Graphite and Carbon are your options.

 

[SnTMan]

mielke, do I interpret that you did ask the gasket makers? What did they say?

Leaving out graphite, they should have a few composition materials usable at your temperature. I doubt anybody will sell asbestos anymore.

They can also perhaps consider the joint design when recommending a gasket. Narrow ring, full face?

How tight a joint are you looking for?

Many factors involved...

Regards,

Mike

 

[mielke]

thanks bcd, any thoughts on ceramic board gaskets

 

[mielke]

also like i said i don't have much experience on this, would anybody have an idea why someone would not prefer a graphite gasket for my original specs. (fyi its a stainless steel pressure vessel)

 

[SNORGY]

It could be that the service might have a propensity to pull graphite out of the gasket. I ran into a situation like that years ago during flushing and commissioning a compressor lube oil skid where graphite (or flaking graphoil) was in the Flexitallic filler (gray stripe). It took about a week of lube oil flushing to achieve acceptably clean milk pads, which were collecting the filler material being washed out of the gaskets. Shortly after that experience the Client's specifications were changed to go to different filler materials in lube oil service.

Regards,

SNORGY.

 

[unclesyd]

You are approaching the upper limit for graphite or Grafoil in oxidizing media. If not oxidizing and you use Grafoil or Graphite make sure you use a metal reinforced material, like Inconel mesh.


If your media is oxidizing you should go with a fibrous ceramic material.

 

[tbuelna]

mielke,

If you only need one gasket, and if your mating flanges are stiff and flat, I'd recommend making one by wire EDM of annealed copper sheet. There are lots of aftermarket automotive gasket makers that can do this for you.

If you flanges are not flat and/or stiff enough to seal with soft solid copper sheet, then ask for copper sandwich material. Depending upon how complex your flange shape is, you might be able to even get a sandwich material gasket made without tooling charges.

Either material will take your temperatures and pressures.

Good luck.
Terry