What seals to use on a gasifier

Whatever i build, or whatever i would love to build, always comes the point to ad a seal at a certain place.

Reading thru most of the topics, the question arises many times “what seals to use”.

From my experience, most of the troubles in a normal working gasifier start with a leaking seal in some form.

As i like to build and develop easy to use / maintain gasifiers my knowledge is somehow “biased” on what should be used or done.

But i am eager to learn from others and share my own, therefore i start this topic…

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I have found that rubber works well for a lot of applications on a gasifier most places you need to seal are not crazy hot.

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I use strictly ceramic on anything above 200*f and then move to a stick on rubber stripping after this. On my blower motor I use silicone but this is pretty much the only place I use that messy stuff. I use the black industrial stuff that is stronger than the bolts holding this blower on!!. lol

I am no longer am too concerned with leaks. If you are pulling so hard that you are seeping through your seals you have bigger problems than a leaky seal. Get the clog fixed and your seal will probably be just fine. lol

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Can you post some spec or info about that product you use ? it might help some others to solve their trouble shooting.

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Here is a link to McMaster Carr high temp adhesive backed seal tape. Ive been using this for years it is the only way to go. If you are leaking past these seals you have something else wrong causing the leak. :slight_smile:

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i took this picture from Bobmac to use as example;

Stove rope in any kind of form will work, untill…

  • High temperature dry’s out the seal and cracks ( to define what temperature and what seal is in use )
  • The frequent open / close operations will rend the seal into a hard, non soft cushioning surface
  • Ash or carbon deposits, if not proper cleaned , damage the seal capacity…

If i use this kind of seal, i apply some copper paste on the surface, making sure the surface is only used with little pressure applied ( overbolting on seals lead to early damage / leaking )

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Yup, I on my new door design I have seen a failure as described. It will get hardened and then brittle and fall apart. This area where my door seals is not supposed to get very hot. When you see the paint turn white this is an indication of the seal failure. A leak to begin will cause the seal to fail prematurely. I will have to try adding your method for added longevity.

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for low temperature seals i am testing with molding silicone, can be poored in any shape or form…

https://www.amazon.com/s?k=silicone+for+mold+making&hvadid=375992787316&hvdev=c&hvlocphy=9074442&hvnetw=g&hvpos=1t2&hvqmt=b&hvrand=8892755873850507410&hvtargid=kwd-297818187535&tag=hydglogoo-20&ref=pd_sl_54cf0wzrxi_b

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I forgot, I am using a bulb seal now as well. I use this on my hopper lids and my blower housing. This will not work on most traditional system where the hopper can get hot when ran low. On my systems the hopper is always cold, so I can get away with this type of seal now. Makes the hopper lid construction a ton easier; bulb seal is far superior to anything else Ive tried. .

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For fill lids on my charcoal rigs I use a tire inner tube.

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What is a bulb seal?

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Its a press on weather stripping with crush bulb seal built into it.

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