What Flexible Seal Can Withstand 500°C and Allow Linear Motion?

[yanikomer]

I am working on a project where I need a high temperature sealing element. You can see the system in the attachment.

My moving object is moving linearly in a motion slot which is constructed on a sheet metal plate. But the surrounding temperature in this process is 500 C degree and there must be a flexible sealing element which does not let any particules or liquid material (oil etc.) to the behind of the sheet metal plate. As you see in the photo, I want the clearance between moving object and the sealing element as small as possible.

Does anyone know such a flexible sealing element that I can use in such a high temperature level and it also allows the motion of the moving object?

Thanks
yanikomer

 

[Danger]

I don't see any attachment, but my best guess based upon your typed post would be some sort of Teflon curtain. That's all that I can think of with the given information.

 

[nathanlee52]

Elastomeric sealing at high temperatures vs an oil is a delicate subject. Check out the Dupont Chemical Resistance Guide and you can get started there. As you'll see, volume swell, compression set, and other mech. properties will be represented as % losses. And those representations are fairly large brackets, like 10-15%. So, depending on the tolerance of your application, this may be a pain in the arse to work around. And of course, all the reference materials you'll find online clause themselves with lines like "performance subject to verification" or similar.

I can offer some tips, fill out these fields:

the Flowed media is:
the ambient temperature:
leakage spec:
flexible -- how flexible is flexible?:


Mode of sealing - dynamic, static, etc etc..

 

[yanikomer]

https://www.physicsforums.com/showthread.php?t=451309

You can see the attachment in this link.

ambient temperature is 500 C
leakage spec: liquids can leak but not solids
flexibility: it must allow the motion of the moving object

Many Thanks
yanikomer

 

[Danger]

Oh, wow... that is totally not what I was expecting. So your part travels along between the sealing surfaces like the slider on a zipper? It has to seal ahead and behind, and keep up with the motion in real-time.
Nathan is obviously very knowledgeable in this subject, so I defer to his expertise. I'm just going to ask a couple of questions in order to increase my own education, if you don't mind. One is how thick this barrier must be. By that I mean that if you are looking at it from the viewpoint shown in your picture, how "deep" into the page would it go? Also, what is the smallest particulate size of the solids that must be excluded? How fast does your slider have to move? Sorry if I'm being a pest, but you've got me curious.

 

[yanikomer]

Thank you Danger for your answer.

Actually the thickness of the seal element is about the heat transfer between the hot chamber and the beside of sealing element. This is also important but the first thing here is to find such a flexible sealing which allows the motion of the object there.

For example the width of the red moving object in the picture is about 10 mm and we can assume the witdh of the channel in the on the sheet metal as 20 mm.

Actually the sealing is used here just because not to let the oil particules to the behind of the sheet metal part. But after working on some kind of flexible sealing elements, i see that it is not so easy to achieve this kind of sealing. So that the smallest particule size is not so important right now. I worked on some mechanical sealing systems by the way. But this flexible one will be simple and cheaper if i find one.

The speed of the moving object is about 2.7 cm/s.

Thank you all.

 

[Danger]

I would recommend, seriously, that you consult with Brewnog and Fred Garvin. They both seem to have the most experience with sealing technology. I haven't seen Fred for a while, but Brewski is still here.
(Sort of reminds me of the old joke about the Inuit hunter who got trapped on an ice-floe with his snowmobile after he blew a seal... but I don't think that it's appropriate for PF Guidelines.)