Previous in Forum: Transformer Busduct   Next in Forum: Directional Protective Relay VS Reverse Power Relay
Close
Close
Close
12 comments
Commentator

Join Date: Nov 2007
Location: Calcutta
Posts: 79

Vacuum Sealing of a Furnace

09/27/2014 8:13 AM

I want to know how to vacuum seal the door of a a furnace of ,of Dimensions : 11ft X 11ft X 6ft (height) at 900;c inside temperature, the door being rise and fall type and being pressd by lock nuts for contact with matched machined part of the body,Generally at low temperature we use rubber gasket inside a groove to prevent leak . At 900;c what elastic material can be used ?

Login to Reply
Interested in this discussion?
You can "subscribe" to this discussion to be notified of new comments.
Click on the Subscribe menu at the top of the page.

Comments rated to be "almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, rate them!
Guru

Join Date: Dec 2007
Location: Haverhill, MA
Posts: 1135
Good Answers: 145
#1

Re: Vacuum sealing of a furnave

09/27/2014 10:09 AM

Water cool the door and mating flange. Use silicone rubber gasket.

__________________
The older I am, the better I used to be
Login to Reply Score 1 for Good Answer
Guru
United States - Member - New Member Engineering Fields - Power Engineering - New Member

Join Date: Sep 2006
Location: California, USA, where the Godless live next door to God.
Posts: 4643
Good Answers: 794
#2

Re: Vacuum sealing of a furnave

09/27/2014 11:45 AM

How does this relate to ELECTRICAL engineering?

__________________
** All I every really wanted to be, was... A LUMBERJACK!.**
Login to Reply
Guru

Join Date: Oct 2008
Posts: 42260
Good Answers: 1659
#5
In reply to #2

Re: Vacuum sealing of a furnave

09/27/2014 4:14 PM

It's an electric furnace?

Login to Reply
Guru
Hobbies - Fishing - Old Salt Hobbies - CNC - New Member United States - US - Statue of Liberty - New Member

Join Date: Mar 2007
Location: Rosedale, Maryland USA
Posts: 5198
Good Answers: 266
#3

Re: Vacuum sealing of a furnave

09/27/2014 11:46 AM

Most seals at that temperature are metal.

__________________
Life is not a journey to the grave with the intention of arriving in a pretty, pristine body but rather to come sliding in sideways, all used up and exclaiming, "Wow, what a ride!"
Login to Reply
Guru
Technical Fields - Technical Writing - New Member Engineering Fields - Piping Design Engineering - New Member

Join Date: May 2009
Location: Richland, WA, USA
Posts: 20872
Good Answers: 774
#4

Re: Vacuum sealing of a furnave

09/27/2014 1:00 PM

Metal tubing might make a suitable O-ring for this. See also FlexitallicTM gaskets.

__________________
In vino veritas; in cervisia carmen; in aqua E. coli.
Login to Reply
Guru
Engineering Fields - Electrical Engineering - Been there, done that. Engineering Fields - Control Engineering - New Member

Join Date: Dec 2008
Location: Long Island NY
Posts: 14878
Good Answers: 916
#6

Re: Vacuum Sealing of a Furnace

09/27/2014 9:18 PM

That is one very thick almost cubic door. Any vacuum chamber with a door this big would be an immense volume. The volumetric flow capability of the roughing, turbo and ion pumps on such a chamber would have to be equally immense to keep up with any nominal leakages a copper gasket could minimize.

I recommend that you place this enormous furnace door on Phobos. You probably won't need any gaskets there.

__________________
"Don't disturb my circles." translation of Archimedes last words
Login to Reply
Guru

Join Date: Apr 2011
Posts: 7885
Good Answers: 279
#7
In reply to #6

Re: Vacuum Sealing of a Furnace

09/27/2014 9:55 PM

At 900 C, copper might not be the best gasket material. The melting point is not too much higher, and even though the temperature might not ever get to the melting point, there could be problems associated with softening, corrosion, and outgassing.

__________________
Eternal vigilance is the price of knowledge. - George Santayana
Login to Reply
Power-User

Join Date: Jun 2007
Location: Center of the Known Industrial Universe - TUGGERAH 2259 - Australia
Posts: 257
Good Answers: 50
#8

Re: Vacuum Sealing of a Furnace

09/27/2014 10:34 PM

Wills Rings are commonly used in high temperature sealing service. Nuclear reactors, internal combustion engines, vacuum chambers are typical applications. These people quote a top temp of 850C but with tweaking they can go higher:

http://www.tss.trelleborg.com/global/en/products_2/staticseals/datailpages_staticseals/wills-rings-o.html

These are metal o-rings which can behave quite elastically if you choose the variety which is internally pressurized.
I have always enjoyed the pressurizing process for these metal o-rings. The selected tube is formed to the correct o-ring diameter, welded shut and neatly ground - but not before the ring is loaded with a measured weight of sodium azide explosive, depending on the internal o-ring void volume and the desired internal pressure.

Heat the ring, the sodium azide pops and there's your highly elastic, internally pressurized metal seal.
Mark Bingham
Relativity PL

Login to Reply
Power-User

Join Date: Jan 2008
Location: kuwait
Posts: 132
Good Answers: 2
#9

Re: Vacuum Sealing of a Furnace

09/28/2014 12:24 AM

copper gasket with the water cooling can be used here.the precisely machined male and female matching ring (cooling on the female side to keep the material in shape,and the same time the male part will expend with the heat to work as a tight seal.

__________________
love4everyone
Login to Reply Score 1 for Good Answer
Guru
Engineering Fields - Marine Engineering - New Member

Join Date: Aug 2007
Location: Australia
Posts: 1630
Good Answers: 19
#10

Re: Vacuum Sealing of a Furnace

09/28/2014 6:10 AM

Asbestos is still freely available in India, China, etc., why not use that.

I worked with asbestos for many many years at sea in my younger days, (we used to get covered in it, from head to toe......literally), neither I, nor at least two hundred others I worked with and knew reasonably well have suffered or died from any asbestos related diseases. several are no longer with us but have died from other non-related problems. Many of these one who have passed on, served on submarines (Australian "O" Class), and most had stomach or bowel cancer.

Just as a matter of I am still working full time in the maritime industry and I am closing, all too rapidly, onto 75...........and I am still working because I enjoy what I do.

__________________
TO BE. or NOT TO BE. That is the question!! The Bard
Login to Reply
Guru
United Kingdom - Member - New Member

Join Date: Aug 2010
Location: Resting under the Major Oak
Posts: 4348
Good Answers: 180
#11

Re: Vacuum Sealing of a Furnace

09/28/2014 8:56 PM

Look for Kerlane matting on Google. I've used it at above 900°C for sealing an annealing furnace.

__________________
The reports of my death are greatly exaggerated.
Login to Reply
Power-User

Join Date: Jul 2014
Location: Savannah, GA. The post office decided to change my address again.
Posts: 253
Good Answers: 19
#12

Re: Vacuum Sealing of a Furnace

09/29/2014 2:37 AM

We had two vacuum normalizing furnaces where we were making gas turbine engines for power generation, the mating surfaces were water cooled and used silicone O-ring material 20mm cross section, we regularly ran these furnaces to 2400° f and never had a failure.

An addendum: keep these seals clean and lubricated for long life.

__________________
Never seem more learned than the people you are with. Wear your learning like a pocket watch and keep it hidden. Do not pull it out to count the hours, but give the time when you are asked.(Lord Chesterfield)
Login to Reply
Login to Reply 12 comments
Interested in this discussion?
You can "subscribe" to this discussion to be notified of new comments.
Click on the Subscribe menu at the top of the page.

Comments rated to be "almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, rate them!
Copy to Clipboard

Users who posted comments:

gringogreg (1); JRaef (1); lyn (1); MOBI (1); ozzb (1); redfred (1); Relativity PL (1); sohail0110 (1); TonyS (1); Tornado (1); truth is not a compromise (1); Wrench twirler (1)

Previous in Forum: Transformer Busduct   Next in Forum: Directional Protective Relay VS Reverse Power Relay

Advertisement