MudFire - Luba & Erik on sat 9 dec 06
Does anyone have thoughts on optimal alumina/silica content of IFB that =
will be used in a soda vapor kiln? Does 35% alumina content seem high =
enough? Is it worth paying double (per brick) for a 46% alumina content =
in this scenario? Does the trace presence of iron (1%) seem like a bad =
idea? I've been trying to download Thermal Ceramics chemical analysis =
for K23 and K26 but their site freezes in the process. Crashed the =
computer a bunch of times... does anyone happen to have the printout =
handy?
Thanks again!! You guys rock!
Luba=20
MudFire Clayworks & Gallery
Open Studio * Workshops * Exhibits
175 Laredo Dr, Decatur, GA 30030
404-377-8033
www.mudfire.com
jonathan edward byler on sun 10 dec 06
call them and they will fax you the data sheets.
-jon
On Dec 9, 2006, at 9:28 PM, MudFire - Luba & Erik wrote:
> Does anyone have thoughts on optimal alumina/silica content of IFB
> that will be used in a soda vapor kiln? Does 35% alumina content
> seem high enough? Is it worth paying double (per brick) for a 46%
> alumina content in this scenario? Does the trace presence of iron
> (1%) seem like a bad idea? I've been trying to download Thermal
> Ceramics chemical analysis for K23 and K26 but their site freezes
> in the process. Crashed the computer a bunch of times... does
> anyone happen to have the printout handy?
>
> Thanks again!! You guys rock!
> Luba
>
> MudFire Clayworks & Gallery
> Open Studio * Workshops * Exhibits
>
> 175 Laredo Dr, Decatur, GA 30030
> 404-377-8033
> www.mudfire.com
>
> ______________________________________________________________________
> ________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
Ivor and Olive Lewis on tue 12 dec 06
Dear Luba & Erik=20
I have two answers.
The first starts, "It all depends....on the individual chemistries and =
the reactions that may or may not happen at your chosen firing =
temperature"
The second is the rule of thumb that if the reaction leading to a glaze =
takes place between either Sodium Carbonate or Sodium Chloride and =
Silicon dioxide but not with Iron oxide or Aluminium oxide, then forget =
about the Iron oxide and have as high an Alumina fraction as possible..
Best regards,
Ivor Lewis.
Redhill,
South Australia.
Vince Pitelka on tue 12 dec 06
Ivor Lewis wrote:
"The second is the rule of thumb that if the reaction leading to a glaze
takes place between either Sodium Carbonate or Sodium Chloride and Silicon
dioxide but not with Iron oxide or Aluminium oxide, then forget about the
Iron oxide and have as high an Alumina fraction as possible."
Ivor -
I'm a little confused here. I hope I haven't misunderstood this thread.
Isn't Luba interested in building a soda kiln? It has already been
established by some of the leading soda and salt-firers in the US that
high-alumina brick are completely inappropriate for salt and soda kiln
hotface applications. The brick are so refractory that they remain porous
and open, and sodium vapors penetrate the brick, causing it to break down
internally. The result is swelling and spalling, and it happens amazingly
fast.
At the Craft Center, at a time when we couldn't afford any other built, we
received a large donation of AP Green "Kruzite" high-alumina brick, and
built a salt kiln and a large wood kiln. The wood kiln is still going
strong, but the salt kiln had to be demolished and rebuilt three years
later. It was terrible to see what happened with those high-alumina brick
in the hotface. They swelled up and the whole kiln moved around.
As Hank Murrow has clearly stated on a number of occasions, he has had
experience with a salt kiln constructed with high-silica brick that gave
good service for decades.
For all salt and soda kiln hotface applications, stay away from high-alumina
brick.
- Vince
Vince Pitelka
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111
vpitelka@dtccom.net, wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/
Edouard Bastarache Inc. on tue 12 dec 06
Hello Ivor,
there are "high alumina" firebrick for foundries.
I have some and use them as kiln posts.
Has anybody use them for the inside of salt/soda
kilns?
Later,
----- Original Message -----
From: "Ivor and Olive Lewis"
To:
Sent: Monday, December 11, 2006 11:24 PM
Subject: more on soft bricks and alumina content
Dear Luba & Erik
I have two answers.
The first starts, "It all depends....on the
individual chemistries and the reactions that may
or may not happen at your chosen firing
temperature"
The second is the rule of thumb that if the
reaction leading to a glaze takes place between
either Sodium Carbonate or Sodium Chloride and
Silicon dioxide but not with Iron oxide or
Aluminium oxide, then forget about the Iron oxide
and have as high an Alumina fraction as possible..
Best regards,
Ivor Lewis.
Redhill,
South Australia.
______________________________________________________________________________
Send postings to clayart@lsv.ceramics.org
You may look at the archives for the list or
change your subscription
settings from http://www.ceramics.org/clayart/
Moderator of the list is Mel Jacobson who may be
reached at melpots@pclink.com.
Vince Pitelka on wed 13 dec 06
Edouard wrote:
> there are "high alumina" firebrick for foundries.
> I have some and use them as kiln posts.
> Has anybody use them for the inside of salt/soda
> kilns?
Edouard -
I have discussed this several times on Clayart, and did again in a reply to
one of Ivor's posts today. Perhaps if one could completely seal the surface
and the joints in order to prevent sodium vapor from penetrating the brick,
high-alumina brick could work, but that would pretty much eliminate the
whole point of using them.
When AP Green sold out to Harbison Walker, they shut down all of their
manufacturing plants and regional warehouses, and when that happened, much
of the stock refractories were up for grabs, available for free to colleges
and universities. For us in central Tennessee, the closest big
manufacturing plant and warehouse was in Bessemer, Alabama, just outside
Birmingham. So, of course almost all of the refractories that they
manufactured and stocked were for the steel industry - high-alumina
hardbrick. At the time, we really needed to rebuild our salt kiln, and it
seemed to me that high-alumina brick would be just the thing for a salt
kiln, since alumina resists salt attack and deposition. So we hauled four
or five dumptruck-loads of brand new Kruzite hardbrick back to the Craft
Center. Tennessee higher education was experiencing lean times then, and we
had no money at all for kiln construction. We got a local steel supplier to
donate all of the steel we needed, and Steve Robison, Kathy Guss, and I,
along with my students, put a great deal of time and energy into building a
beautiful salt kiln out of this brick.
But as I explained in the reply to Ivor, it was terrible to see what
happened to that kiln over just a few years. The sodium vapor penetrated
the porous super-refractory brick, causing it to swell and shift internally,
and to spall and peel on the hotface surface. We finally had to demolish
the kiln, and the next time we built with AP Green high-duty and super-duty
Empires and Clippers, and they have held up well. That's kiln seen heavy
use for about five years now, and we should get at least a few more years
out of it.
- Vince
Vince Pitelka
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111
vpitelka@dtccom.net, wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/
jonathan edward byler on wed 13 dec 06
vince,
thanks for sharing this info with us. The more information that we
have, the easier it is to make informed decisions, and hopefully
fewer mistakes.
-jon
On Dec 13, 2006, at 1:07 AM, Vince Pitelka wrote:
> Edouard wrote:
>> there are "high alumina" firebrick for foundries.
>> I have some and use them as kiln posts.
>> Has anybody use them for the inside of salt/soda
>> kilns?
>
> Edouard -
> I have discussed this several times on Clayart, and did again in a
> reply to
> one of Ivor's posts today. Perhaps if one could completely seal
> the surface
> and the joints in order to prevent sodium vapor from penetrating
> the brick,
> high-alumina brick could work, but that would pretty much eliminate
> the
> whole point of using them.
>
> When AP Green sold out to Harbison Walker, they shut down all of their
> manufacturing plants and regional warehouses, and when that
> happened, much
> of the stock refractories were up for grabs, available for free to
> colleges
> and universities. For us in central Tennessee, the closest big
> manufacturing plant and warehouse was in Bessemer, Alabama, just
> outside
> Birmingham. So, of course almost all of the refractories that they
> manufactured and stocked were for the steel industry - high-alumina
> hardbrick. At the time, we really needed to rebuild our salt
> kiln, and it
> seemed to me that high-alumina brick would be just the thing for a
> salt
> kiln, since alumina resists salt attack and deposition. So we
> hauled four
> or five dumptruck-loads of brand new Kruzite hardbrick back to the
> Craft
> Center. Tennessee higher education was experiencing lean times
> then, and we
> had no money at all for kiln construction. We got a local steel
> supplier to
> donate all of the steel we needed, and Steve Robison, Kathy Guss,
> and I,
> along with my students, put a great deal of time and energy into
> building a
> beautiful salt kiln out of this brick.
>
> But as I explained in the reply to Ivor, it was terrible to see what
> happened to that kiln over just a few years. The sodium vapor
> penetrated
> the porous super-refractory brick, causing it to swell and shift
> internally,
> and to spall and peel on the hotface surface. We finally had to
> demolish
> the kiln, and the next time we built with AP Green high-duty and
> super-duty
> Empires and Clippers, and they have held up well. That's kiln seen
> heavy
> use for about five years now, and we should get at least a few more
> years
> out of it.
> - Vince
>
> Vince Pitelka
> Appalachian Center for Craft, Tennessee Technological University
> Smithville TN 37166, 615/597-6801 x111
> vpitelka@dtccom.net, wpitelka@tntech.edu
> http://iweb.tntech.edu/wpitelka/
> http://www.tntech.edu/craftcenter/
>
> ______________________________________________________________________
> ________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
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