Vince Pitelka on wed 1 feb 06
Paul Herman wrote:
> I believe the term "K23" is a different reference than "PCE". PCE
> refers to the pyrometric cone equivalent (the cone at which the
> bricks material, if made into a cone, would bend). K23 I still
> believe refers to service temperature in degrees F. So I think you
> are trying to make a connection where there is none.
Tht's correct. The references "K23," "K26," etc. used for IFB refer
specifically to a 2300 Fahrenheit or 2600 Fahrenheit operating temperature,
and have nothing to do with pyrometric cone equivalents.
- 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/
Ivor and Olive Lewis on fri 3 feb 06
Dear Vince Pitelka,=20
Thank you for that. I was confused by that Peter Meenly report on salt =
glaze.
Do you know how this convention originated ?
Best regards,
Ivor
Craig Clark on fri 3 feb 06
When I was purchasing bricks, both hard and soft, I was told by the
supplier (AP Green at that time) that the K+number reference refered to
the Farenhieht temperature at which the brick was rated for a "continous
duty" cycle. This translates to the Farenheit temp at which the brick
can be fired and held over the life of the kiln. Temps higher than the
rated one, especially over extended periods of time such as soaking at
the high end, lead to a rapid degradation of the brick. I was never told
of any relationship that the brick ratings have to cones, but I imagine
one could be deduced.
I've never read Fourneir but will see if I can order a copy of the
text through Interlibrary loan. I agree, I cannot understand the rating
of a fire brick with an eq uivalency of 3300 degrees F, at least not
one composed of what "normal" firebricks are made. However, I suspect
that there are indeed esoterics which when combined in a certain manner
will yeild refractory composites in brick form which will can indeed
withstand that type of temperature.
Here are a few links which may be of
interest......http://www.cotronics.com/vo/cotr/cm_castable.htm
http://www.stormingmedia.us/53/5399/A539904.html
Here is one talking about Zirconia based refractories with duty
ratings in excess of 2100 Celcuis...
http://www.dynacer.com/refractories.htm
Hope this helps
Craig Dunn Clark
619 East 11 1/2 St.
Houston, Texas 77008
(713)861-2083
mudman@hal-pc.org
I'm not understanding what Vince Pitelka wrote:
> Paul Herman wrote:
>
>> I believe the term "K23" is a different reference than "PCE". PCE
>> refers to the pyrometric cone equivalent (the cone at which the
>> bricks material, if made into a cone, would bend). K23 I still
>> believe refers to service temperature in degrees F. So I think you
>> are trying to make a connection where there is none.
>
>
> Tht's correct. The references "K23," "K26," etc. used for IFB refer
> specifically to a 2300 Fahrenheit or 2600 Fahrenheit operating
> temperature,
> and have nothing to do with pyrometric cone equivalents.
> - 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/
>
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Vince Pitelka on fri 3 feb 06
Ivor wrote:
"Thank you for that. I was confused by that Peter Meenly report on salt
glaze.
Do you know how this convention originated ?"
Dear Ivor -
I don't know where it came from. The first time I bought IFB was in the mid
1970s, and this convention was already standard, so it seems to be a
long-time reference for IFB. It is interesting that they do not use the
same convention with hardbrick, generally referring to them as high-duty,
super-high-duy, etc. The manufacturer can always provide the maximum
working temperature.
- 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/
Paul Herman on sat 4 feb 06
Mark,
I certainly would use K23 for a cone 7 firing. In fact, I use them
routinely for cone 11 firings. That said, I've heard there is one
brand of k23 brick that does not hold up well to cone 10-11. Which
brand I can't tell you. Perhaps someone else can?
Paul Herman
Great Basin Pottery
Doyle, California US
http://greatbasinpottery.com
On Feb 4, 2006, at 2:33 PM, Mark Tigges wrote:
>>
>>
>>> Does a lower temperature IFB have a greater insulating value than
>>> one of a
>>> higher temperature rating?
>>>
>>
>> Yes. The lower rated IFB is less dense, and a better insulator.
>> Also cheaper. It makes sense to build with graded layers, putting
>> lower rated bricks on the outside.
>>
>>
>
> This is not something I realized, but seems obvious now somehow. I
> just presumed that I should use K26, but if you were building a kiln
> which was never going to go above cone 6.5 / 7, it seems that K23
> would definitely be preferable.
>
> Right?
Edouard Bastarache Inc. on sat 4 feb 06
Mark,
if you are to fire in the vicinity of 2300 F and use K26 IFBs,
they will behave as hard bricks and the kiln will be a lot
more expensive to fire.
Later,
"Ils sont fous ces quebecois"
"They are insane these quebekers"
"Están locos estos quebequeses"
Edouard Bastarache
Irreductible Quebecois
Indomitable Quebeker
Sorel-Tracy
Quebec
edouardb@sorel-tracy.qc.ca
www.sorel-tracy.qc.ca/~edouardb/Welcome.html
http://perso.wanadoo.fr/smart2000/index.htm
http://www.flickr.com/photos/potier/
http://substitutions.blogspot.com/
http://retrodemonstration.blogspot.com/
William & Susan Schran User on sat 4 feb 06
On 2/3/06 2:17 PM, "Craig Clark" wrote:
> When I was purchasing bricks, both hard and soft, I was told by the
> supplier (AP Green at that time) that the K+number reference refered to
> the Farenhieht temperature at which the brick was rated for a "continous
> duty" cycle.
I would think "continuous duty" is key in defining a temperature rating of a
brick. As with most of the materials potters use, a vast majority of bricks
are used by industry. I would expect many kilns used in commercial
applications are continuous duty - firing all the time, such as tunnel
kilns.
Industry would need to know the rating based on continuous duty, not
periodic firings.
Does a lower temperature IFB have a greater insulating value than one of a
higher temperature rating? Say K23 VS K26. Perhaps K20 bricks would be a
better choice for raku kilns.
-- William "Bill" Schran
Fredericksburg, Virginia
wschran@cox.net
wschran@nvcc.edu
Paul Herman on sat 4 feb 06
Bill,
You asked:
> Does a lower temperature IFB have a greater insulating value than
> one of a
> higher temperature rating?
Yes. The lower rated IFB is less dense, and a better insulator.
Also cheaper. It makes sense to build with graded layers, putting
lower rated bricks on the outside.
best,
Paul Herman
Great Basin Pottery
Doyle, California US
http://greatbasinpottery.com
Mark Tigges on sat 4 feb 06
On Sat, Feb 04, 2006 at 01:02:49PM -0800, Paul Herman wrote:
> Bill,
>
> You asked:
>
> >Does a lower temperature IFB have a greater insulating value than
> >one of a
> >higher temperature rating?
>
> Yes. The lower rated IFB is less dense, and a better insulator.
> Also cheaper. It makes sense to build with graded layers, putting
> lower rated bricks on the outside.
>
This is not something I realized, but seems obvious now somehow. I
just presumed that I should use K26, but if you were building a kiln
which was never going to go above cone 6.5 / 7, it seems that K23
would definitely be preferable.
Right?
Mark.
Ivor and Olive Lewis on sat 4 feb 06
Dear Craig Clark=20
Thank you for your note. See also Fournier, page 82, entry, "Firebrick". =
This may or may not mean Insulating Firebrick but he says "Firebrick: A =
refractory brick, generally made from fireclay and grog. Industrial =
Firebricks are given P.C.E. ratings" and follows up with examples.
Best regards,
Ivor
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