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kiln expansion

updated fri 12 jun 98

 

EDWIN GOULD on wed 10 jun 98

for a down draft, 20 cu. ft. cone 10 firing......the guy who is going to
build the steel frame for the door wants to know WHAT AMOUNT OF BRICK
EXPANSION WE SHOULD EXPECT WHEN WE FIRE????. Is it a concern? We have
springs at each corner of the steel frame to permit the 10 inch high
sprung arch. THANKS FOR ALL THE HELP IN THE PAST; YOUR COLLECTIVE
SUGGESTIONS HAVE BEEN A REAL BOOST TO THE TWO OF US NOVICES.
ED

Cameron Harman on thu 11 jun 98

The expansion of the arch is another thing, but the expansion of
walls should be contained by a fixed wall. All the interior walls
of a rectangular kiln should contain expansion joints where the
brick can slip together as they expand and slip apart as they
shrink.

The size of the expansion joint can be calculated as follows:
length of wall in inches times the temperature rise in degrees
Farenheit times 0.0000063. The answer is in inches. As an example
take a 40 inch long wall fired to 2180 F. The expansion at peak
temperature would be one-half inch (0.5"), so a one-haf inch joint
should be provided in this case. The size of the inside wall would
still be 40 inches, but with 39.5 inches of brick and 1/2" of
expansion joint.

I know that this may be confusing, so email your questions and we
can talk about it.

Regards,
Cameron Harman

Vince Pitelka on thu 11 jun 98

>for a down draft, 20 cu. ft. cone 10 firing......the guy who is going to
>build the steel frame for the door wants to know WHAT AMOUNT OF BRICK
>EXPANSION WE SHOULD EXPECT WHEN WE FIRE????. Is it a concern?
Ed -
I have never left any expansion space within the door frame, but my doors
have always been softbrick or fiber. Softbrick seems to take care of
itself, without the need for any expansion spaces.
- Vince

Vince Pitelka - vpitelka@DeKalb.net
Home 615/597-5376, work 615/597-6801, fax 615/597-6803
Appalachian Center for Crafts
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166