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kiln car deck...whats goin' on...

updated sat 30 nov 96


Jonathan Kaplan on fri 8 nov 96

So I have received a few replies from the list about the structure of
various car decks, or car tops, and I'll now post what has ocurred with
mine, and give a brief description and hopefully those of you who have some
other experiences can share your input.

Car dimensions....steel shell 1/4" angle iron with steel plate. lots of
reinforcement underneath.
27.5" width 45"length 4 wheels

Refractories:........ (reading from bottom to hot face)1/2"refractory board

1 layer 2300 degree IFB 2.5"h

1 layer 2600 degree IFB 4.5"h

total insulation 7.5" IFB all mortared

Shelf support-Ferro cordierite tubes 3"OD x 2"ID 12" long resting on the
steel base plate of
the car extending through the IFB in 3.5" sized
holes. Differential packed with
fiber and the tubes are packed with fiber. Ferro caps
4" dia on top of tubes.
A wonderful strong system, very stable.

Shelf Size reading from rear of car-(all shelves are 14 x 28 x 1 alcorit
rear wall
28" x 28" with
four props
14" x 28" with 3 props

There is a continuous fiber expansion joint around the interior perimeter
of the steel of the car of 3/4 inch or so.

The problem is that the bricks have huge cracks in three places, none of
which correspond to the large 3.5" holes for the cordierite tubes, which is
where I expected them to be. The cracks run left to right, and front to
back. Plus, the IFB deck is now rising up and there is a definite curve in
its surface. This has been the second rebuild on the car. There are no
minute fractures or what I would call stress cracks in the car top.

I am perplexed. I accounted for expansion in the brick with fiber in what I
believe to be critical areas--the perimeter along the steel shell and the
differential of the 3" cordierite tubes and their matching holes in the IFB
of 3.5". The seal of the car to the kiln is fine. The steel shell of the
car is straight and has suffered no heat impingement and well within
acceptable tolerance.

Don, Marc, Karl, Nils, any other kiln guru.....your input is valued.



Jonathan Kaplan
Ceramic Design Group Ltd./Production Services
PO Box 775112
Steamboat Springs CO 80477

(970) 879-9139*voice and fax