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## natural gas burners

### dianamp@COMCAST.NET on wed 30 may 12

Hi Clayart:

I am helping a friend build a 35 cu ft. catenary soft brick
kiln for cone 6 to 10. We are planning to use 2 burners,
one on each side, aiming in opposite directions, parallel
to the bag walls. I built a couple of natural gas kilns
a long time ago, but not recently. (More recent kiln
building required propane.)

The last natural gas kiln I built was larger than 35 cu. ft.
and I designed it with the potential of a million BTUs
divided among 6 burners. I think, from its performance, that
I never needed that much gas capacity, that it was over engineered.

Do you think that 700 to 750 thousand BTUs is enough for a 35 cubic foot
natural gas kiln, meaning that each burner must be able to provide
half of that amount (about 350K each)?? (The burners we are looking at
can provide that much each.)

What number do you use to
calculate BTUs per cubic foot??

Thanks,

Diana Pancioli
E.M.U.

### Steve Mills on wed 30 may 12

Dear Diana, my last production Kiln was 55 Cu ft gross truck Kiln, 30 Cu ft=
s=3D
etting area.=3D20
It had 2 X 400K naturally aspirated burners horizontally opposed, RH firing=
b=3D
ackwards LH forewards, thus firing anti-clockwise. A little over-gunned bu=
t=3D
it's best that way. Max pressure ever used was 6" water column but had 10"=
a=3D
vaiable. Quietest Gas Kiln I've ever known and totally even, front to back,=
t=3D
op to bottom, reduction cone 9.=3D20
We called it "The Gentle Giant"=3D20

Steve. M

Steve Mills
Bath
UK
www.mudslinger.me.uk
Sent from my iPod

On 30 May 2012, at 12:46, dianamp@COMCAST.NET wrote:

> Hi Clayart:
>=3D20
>=3D20
> I am helping a friend build a 35 cu ft. catenary soft brick
> kiln for cone 6 to 10. We are planning to use 2 burners,
> one on each side, aiming in opposite directions, parallel
> to the bag walls. I built a couple of natural gas kilns
> a long time ago, but not recently. (More recent kiln
> building required propane.)
>=3D20
>=3D20
> The last natural gas kiln I built was larger than 35 cu. ft.
> and I designed it with the potential of a million BTUs
> divided among 6 burners. I think, from its performance, that
> I never needed that much gas capacity, that it was over engineered.
>=3D20
>=3D20
> Do you think that 700 to 750 thousand BTUs is enough for a 35 cubic foot
> natural gas kiln, meaning that each burner must be able to provide
> half of that amount (about 350K each)?? (The burners we are looking at
> can provide that much each.)
>=3D20
>=3D20
> What number do you use to
> calculate BTUs per cubic foot??
>=3D20
>=3D20
> Thanks,
>=3D20
>=3D20
> Diana Pancioli
> E.M.U.

### Eric Ciup on wed 30 may 12

Hi Diana

The reason I answered as I did is that since we have members all over
the world we can't really make assumptions that we are talking about the
same things. There is no ISO committee for Clayart!
My stacking space, ie the exact footprint of my shelves (24"
x24"x36") is 12 cu ft since I have a straight walled kiln with flat
roof. This doesn't count the over hang which can be quite considerable.
Have you considered backing up your 2600 degree brick just with
loose fill vermiculite. It would give slightly better insulation than
k20 brick for less money. I also would only use hard brick in the flame
trenches if at all.
> What cubic measure is your kiln?
> I thought that they were usually discussed in terms of stacking space.
> Certainly not in outside dimensions!!
The kiln will be 2600 degree brick on the hot face, and 2000 degree back
up with
a layer of cement, clay, and vermiculite (or some such) over the top.

The floor will be hard brick backed up with insulating brick.

### Neil Estrick on wed 30 may 12

Go here: http://wardburner.com/technicalinfo/dataguide.html

### Eric Ciup on wed 30 may 12

To give helpful advice we have to know what you mean by 35 cu ft. This
can refer to the outside dimensions, the inside dimensions, or the
stacking space . My own kiln with 7 inch walls could be 12, 19, or 56
cu ft this makes a big difference in your calculations. You also have to
specify your materials, fiber or 2300 insulating brick need less energy
than 26, 28, or hard brick.
My kiln which is built with 2.5 " k23 (4.5" in ceiling and door) backed
by 4.5" of inswool board uses about 220000 btu per hour or 1.5 million
btu per firing.
> I am helping a friend build a 35 cu ft. catenary soft brick
> kiln for cone 6 to 10. We are planning to use 2 burners,
> one on each side, aiming in opposite directions, parallel
> to the bag walls. I built a couple of natural gas kilns
> a long time ago, but not recently. (More recent kiln
> building required propane.)