"Rafael Molina-Rodriguez (Rafael Molina-Rodriguez)" on thu 9 jan 97
This past summer one of my students asked me to design and with his
help construct a gas kiln. We built a 24 cu. ft. hard firebrick sprung-arch
down-draft. The burner system is four "Alfred" type 2" pipe burners
using propane fuel with electric blowers.
I suggested he use cast flame retention nozzles and threaded the pipe
for this. Due to financial concerns, he purchased clay burner tips ( $ 9
ea. each compared $ 45 ea. for cast nozzles) from Alpine as a short
Anyone in the group have an opinion of whether one is better than the
Bruce Michaels on fri 10 jan 97
> for this. Due to financial concerns, he purchased clay burner tips ( $ 9
> ea. each compared $ 45 ea. for cast nozzles) from Alpine as a short
I wonder what would happen if one of the clay burner tips broke or
cracked during a firing? It seems to me that the kiln would start
drawing in more outside air and less flame and maybe not get to the
temperature wanted or would take a long time to get there. The flame
might even move back to the outside of the kiln. If I was building the
kiln I think I might be concerned about this. It could be a fire
hazzard. It's a judgement call.
Vince Pitelka on fri 10 jan 97
>I suggested he use cast flame retention nozzles and threaded the pipe
>for this. Due to financial concerns, he purchased clay burner tips ( $ 9
>ea. each compared $ 45 ea. for cast nozzles) from Alpine as a short
>Anyone in the group have an opinion of whether one is better than the
Bad choice. After all the expense of building a kiln, this is a crazy place
to try to save a few bucks. Those Alpine ceramic burner tips are a terrible
design. Your student would have been far better off making his own flame
retention tips out of cast-iron pipe couplings. There are a very wide
variety of designs for flame-retention tips out there, and the fundamental
priciple behind them all is that they create turbulence at the burner tip,
which mixes the air and gas thoroughly and keeps the flame right on the tip
and reduces the chances of flash-back into the burner tube. With the
cast-irong pipe couplings, you can simply drill three or four sets of
opposing 1/4" holes though the center of the pipe coupling, press lengths of
1/4" rod through these holes, and tack-weld them on the outside with Ni-rod.
Obviously, the holes must not all be on the same plane, or the rods will run
into each other. This matrix of rods will create the necessary turbulence.
The total cost of these tips, not counting your labor, will be less than
five dollars apiece.
Vince Pitelka - vpitelka@Dekalb.Net
Phone - home 615/597-5376, work 615/597-6801
Appalachian Center for Crafts, Smithville TN 37166
Erin Hayes on sat 11 jan 97
We have an old Alpine in the college studio which has the ceramic burner
tips. I replaced them when I was hired because they were really
deteriorated. The new ones fit okay, but there is some space around the
fitting that tends to divert the edges of the flame every once in a while.
Doesn't seem to hurt the firing or the burners, but it makes the burners roar
a little more than usual.
If I had my choice (and the money to see it through), I would invest in some
of those swanky burners Marc Ward has. Certainly I would ask him about your
situation - I imagine he has a solution for you.