Michael Porter Interview
What was the state-of-the-art in burners when you wrote your first book?
In my view, state of the art for forge, furnace, and kiln burners saw funnel openings
replaced by large enclosed air chambers with rounded slot air intakes instead of holes;
Where does the Diablo burner fit in the evolution of gas burners?
Since slot shapes obviously improved burner performance over holes, I took the idea a step further
by using rectangular openings with bevel edged ends, in order to reduce air drag to the absolute minimum.
The new design also increased flow speed of the gas/air mixture down the mixing tube.
Increased flow speed allowed use of parallel stepped nozzles.
Chile Forge has improved my burner design through the use of industrial construction techniques,
like precision cut air openings, creating a standardized version; the finest burner I've yet seen.
Having tested the Diablo, how does it compare to other burners on the market?
The Diablo burner can be tuned to a near perfect single wave front neutral flame throughout nearly all of its
turn-down range, which is the range that a flame can be reduced from its highest stable setting, to the lowest
stable setting a given burner can put out. So far as I know, no other burner can or does make such a claim.
Are BTU charts an accurate way of comparing burner performance? No; British Thermal Units are the
measure of total heat produced by a given fuel, or of the system that a fuel is run through. BTU ratings have
nothing to do with burner efficiency or highest flame temperature. Going by these ratings, the hands down
winner among gas burners would be cheap imported weed burners. To use an extreme example, forest fires
put out a plenty of heat, but they aren't useful for doing practical work. Powering heating equipment with a
weed burner isn't very practical either.
Please explain what the burner flame shows about burner performance.
The flame's look and sound indicate what kind of combustion is happening at any given moment;
for instance, any hint of green in a flame indicates incomplete combustion, not only of the primary flame,
but predictably in any secondary flame also. A dark blue flame indicates that it is an oxidizing flame,
which is to say that there is too much oxygen available in the fuel/air mixture. Both oxidizing (oxygen rich)
and reducing (fuel rich) flames will run at lower temperatures than neutral flames. Reducing flames will
also produce carbon monoxide, while oxidizing flames cause excessive oxidation of heating parts in forges,
and many problems, including accelerated breakdown of crucibles, in furnaces. A light to medium blue color
indicates a neutral flame, which is normally what is desired; there are exceptions to this rule; at times an
operator may wish to use a slightly reducing flame to assure desired results in forge welding, and in some
pottery work. I don't know of any advantage to an oxidizing flame.