Best placement of burner for an aluminum forge

[birch97]

I am building an aluminum melting furnace. I have the burner done but I don't seem to be able to find where the best placement of the burner should be. I plan to have a refractory poured floor with a drain hole in the bottom. The hole will be covered with a refractory disc which will hold the crucible. How high above the disc should the burner be placed? Should it be placed at the bottom of the crucible? Thanks for any help.

[12bolts]

Place your burner flush with the bottom of the furnace, orientated so that it is horizontal, but tangenital, so the flame swirls around the crucible but not against it. Base of the crucible wants to be, at the minimum, at least above the centreline of the burner tube, but better if it is above the top edge of the burner tube.

Cheers Phil

[trapper23]

For my$0.02 worth id agree with 12 bolts although it seems to depend a tad on how big the diameter of the burner tube is.... i found that you need it close to the bottom and tangential the lower the better, the height of the burn chamber also has an effect. Avoid the tangential if the tube is only used as a blower in the sense that you run coal or charcoal maybe coke as a fuel.
I run kerosene and waste oil mix at about 8psi air pressure but have problems with flow rate of the oil. work in progress for me propane as a fuel is too expensive