Abstract: A method for welding together two workpieces includes the steps of abutting workpieces together along respective edges of each of the workpieces, and locating one end of a rotatable tool astride the edges and against the workpieces. The tool is provided with a relatively narrow pin extending from the working end of the tool to engage the workpiece edges. The tool and pin are rotated to heat the workpiece edges, and the tool and workpieces are relatively moved. Electric current is supplied between the workpiece edges and the pin, with electrical resistance occurring between the workpiece edges and pin to provide heat in addition to the heat generated by friction occurring between the pin and workpieces to weld the workpieces together.

Abstract: A device for vaporizing liquid fuel supplied to a furnace chamber. The device comprises a tubular structure having one end adapted to extend into the chamber, and, a plate located over said end, the tube and plate being made of heat resistant materials. Openings are provided in the wall of the tube at locations adjacent and in communication with the plate, the tube being adapted to receive liquid fuel for direction to the plate; the plate, in turn, is adapted to vaporize drops of liquid fuel striking the plate.

Abstract: A ring furnace including pits bounded laterally by side wall flues, the side wall flues being connected in series by means for conducting gases between the side wall flues of the pits, so that heat in previously fired side wall flues can preheat air for combustion in a fired side wall flue and exhaust gases from the fired side wall flue can give up heat to articles in pits bounded by yet-to-be-fired side wall flues, wherein the improvement includes a Y-baffle inverted and centered in at least one of the side wall flues.

Abstract: The method of burning fume, including combustible gases and gas-borne particles, comprising moving the fume in a tube having a blind end and one or more slits in the tube short of the end, while the fume is at least partially at ignition temperature, and emitting the fume into the air, the slit width and the slit total area being chosen such that the fume velocity through the slits will be more than the flame velocity and up to the flame blow-out velocity. The device includes a tube having a closed end and slits having a width between one-eighth and 1 inch and preferably about five-eighths inch, and a length of between one-eighth and one-half of the circumference.