Abstract: A gun for repairing the refractory walls of a coke oven comprising an air-cooled, pressurized, insulated tube which contains an internal pipe for conveying refractory repair material. The tube is mounted in a support at one end, so arranged that the tube can be rotated about its axis and tilted. The other end of the tube has a nozzle for spraying the refractory repair material at right angles to the axis of the tube. The operator is stationed at the support end and can observe the deposition of repair material by looking through a telescope at the support end which is directed to an angled mirror and open sight port at the other end. Air is blown through the tube to keep it cool and out of the sight port at high velocity in order to prevent the refractory repair material from entering the port and coating the mirror.

Abstract: A mobile gunning apparatus is disclosed that is particularly adapted for applying refractory material to the interior of coke ovens, or the like. The apparatus is arranged for mounting on a wheeled vehicle and includes an extendable boom carrying the gunning nozzle and structure enabling the boom and nozzle to be universally movable with respect to the vehicle.

Abstract: In an installation for the electrostatic projection of powders for coating objects, a method of improving the efficiency of projection and deposit of the said powders consists of increasing the relative humidity of the projection gas in the immediate vicinity of the projection nozzle by means of mixing the jet of gas which conveys the coating powder, at the level of the projection nozzle, with a jet of auxiliary gas previously heated and humidified by means of an appropriate liquid. In an alternative method, there is comprised the further step of reducing the temperature of the main jet of gas before this main jet is mixed with the auxiliary gas.The apparatus for carrying the method into effect comprises the heating and humidifying devices for the auxiliary gas and a device for cooling the main gas.

Abstract: A device for shielding a heated surface from infrared detection through an exhaust opening adjacent the heated surface which comprises an exhaust gas conducting member adapted to receive heated exhaust gases from the exhaust opening with the member having a configuration which blocks the exhaust opening from line-of-sight view through the outlet to the member. The exhaust gas conducting member includes apparatus to inhibit heat transfer across its interior surface while promoting heat transfer through the wall of the member. Additionally there is provided a diffusion device for breaking up a main stream of heated exhaust gas into a plurality of smaller streams to reduce infrared radiation from the exhaust gas which includes a body adapted to receive heated exhaust gas with insulation apparatus to maintain the exterior surface of the body at a relatively low temperature. A plurality of openings in the body provide discharge of smaller streams of exhaust gas.