GB226080A - Improvements in mechanical grates - Google Patents

Abstract

226,080. Babcock & Wilcox, Ltd., (Deutsche Babcock-&-Wilcox Dampfkessel- Werke Akt.-Ges.). March 26, 1924. Grates; fuel, feeding; crowns and roofs.-In mechanical grates of the kind described in Specification 202,896, wherein the front part of the grate is completely enclosed and is connected to a suction arrangement, a front ignition grate 4, Fig. 1, is provided between the feed hopper 2 and the automatic stoker 1 in order to dry and ignite the fuel received thereon. The grate 4 is preferably adapted to rid itself automatically of ash. The space 5 between the grate 4 and a damper 3 is connected by a pipe 6 to the chimney, or to a suction fan which draws the gases through the fuel on the grate and discharges them under the mechanical stoker. The lower part 7 of the grate 4 is also arranged as a grate, with means such as hooks 8 to retard the fuel and maintain an igniting fire at this point. The part 7 is open to the atmosphere on its underside, permitting air to enter and pass through the incoming fuel into the space 5. A duct 9 connects the space above the grate 4 with the furnace chamber, and by means of ducts 11 provided with a damper 12 the admission of air can be controlled to regulate the temperature above the grate 4. In a modification, Fig. 2, the duct 9 terminates in the front part of the combustion chamber and is provided with a mouth 13 into which extends one end of a pipe 11<1>, which is open to the atmosphere at its other end and produces an injector-like action. Part of the mixture of air and hot gases issuing from the mouth 13 passes through an adjustable damper 10' to the grate 4, the remainder being delivered to the rear portion of the furnace.