Improvements in or relating to forced circulation steam boilers heated by waste gases

摘要

661,628. Forced-flow steam boilers; casings. LA MONT INTERNATIONAL ASSOCIATION, Ltd., and BAUER, F. W. June 28, 1949, No. 17068/49. Class 123(ii) A forced-flow steam boiler comprises a casing of substantially square cross-section which is fitted with waste gas upper outlet and lower inlet cones 25, 26 and houses a number of parallel steam generating elements 1. As shown, each element is in the form of straight tube lengths connected in series and, preferably, it extends in the direction of the gas flow from a water distributing header 2 and then back to an outlet header 3, the tube lengths in the return half of the element being offset and staggered with respect to those in the first half. The boiler casing consists of two side plates 13 and a rear plate 14, which are welded together along their adjoining edges and to reinforcing corner angle bars 15, and a removable front ' plate 17 which is secured to reinforcing angle bars on the front vertical edges of said side plates 13. The side plates are connected together by removable tubular ties 27, and the rear and front plates are adapted to support flats 7 to which the bends of the elements 1 are welded. Top and bottom flanges 18, 18 are provided on the sides and rear of the casing, also flanges 19, 20 at the bottom and top of the front plate, for the connection of the cones 25, 26. The casing plates and front plate may be reinforced by welded-on flats 21, 22 respectively, also diagonal cross bracings, (not shown), and they are preferably covered with insulation 31, 33 and external protection plates 32, 34. Access doors, such as 28, 29, are located in the side walls of the casing. The headers 2, 3 may be welded together at 4, attached to the casing by flats 5, and provided with end plates 6 for attachment to the side plates 13.