GB894548A - Sootblower - Google Patents

Abstract

894,548. Soot blowers. THOMPSON (AUSTRALIA) PROPRIETARY Ltd., JOHN. Aug. 29, 1960 [Sept. 8, 1959], No. 29732/60. Class 99(2). A soot-blower com prises a bearing tube 26 extending through a fire box wall 29 and into the fire-box and forming a part of a stator assembly adapted for mounting on the wall, an assembly which is axially movably inside the stator assembly, and a nozzle tube 31 housed inside the tube 26 and forming part of the movable assembly and which is provided with a cleaning fluid outlet. There are actuating devices incorporated in the assemblies which in response to the application of fluid pressure thereto axially advance the nozzle tube so that the outlet end thereof projects into the fire-box beyond the adjacent end of the tube 26, and means for retracting the nozzle tube from the axially advanced position in response to cleaning fluid pressure. As shown the nozzle tube 31 has a keyway 33 slidable longitudinally of a key 34 fixed in a bearing sleeve 35 mounted in antifriction bearings 36 in a easing 27, and includes an impeller head 37 formed with helical vanes 38 and rotatable within the skirt 39 of a non- rotatable piston 40 having fluid ducts 50 communicating with holes 49 in the head 37 and ducts 52, 53 leading to the clearance space 54 between the nozzle tube and bearing tube 26. Cleaning fluid is admitted via a main valve 56 to the chamber 28 to project the nozzle tube against the action of a buffer spring 45, and via a valve 61 to the ducts 51 to cause the tube to rotate. On completion of a soot-blowing operation, the valves 56, 61 are closed and the twoway valve 57 operated to admit cleaning fluid to the ducts 52 via the pipe 60 to thereby retract the nozzle tube. The nozzle tube oultets 16 may be formed tangentially of the tube so that the tube is rotated by the reaction of the cleaning fluid jets. The nozzle tube may be non-rotatable in which case the fluid spaces defined by the element 38 are straight instead of helical. The tube 26 passes through at least one of the water tubes 30 of the boiler and is thereby kept relatively cool; alternatively, the tube is coated with refractory material and projects between adjacent water tubes. The plug 15 of the nozzle tube may be omitted and the outlet end of the tube be fashioned to form a restricted nozzle outlet.