GB429365A - Improvements in or relating to tube cleaning apparatus for boilers and the like - Google Patents

Abstract

429,365. Boiler cleaners. HANDOLL, P. G., 340, Brownhill Road, Catford, and DIAMOND BLOWER CO., Ltd., 91, Bishopsgate, both in London. Dec. 20, 1933, No. 35823. [Class 99 (ii)] A cleaner for marine fire-tube boilers of the kind in which a steam jet is directed onto the tubes to be cleaned from a rotatable nozzle 17, which is located within a tubular housing 16 mounted in the wall 11, 12, 13 of the boiler furnace and is slidable axially between the two extreme positions shown by full and dotted lines in Fig. 1, is provided with a snapover device to ensure rapid movement of the nozzle from its operative to its inoperative position. The nozzle is formed with an enlargement 19 adapted to coact with a seating 18 on the inside of the housing 16, and is mounted on the end of a spindle 29 which is provided at its outer end with a chain pulley 31 and intermediate its ends with a piston 34, of smaller diameter than the nozzle, and also a valve 35 having a plain cylindrical portion 36, of smaller diameter than the piston, and a conical seating 37. The piston 34 is located within a cylindrical extension 33 of the cover plate 30 of the wall casting 14 carrying the housing 16, and the valve seating 13 is adapted to coact with a ring 40 located on arms 38 projecting from the casting extension 33, cleaning steam being admitted from a supply passage 41 to the space between the casting 14 and the extension 33 and arms 38. The cleaner is completed by a lever 45 having a forked arm 46 engaging a groove 47 in the hub 48 of the pulley 31, and a spring 49 adapted normally to retain the nozzle in its inoperative or retracted position. In operation, and with the nozzle retracted, the lever 45 is drawn forward to shift the spindle 29 axially, thus advancing the nozzle into its operative position with the enlargement 19 engaging the seating 18 and opening the valve 35, the movement of the nozzle being assisted when the valve is opened by the differential steam pressure on the said nozzle. The nozzle is then rotated, and finally retracted by pushing back the lever 45. The retraction of the nozzle is at first resisted by the steam pressure, but immediately the cylindrical portion 36 of the valve enters the seating 40 the differential steam pressure on the piston 34 will effect rapid movement of the nozzle to its initial position. Condensate in the casting 14 is removed by a drain passage 50 which is connected to a blow-off pipe 51 and is provided with an ejector jet 52 communicating with the steam supply. The nozzle is preferably provided with a nozzle cap 21 having several orifices, e.g. three, inclined in various directions as described in Specification 429,366. Fig. 5 shows a modification for a locomotive boiler in which the casting 14 is mounted directly upon the front plate 73 of the firebox by studs 74 and the nozzle has a shorter stroke and is both moved axially and rotated by a single handle 71.