GB986134A - Improvements in fluid heater cleaners - Google Patents

Abstract

986,134. Soot blowers. BABCOCK & WILCOX Ltd. June 1, 1962 [June 2, 1961], No. 20086/61. Heading F2N. In a fluid heater cleaner having an elongated lance or nozzle tube axially reciprocable to advance the tube from a retracted position and to withdraw the tube to the retracted position, there are means arranged to automatically rock the nozzle tube during reciprocation thereof in a manner tending to compensate sagging of the discharge end of the nozzle tube under the force of gravity acting laterally on the tube. As shown, the nozzle tube 1, extends through a support 6 fixedly mounted on a track member 7 and is supported by a rear support 8 and extends also through an intermediate support 10. The supports 8, 10 consist of wheeled carriages 24, 11 capable of movement along the track 7, and include inner members which allow rotation of the nozzle tube; the latter moves longitudinally relatively to the support 10 on rollers 15. A steam feed tube 31 secured to a support 32 extends coaxially of and within the tube 1 and is supported by rollers 42 on a wheeled carriage 34. A reversible electric motor 45 advances and retracts the nozzle tube and is arranged to drive, through a speedreducing gear 48, a shaft 47 coupled to a chain 53, the two runs of which respectively are attached to the carriage 24 of the support 8 and engageable with a sprocket 61 on a spindle 62 carrying a bevel gear 63 which meshes with a bevel gear 64 secured to the inner member 28 of the support 8 to rotate the nozzle tube. The chain 53 engages a sprocket 54 on a shaft 55 which drives by means of a chain a shaft 67 carrying a bevel gear 68 in mesh with a bevel gear 70 formed as a nut 71 and engaging a screwed shaft 73 coupled by a link 82 to bellcrank levers 84 on a cross-shaft 85 and connected by links 87 to brackets 88 on fixed supports; the frame 7 is also supported by a pivot 89. In operation the motor 45 is started in the appropriate direction and drives the chain 53 to project and rotate the nozzle tube, the steam valve 43 being then opened so that steam is discharged from the nozzle 3. As the chain advances the tube, the shaft 73 is moved longitudinally and through the link 82 effects rotation of the levers 84 to rock the frame 7 downwardly. As the tube 1 advances more and more the length of the unsupported part thereof beyond the support 6 bends more and more and the rear end of the frame is increasingly lowered with respect to the front end of the frame so that the forward end of the nozzle tube is more and more raised in opposition to the sag of the said forward end; the reverse obtains when the nozzle tube is retracted. As shown in Fig. 7, the supports 8 and 10 are moved to the forward end of the track 7 when the nozzle tube is fully advanced. In a modification, the frame 7 is pivoted at the front end thereof, but the rear end of the frame is suspended by a system of wire rope and pulleys forming a speed-reducing hoist. Specifications 636,052 and 769,593 are referred to.