GB827835A - Improvements relating to fluid heater cleaners - Google Patents

Abstract

827,835. Soot blowers. BABCOCK & WILCOX Ltd. April 4, 1956 [April 4, 1955], No. 9814/55. Class 99(2). In a soot blower the supply of clearing fluid to the blower nozzle, carried by a rotatable shaft 103, is controlled by a piston valve 110 which forms a pressure reducing valve and is held on its seat 117 by high pressure steam supplied to the space 107 and transmitted past the loosely fitting piston to the upper side 107A thereof, opening of the valve being controlled by a relay valve 160 which extends through the piston valve 110 and is actuated through a lever 142 and push rod 141 by a cam 140 on the nozzle shaft 103, which relay valve releases the pressure in space 107 whereby the high pressure in space 107 forces the valve 110 off its seat 117 against an adjustable stop 113. The valve 110 has a tapered projection 130B cooperating with an orifice 118 to form the pressure reducing means for the steam supply, the lift of the valve 110 being adjusted to vary the pressure reduction by adjustment of the stop 113. Grooves 124 in the upper end of piston 110 permit the fluid pressure to reach the inside of the piston when it is a butting the stop 113. The relay valve has an extended stem 139 provided with a square portion 150A engaging in a square bore in the stop 113 so that rotation of the stem 139 by engagement of a tool with the upper square end 150B of the stem causes adjustment of the stop 113. The stem 139 is locked in its adjusted position by engagement of the square end 150B in a channel in its operating lever 142. Specifications 533,609 and 636,052 are referred to.