Patent ID: 6764030
Filing Date: 2004-07-20
Classification: F28G,Y10S

Abstract:
A lance tube nozzle block for a sootblower for cleaning internal heat exchanger surfaces by impingement of a jet of a cleaning medium, the nozzle block comprising:a nozzle block body defining a longitudinal axis, a hollow interior, a distal end, and a proximate end with the proximate end receiving the cleaning medium; a downstream nozzle positioned adjacent the distal end of the nozzle block body for discharging the cleaning medium, the downstream nozzle having a first inlet end, a first converging section near the first inlet end, a first diverging section joining the first converging section and terminating with a first outlet end, a first throat at the point where the first converging section and the first diverging section are joined, a first expansion zone between the first throat and the first outlet end, the downstream nozzle having a first axis of discharge substantially perpendicular to the nozzle block body longitudinal axis, the nozzle block body hollow interior and the downstream nozzle cooperating such that the cleaning medium flowing in the direction of the longitudinal axis from the proximate end to the distal end through the nozzle block body hollow interior does not flow substantially beyond the downstream nozzle first inlet end; and an upstream nozzle for discharging the cleaning medium positioned at a longitudinal position of the lance tube nozzle block displaced from the distal end and the downstream nozzle, the upstream nozzle having a second inlet end, a second outlet end, wherein the cleaning medium enters the upstream nozzle through the second inlet end and exits through the second outlet end with a second axis of discharge substantially perpendicular to the nozzle block body longitudinal axis, a second converging section near the second inlet end, a second diverging section joining the second converging section defining a second throat, and a second expansion zone between the second throat and the second outlet end.