Patent ID: 8002902

Claim:
A method of cleaning the exterior surfaces of water tubes in an HRSG boiler system comprising the steps of: using a first nozzle assembly to clean tubes on a first row of tubes in a heat exchange panel; applying a wedge device a first length into tubes to spread the tubes in the first row of tubes in the heat exchange panel thereby forming a first access lane; inserting a block in the first access lane to maintain the tubes in the spread position and removing the wedge device; applying a wedge device a second length into tubes to spread tubes in a successive row of tubes in the heat exchange panel thereby forming a second access lane aligned with the first access lane; inserting a block in the second access lane to maintain the tubes in the spread position and removing the wedge device; inserting a selected nozzle assembly in the access lanes; and spraying a cleaning fluid via the selected nozzle assembly to clean the exterior surfaces of the tubes wherein the first length is different than the second length.