Steam generator sludge lance apparatus
A sludge lance for a tube and shell steam generator that has a central divider plate that extends substantially the length of a central tube lane substantially bisecting a hand hole through which the tube lane can be accessed. The sludge lance has a nozzle with a spring biased, reciprocally movable plunger that extends against the divider plate and is locked in position by a stream of high pressure cleaning fluid that traverses the nozzle and exits through jets to clean sludge from between the tubes. An alignment tool with a swing arm indexes the jets to assure they are properly aligned with the tube rows and spaced from the divider plate.
1. An alignment tool assembly for a steam generator sludge lance to align the sludge lance with structures within the steam generator, the steam generator having a shell enclosing a tube sheet and a plurality of substantially uniformly diametrically sized tubes extending from the tube sheet with the tubes disposed in a substantially regular pattern having substantially uniform narrow gaps between adjacent tubes, the regular pattern forming a generally central lane with the shell having at least one access opening in-line with the central lane, the alignment tool assembly comprising:
a mounting assembly structured to support a drive assembly and a rail;
an alignment tool structured to move along the rail and determine a linear distance between a sludge lance nozzle assembly on the rail and one the plurality of tubes closest to a pointer on the alignment tool, the alignment tool having a housing face from which the pointer is rotably supported including markings on the housing face that translate the angular position of the pointer into linear distance from the nozzle assembly to one of the plurality of tubes closest to the pointer; and
wherein the pointer swings laterally ninety degrees in a first direction from a vertical orientation to determine the distance between the nozzle assembly and the one of the plurality of tubes.
2. The alignment tool assembly of claim 1 wherein the pointer swings in a second direction, laterally opposite to the first direction to determine the distance between the nozzle assembly and a structure on an opposite side of the nozzle assembly.
3. The alignment tool assembly of claim 2 wherein the structure is a divider plate that extends substantially down the central lane.
4. The sludge lance of claim 1 wherein the pointer swings in the first direction to align the jets with the gaps.