Abstract: An apparatus for removing sludge from the tubes and tubesheet of a steam generator. A support structure is adapted to be mounted at an access port of a steam generator. A lance tube extends from the support structure into the steam generator. A spool attached to a high pressure hose is received in the lance tube. A pinch roller assembly mounted on the support structure is used to move the cylinder through the lance tube. High pressure water flows through slots drilled in the spool and out holes in the lance tube against the tubes and tubesheet. A rocker motor causes back and forth rotation or rocking of the lance tube to create a sweeping action. The lance tube may also be adjusted axially to insure that the water streams are directed to the tube lanes.