Abstract: A deposit removal high pressure spray apparatus for removing heat conduction inhibiting deposits on U-tubes at the top of a shell and tube type of nuclear steam generator (10) tube bundle (16) by crawling along flanged outboard support beams (18) above the U-tubes bundle. The apparatus includes: a crawler (66) with motive means 68 for "inch worm" movement; a rotationally driven base 62 provides movement of the sprayhead to either side of the outboard support beam; a rotationally driven extension arm 60 on rotating base 62 has an elongated reciprocally driven elevator 58 thereon; and, a wrist 52 reversibly and rotatably driven by motor 54a sweeps sprayhead 52 with nozzles 56 to clean the top of the bundle 16 tube lanes of 90.degree., 45.degree. and 135.degree. efficiently.

Abstract: A deposit removal high pressure spray apparatus for removing heat conduction inhibiting deposits on U-tubes at the top of a shell and tube type of nuclear steam generator (10) tube bundle (16) by crawling along flanged outboard support beams (18) above the U-tubes bundle. The apparatus includes: a crawler (66) with motive means 68 for "inch worm" movement; a rotationally driven base 62 provides movement of the sprayhead to either side of the outboard support beam; a rotationally driven extension arm 60 on rotating base 62 has an elongated reciprocally driven elevator 58 thereon; and, a wrist 52 reversibly and rotatably driven by motor 54a sweeps sprayhead 52 with nozzles 56 to clean the top of the bundle 16 tube lanes of 90.degree., 45.degree. and 135.degree. efficiently.