Remotely operated maintenance and inspection equipment transporter

Claim 1

In a steam generator of a nuclear power installation wherein the generator is essentially a heat exchanger having a shell across the lower portion of which extends a horizontal tube sheet supporting a bundle of vertically extending tubes and surrounded by a wrapper extending downward from the upper portion of the shell to form an annulus with the inside of the shell and terminating a predetermined distance above the tube sheet, a system for cleaning and inspecting that portion of the tubes a predetermined distance above the tube sheet, including, an opening to the annulus through the shell of the heat exchanger, a transporter structure which can be disassembled and passed through the shell opening to a position beneath the lower end of the bundle wrapper and between the tube bundle and the internal wall of the shell where it is reassembled, first wheel structures mounted on the transporter arranged to engage the upper surface of the tube sheet, a cable connected to the ends of the transporter and extending around the periphery of the tube bundle and through the shell opening to a motor means operated externally to move the transporter along the periphery of the tube bundle, inspecting and cleaning structure mounted on the transporter for removing foreign matter from the tube portions above the tube sheet and inspecting the cleaned tubes, and extension structure mounted on the transporter and controlled in lateral movement to engage the inside of the shell wall and the tubes of the bundle for efficient operation of the inspection and cleaning structure mounted on the transporter.