Abstract: An improved cleaning system for a horizontal type tube assembly which can achieve cleaning of the outer surfaces of the tubes in the tube assembly automatically by remote control without necessitating human labor of workers who are compelled to work in a narrow limited space, is disclosed.

Abstract: An automatic tube circumference scanning apparatus automatically performs inspections, repairs and other operation on a group of tubes arrayed in a narrow space and extending in horizontal directions. The apparatus includes an upper support/traverse section mounted on an upper tube in the group of tubes so as to be able to travel along a tube axis and to stop and grip the upper tube, a lower support/traverse section mounted on a lower tube so as to be able to travel, stop and grip the lower tube, a flexible rail extending vertically between the upper and lower support/traverse sections and fixed thereto, and a probe scanning section mounted on the flexible rail so as to be able to move up and down and which grips any arbitrary tube between the aforementioned upper and lower tubes for making a probe scan around such tube.