Improvements in or relating to apparatus for removing scale from the exterior of boiler tubes

摘要

210,773. Branda, B. Jan. 30, 1923, [Convention date]. Cleaning externally. - A device for cleaning the exterior of boiler tubes comprises a carriage A weighted with lead and provided with wheels C adapted to run on the tops of the tubes. This carriage supports steam cylinders F, controlling valves and a distributing chest L containing oil, which floats on the water condensed in the chest and flows through passages b, c to lubricate the valves and pistons G. The piston G has two piston rods H, I, which support by clamps i, j a hollow tool bar M to which is fixed a lower portion N carrying the tool O. These tools are pivoted on a pin f and consist of thin blades with shaped cutting surfaces to embrace the tubes, stops g, h being provided to limit their oscillation. As the carriage moves along the tools are reciprocated and clean the surfaces of the four tubes with which they contact. The valve control of power fluid through the supply passages 1, 2 to the pistons is of the kind described in Specification 204,682, comprising an automatically actuated piston valve which is operated by the pressure fluid acting through ports 10, 11 leading to the ends of the valve stem, only after the pressure of exhaust above the valve has been reduced sufficiently.