Improvements in or relating to high water level safety control devices for the steamdrums of steam generators

摘要

685,400. Feedwater regulators. WILSON, S., and STEPHEN and SONS, Ltd., A. Feb. 12, 1951 [Nov. 8, 1950], No. 27266/50. Class 123 (ii), [Also in Group XXIX] A steam boiler high water level safety control device comprises a vessel 4 having an inlet 5, in communication through a stand pipe 11 with the interior of the steam-and-water drum 10 of the boiler, and also an outlet port 7, controlled by a valve 17 operatively connected by levers 18, 24 to a float 16 located within said vessel 4. The pipe 11 depends to the maximum level line 14 and is terminated in a perforated box or cage 12, the arrangement being such that, at normal water level, the vessel 4 is filled with steam and the float 16 is at its lowermost position with the valve 17 closed, but, when the level reaches the line 14, water will flow into the chamber 4 to lift the float 16 and open the valve 17; pressure water will then flow through the outlet 7 to actuate a control valve to shut off the feedwater supply to the drum 10 and operate a whistle or other signal. The boiler drum may also be provided with a control adapted to permit steam to flow therefrom to close a boiler fuel supply valve, for example of the kind described in Specification 378,689, [Group XXIX], when the water falls below a predetermined low level.