GB460869A - Improvements in or relating to steam generators - Google Patents

Abstract

460,869. Regulating fuel supply to steam boiler furnaces. SIEMENSSCHUCKERTWERKE AKT.-GES. July 9, 1936, Nos. 19074 and 19075. Convention dates, July 18, 1935 and July 8, 1936. [Class 51 (i)] [Also in Group XIII] The ratio of the feed supply to the fuel supply of a once - through boiler is so regulated by changes of water level in a drum 14, which receives under normal conditions dry saturated steam from the generating sections 7, 11, as to bring the level back to normal. The feed valve 26 is controlled by a float 25 in the drum and by a device 24 operated by pressure varying in accordance with the quantity of steam flowing from the drum. If superheated steam enters the drum from the generating sections, the water level in the drum falls and the flow of steam from the drum increases; both the float and the pressure device then tend to open the feed valve. Conversely, if wet steam enters the drum, the feed valve is closed to a certain extent. The fuel supply is controlled by the pressure in the steam delivery pipe 23. The fuel supply may be controlled by the water level in the drum and the quantity of steam flowing from the drum, and the water supply by the pressure in the steam delivery pipe. In a modification, the steam enters the drum through a pipe coil arranged in the water space and opening into the steam space, and part of the steam may flow directly from the generating sections to the superheating sections under the control of a valve operated in dependence upon the difference of pressure at the inlet and outlet of the drum.