GB377100A - Improvements in or relating to water tube steam generators - Google Patents

Abstract

377,100. Feedwater regulators for steam boilers. SULZER FR’RES SOC. ANON., Winterthur, Switzerland. Jan. 15, 1932, No. 1301. Convention date, Feb. 7, 1931. [Classes 123 (ii) and 123 (iii).] High pressure boilers in which the working medium is evaporated in a system of tubes in parallel have the main feed supply at the inlet end and additional supplies at intermediate points in the several tubes regulated in accordance with the steam temperature. A set of preliminary tubes 1a, 1b, 1c fed by a pump 2 discharge through a common pipe 3 into a second set 4a .. 4d delivering superheated steam to a pipe 5. Additional supplies introduced through pipes 7a .. 7d are controlled by temperature-responsive devices 6a .. 6d through the agency of valve-operating servomotors 9, these devices also being connected to a servomotor 12 controlling a valve 13 in the main feed pipe. In operation on a rise in temperature above a predetermined value increased feed is supplied at the intermediate points and if when the limits of regulation have been reached the steam temperature is still excessive the servomotor 12 is actuated to adjust valve 13 thus increasing the feed to the preliminary set of tubes. In a modification a temperature-controlled device in pipe 3 regulates the main feed pump, separate pumps. controlling the inflow of additional medium into each of the second set of tubes. Additional supplies of medium may comprise saturated steam.