GB587747A - Improvements in and relating to boiler feedwater systems - Google Patents

Abstract

587,747. Feedwater supply systems for steam boilers. COX ENGINEERING CO., Ltd. (Schaub Engineering Co., F. H.). Jan. 15, 1945, No. 1169. [Class 123 (ii)] In an installation comprising a steam boiler 10, associated feedwater supply tank 23 and motordriven feed pump 16, the boiler supplying one or more steamconsuming loads 12, each of the latter is provided with a condensate return line 13, 21 which leads to the tank 23 and is fitted with the usual steam trap 14 and also with a pressure control valve 28 to maintain the pressure on the said load 12. The pressure control valve 28, Fig. 2, comprises a chamber 28a locating a flexible diaphragm 31 and integral valve member 29, the latter projecting from the chamber 28a into the condensate line 21 and the diaphragm 31 being urged in a valve-closing direction by a spring 32 bearing upon the upper side thereof in opposition to. the pressure in the line 21 at the inlet side of the valve acting through a passage 33 ; the valve thus opens and closes upon an increase or decrease respectively in the required pressure in the line 21. The line 21 terminates in a submerged perforated pipe 22 in the lower part of the feedwater supply tank 23. Makeup water is supplied to the tank 23 through a float-valve controlled pipe 25, and the tank is fitted with an atmospheric vent pipe 26 and a water outlet pipe 30 leading to the inlet of the pump 16, the outlet of the latter being coupled to the boiler by pipes 20, 15 and through an intermediate heat exchanger 18 which houses a tube bundle 19 in the condensate return line 13, 21.