GB224556A - Improvements in combustion control means for a steam generating plant - Google Patents

Abstract

224,556. Smoot, C. H. Nov. 8, 1923, [Convention date]. Regulating combustion.-In a group of interconnected steam boilers, the supply to each boiler furnace of a fixed proportion of an operative medium, such as fuel and air, is regulated automatically, the condition of such regulation is indicated at a central point and like functions influencing the output of each boiler are indicated in juxtaposition so as to show any departure in the output of one boiler from the average output of all the boilers. As shown in Fig. 1, the steam pressure in the main 9 acts upon a diaphragm 12 of the master controller 1 and operates a spring- loaded yoke 13 connected by a lever 16 to an inverted cup 19 which allows compressed air to escape from the chamber 4 to the atmosphere. the amount of leakage determining the pressure in the chamber 4. An increased load on the boiler reduces the leakage and the pressure in the chamber 4 increases and is transmitted through openings controlled by valves 21 to pressure gauges 25 and through the pipes 26 - - 29 to the various regulators one of which is shown in Fig. 2 as applied to a blower. Increase of pressure of the air on the diaphragm 47 tends to close the valve 55 and reduce leakage of steam to the atmosphere from the chamber 49 by way of the orifice 53. The increased pressure in the chamber 1 is transmitted to the piston 5 which rises and actuates the lever 58 to open the throttle valve of the blower engine. Relative movement between the piston 51 and diaphragm 47 is provided for by a dash-pot 60. The balance of the apparatus is again restored by the increased pressure in the air-supply duct leading from the blower being transmitted to the upper surface of a diaphragm 39, lever 40 and one end of a lever 42, the other end of which is acted upon by the pressure on the diaphragm 47. When the lever 58 is employed to actuate the damper in the furnace air supply conduit, the upper and lower sides of the diaphragm 39 are respectively connected to a venturi tube and Pitot tube in the air supply conduit. In the case of the stack damper, the pressure in the stack is communicated to the diaphragm 39. In a modified form of regulator applied to the engine of the mechanical stoker, the diaphragm 39 is dispensed with and balance is restored to the apparatus by an oil type governor driven by the engine and connected to the lever 42. Indicators 77, 78. Fig. 1, are employed for comparing any group of variables or functions influencing the output. Specification 179,953 is referred to. The Specification as open to inspection under Sect. 91 (3) (a) mentions the application of the invention to furnaces fired by gas or powdered fuel. This subject-matter does not appear in the Specification as accepted.