Patent GB-190300137-A (GB)
Title: Improvements in or relating to Apparatus for Automatically Regulating the Supply of Feed Water to Steam Boilers, applicable also for Giving an Alarm in Case of Excess or Deficiency in the Height of the Water Level in Steam Boilers.
Inventor: BROOKE ROBERT GRUNDY
Filed: 1903-01-02
Granted: 1903-11-05
Abstract: 137. Brooke, R. G. Jan. 2. Feedwater, supplying and controlling; alarms, high and low water.-The supply of water to a steam boiler is controlled by an equilibrium or cone valve 4. This valve may control the flow of water direct to the boiler, an outlet to a bye-pass pipe, or the supply of steam to the pump or injector, and is operated by, an expanding and contracting tube a secured to a 'tubular casting b having a flanged end secured to the boiler d or a column secured to the boiler. This column may have a gauge glass and a cooling-coil. The pipe a is surrounded by a casting m, through which the feedwater may be passed to cool water entering the tube a. This casting rests on the tubular casting b, and has a stuffing-box q. The upper end of the tube a is closed by a cap r having a valve s closed by a spring t and opened by a lever u to liberate air. Lateral pins v engage an annular lever or collar w pivoted on a rod 6, which rests on the casting m, and connected by a rod 5 to a spring- raised lever y fulcrumed on a bracket x and carrying an adjustable screw z. The valve-rod 1, made in two parts connected together as shown, is held against the screw z by a spring 3 and guided by a bracket 7. Fig. 1 shows the valve 4 arranged so as to control the passage of the water to a bye-pass. When a single pump is used with two or more boilers, each bye-pass valve is controlled independently, and the bye-pass has a weighted valve which opens only under a pressure exceeding the boiler pressure. In a modification, the valve is arranged horizontally and is connected through a bell-crank lever and a rod to the lever y. Fig. 9 shows a modification in which the expansion tube a is fixed to the cover 16 of a box b having a pocket 17 cooled by feedwater passed through its jacket 18. An extension 19 has a lateral cavity 20 and a bevelled end. Steam is supplied to the tube a through a pipe 22. The valve is operated by a spring 8 and the tube a through rods and levers, as shown. When the valve is used to control the supply of steam to a pump, a bye-pass passage 9<a> is formed in the diaphragm 9<b>. The tubular part b may cover two holes in the shell of the boiler, the upper hole having a light check valve to prevent the admission of steam to the expansion tube until the water level descends to the lower hole. To increase the cooling effect on the water in the expansion tube, the lower end of this tube may be connected to a coiled pipe in the water-circulating chamber, or to a chamber with a water jacket. When the valve controls the supply of steam to an injector, it is operated suddenly by a tumbler, the short arm of which acts on two nuts on the valve rod. The tumbler is actuated by a forked arm acted on by two loose collars pressed by springs against shoulders at the central part of a spindle operated by the expansion tube through rods and levers. The automatic equilibrium valve 4, shown in Fig. 20, controls the passage of water from the inlet chamber 47 to an intermediate chamber 48 separated from another chamber 49 by a check valve 45, the passage from this chamber to the outlet chamber 50 being controlled by a handoperated valve 46. A hollow or solid rod may be placed centrally within the tube a and used to operate the valve. A nut 2<c>, Fig. 1, may be carried by the rod 1 to act in conjunction with spring contacts 56, 57 to complete the electric circuits through low and high water alarm bells 58, 59. The modification used with an injector may also be applied to supply steam to a steam whistle used as a low-water alarm.