GB785156A - Automatic blowdown control mechanism for steam separator - Google Patents

Abstract

785,156. Steam boiler blow-down apparatus. VAPOR HEATING CORPORATION. Nov. 7, 1955 [Nov. 22, 1954], No. 31786/55. Class 123(2) An automatic blow-down device for a steam and water separator 13 of a coiledtube steam generator used to supply steam to the heating systems of a Diesel-powered passenger train comprises a blow-down valve 14 consisting of a body 33 having a lateral sludge outlet passage 37 and a bottom gland 43 through which passes the stem 42 of the valve element 41, the valve being urged by a spring 44 to its closed position. Secured to the valve body 33 is an air cylinder assembly 60 comprising a casing 62 housing a piston 64 the plunger 65 of which projects through the lower end of the casing and abuts a rocker arm 67 the other end of which underlies the valve stem 42. Admission of air under pressure from a conduit 72 above the piston drives it downwardly against a spring to open the blow-down valve. The air supply is controlled by a solenoid-actuated valve 74 the winding of which is periodically energized by a timer mechanism mounted on a control panel disposed in the locomotive cab. The timer mechanism comprises a motor M which drives a timer cam 99 effecting the closure of a switch 91 for one second during each twenty second interval of time. The timer cam 99 is connected by a gear train to a second cam 103 which closes a switch 92 for twenty seconds during each five minute interval. The switches 91, 92 are in series in the solenoid circuit so that when both are closed together the blow-down operation is effected automatically. A switch S is provided to isolate the automatic actuating device, e.g. when the locomotive is at a station, and, to allow the separator to be blown down manually e.g. before entrv into a station, a pushbutton switch 93 is provided to shortcircuit the switches 91. 92. The valve 41 may also be operated manually by means of a foot-pedal (Fig. 6, not shown).