GB189909039A - Improvements in Centrifugal Pumps. - Google Patents

Abstract

9039. Thirion, H. A. April 29. Centrifugal pumps; starting.-Consists of means for re-priming the pump when accumulated air prevents it from drawing. The pump is fitted with non-return suction and delivery valves, and with two other valves, one for the discharge of accumulated air and the other for putting the suction pipe above the suction valve in communication either with the delivery above the delivery valve or with a supply tank. These two latter valves may be hand. operated plug valves on one spindle, or lift valves connected together and to either the delivery or the suction valve so as to be operated automatically. In another modification, Fig. 4, the delivery valve A, on closing owing to the pump becoming unprimed, lifts the valve F and piston J, thus closing the outlet K and admitting pressure water to the piston H to open the valves B', D'. The valve B<1> allows the discharge of accumulated air, and the valve D' admits water from the delivery into the pump. The same arrangement of valves is also shown controlled by the suction valve. All the arrangements of valves described above may be controlled electrically, as, for instance, by means of a solenoid in circuit with the motor. To prevent whirling of the water at the top of the suction pipe, which would delay repriming, blades P, Figs. 4 and 5, are provided.