In each of the three receivers shown there is a ball float which appears through the side of the receiver, Fig. [590]; these depend upon the principle of specific gravity for their operation. The lever fastened to the ball float operates the throttle valve of the pump; as the vessel fills with water the float rises opens the throttle valve, and starts the pump.
In Fig. [589] is shown the Deane automatic duplex steam pump and receiver fitted with valves for hot water; it is also provided with three separate inlets for convenience in connecting the returns.
In placing the apparatus, it is only necessary to so locate it that all returns will drain naturally towards receiver and that there are no pockets in the piping.
When it is desired to use the automatic receiver as the sole means of feeding the boilers, it will be necessary to introduce a small supply of water from some outside source to equalize the loss which occurs. It is desirable that this water should flow into receiver rather than into discharge pipe.
Fig. 590.
Fig. 591.
Fig. [590] shows a Mason steam pump with receiver attached. This pump is described elsewhere at length. Fig. [591] represents the Worthington duplex steam pump with its specially designed receiver.