The Steam Injector
A theoretical and practical treatise on the design and operation of injectors and on the flow of fluids through and the design of nozzles.

78 THE STEAM INJECTOR. page, due to the presence in the i'eed pipe of water at practically boiling point, is obviated. The cock h is for putting the valve e out of action. Means are provided for lifting the main non-return valve a in the feed supply pipe b from its seat, so that the water in the feed tank or hot well can be warmed with steam from the injector steam nozzle in the usual manner. Sucli means comprise a screw-threaded valve spindle i having a collar j upon its operative end which works within a bridge-like exten- t)TE AM Fig. 58. sion k upon the valve a. When the valve spindle is in a micl-way position, as shown, the valve a can open and close indepe-ndently thereof, but if the valve spindle is screwed outwards it lifts the valve from its seat. To provide for the regulation of the water supply of an injector simultaneously with the steam supply, injøctors known as “ one movenient ” injectors are employed. A form of “ one movement” injector is illustrated at figs. 57 and 58. The spindle a of the steam valve is coupled to the spindle b of the water valve, so that when the steam valve