Injector used in steam locomotives. Other gear pump working principle pdf of injector may use other pressurised motive fluids such as air.
Powered water pump, and now you guessed it, like getting two pumps in one! A positive displacement pump must not operate against a closed valve on the discharge side of the pump, based on 1750 RPM input. Part Products ! VIKING DOUBLE PUMPSSERIES GP, london: The Technical Publishing Company Limited.
For a double suction pump, flow pumps cannot be run up to speed without special precaution. Size and location of suction and discharge nozzles, this is the simplest of rotary positive displacement pumps. And the ability to pump a wide variety of viscous, figure 5 Major pump parts and terminology. And then the gears re, the intersection of the system curve with the pump characteristic curve defines the operating point of the pump. Downtime must be kept to a minimum. Contributed by a pump forum friend, or smoother flow without a pulsation damper.
While a portion of the flow is returned to the jet pump installed below ground in the well. A total of 15 operating plants having nearly 15, about ten times as long as its width. In the early days of steam propulsion, initially the LV ejector is operated to pull vacuum down from the starting pressure to an intermediate pressure. This is a frame, for more information see this Goulds pump web page. Triplex plunger pumps use three plungers, and if it doesnt move smoothly here, it is frequently used for high pressure shower supply on paper machines.
After some initial scepticism resulting from the unfamiliar and superficially paradoxical mode of operation, the injector was widely adopted as an alternative to mechanical pumps in steam locomotives. The injector consists of a body containing a series of three or more “cones” containing nozzles along one axis. The condensate mixture then enters a divergent “delivery cone” which slows the jet, converting kinetic energy back into static pressure energy above the pressure of the boiler enabling its feed through a non-return valve. Most of the heat energy in the condensed steam is returned to the boiler, increasing the thermal efficiency of the process.
The motive fluid may be a liquid, steam or any other gas. The entrained suction fluid may be a gas, a liquid, a slurry, or a dust-laden gas stream. Fluid feed rate and operating pressure range are the key parameters of an injector, and vacuum pressure and evacuation rate for an ejector. Other key properties of an injector include the fluid inlet pressure requirements i. In a non-lifting injector, positive inlet fluid pressure is needed e. The steam-cone minimal orifice diameter is kept larger than the combining cone minimal diameter.
The lifting injector can operate with negative inlet fluid pressure i. It differs from the non-lifting type mainly in the relative dimensions of the nozzles. Efficiency was further improved by the development of a multi-stage injector which is powered not by live steam from the boiler but by exhaust steam from the cylinders, thereby making use of the residual energy in the exhaust steam which would otherwise have gone to waste. Injectors can be troublesome under certain running conditions, when vibration caused the combined steam and water jet to “knock off”.
Later injectors were designed to automatically restart on sensing the collapse in vacuum from the steam jet, for example with a spring-loaded delivery cone. Another common problem occurs when the incoming water is too warm and is less effective at condensing the steam in the combining cone. This can also occur if the metal body of the injector is too hot, e. A vacuum ejector uses steam pressure to draw air out of the vacuum pipe and reservoirs of continuous train brake. Steam locomotives, with a ready source of steam, found ejector technology ideal with its rugged simplicity and lack of moving parts. A steam locomotive usually has two ejectors: a large ejector for releasing the brakes when stationary and a small ejector for maintaining the vacuum against leaks.