Entrainment inlet ports

Sixties, mercury as the medium was almost completely replaced by oil. To obtain as high a vapor stream velocity as possible, he allowed the vapor stream to emanate from a nozzle with supersonic speed. The pump fluid vapor, which constitutes the vapor jet, is condensed at the cooled wall of the pump housing, whereas the fransported gas is further compressed, usually in one or more succeeding stages, before it is removed by the backing pump. The compression ratios, which can be obtained with fluid entrainment pumps, are very high if there is a pressure of 10 mbar at the inlet port of the fluid-entrainment pump and a backing pressure of 10 2 mbar, the pumped gas is compressed by a factor of 10 ... 

Flexible impeller pump (Figure Hf) uses elastomeric material such as rubber as rotor. Its impellers or vanes continuously deflect or straighten as they pass a cam between the inlet and outlet ports. Liquid is carried and compressed by the flexible impellers from pump Inlet to outlet. Its advantages are it is an inexpensive pump. It can handle liquid with solids, abrasives, or entrained gases. It is dry seif-priming, its disadvantages are its low flow and pressure limits, about 150 gpm and 6D psi. It cannot run dry and its operating temperature is limited to about 300 F,... 

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