YO99-0874-DI-002-18
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2.5 Pump Performance
2.5.1 Ultimate pressure
The ultimate pressure of the mechanical booster pump varies with the ultimate pressure of the fore
pump. If the ultimate pressure becomes high, it is necessary to check the ultimate pressure of the fore
pump too.
If the pump was used to pump a large quantity of moisture or was left with the intake and exhaust ports
opened to atmosphere for a long period, the ultimate pressure may not lower to the prescribed value
immediately after pump startup due to moisture absorption in the pump. In most cases, no-load run
of the pump for about 24 hours will evaporate the adsorbed substance and restore the pump to normal.
2.5.2 Pumping speed
The pumping speed varies with the pressure difference between the intake and exhaust ports and
rotating speed. Even if the intake pressure is the same, the difference pressure between the intake
and exhaust ports can be reduced by increasing the pumping speed of the fore pump, so that the
pumping speed increases in a pressure range higher than the pressure at which the maximum pumping
speed can be attained. Conversely, the pumping speed of the mechanical booster pump also lowers if
the pumping speed of the fore pump is low.
Summary of Contents for PRC-003A
Page 10: ...YO99 0874 DI 002 18 ix Fig 1 Warning Label PRC 003A PRC 006A PRC 012A PRC 018A...
Page 24: ...YO99 0874 DI 002 18 8 2 4 Dimensional drawing Fig 3 PRC 003A Dimensional drawing...
Page 25: ...YO99 0874 DI 002 18 9 Fig 4 PRC 006A Dimensional drawing...
Page 26: ...YO99 0874 DI 002 18 10 Fig 5 PRC 012A Dimensional drawing...
Page 27: ...YO99 0874 DI 002 18 11 Fig 6 PRC 018A Dimensional drawing...
Page 57: ...YO99 0874 DI 002 18 41 Fig 15 PRC 006A Optional attachment figure...
Page 58: ...YO99 0874 DI 002 18 42 Fig 16 PRC 012A Optional attachment figure...
Page 59: ...YO99 0874 DI 002 18 43 Fig 17 PRC 018A Optional attachment figure...
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