Ulvac VD151, Инструкция по эксплуатации

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YK08-0028-DI-002-08
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5.3 Required Motive Energy
Motive energy to drive the Vacuum pump is a total value of the work of the mechanical element
on the rotary friction (mechanical work) and the work of compressing the air (compression work)
that becomes maximum when the suction pressure is between 3×10
4
~ 4×10
4
Pa.
If the pressure went down under 10Pa, the compression work becomes smaller, then most of the
motive energy shall be spent on the mechanical work.
General use of the Pump shall indicate the largest load pressure range while the suction pressure
was between 3×10
4
~ 4×10
4
Pa. Operation opening the Gas ballast valve would require larger
motive energy at all the time as its compression work is large even the suction pressure was
small. Further, when the temperature of the Pump site was low (in cold district or outdoor
installation) starting the Pump would require larger motive energy since the Pump oil temperature
was low and its viscosity is higher. However the motive energy value shall decrease and come
stable as the oil viscosity comes lower while the Pump temperature shall rise as it goes through
operation. “Motor” listed on the “Table 1 Performance specifications” are adopted taking into
consideration of the above condition to drive the Pump.