Ulvac VS1501, Инструкция по эксплуатации

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SK00-4390-DI-002-11
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4.4 Gas Ballast Function
This product is installed with the Gas ballast function as standard. Connect the Needle valve,
pipe and the like with the Gas ballast port (G3/8) subject to the purpose to use the function. It is
applicable to breathe in the condensed gas such as the steam and solution vapor. Breathed
condensed gas shall be liquefied through the Compress process of the Pump, mixed with the
Pump oil and then cycled mixed together inside the Pump unit. This status brings you the same
situation that you used the high steam pressure oil that raises the ultimate pressure. It also
shortens the life cycle of the Shaft seal since the oil lubrication shall deteriorate.
If introduced the air or dry nitrogen through the Gas ballast port just before the Pump
compression process, the condensed gas is not liquefied but exhausted with the air through the
Exhaust valve.
To use the Gas ballast, breathe in the air through the Gas ballast port before sucking in the
condensed gas and operate the Pump around twenty minutes; this is because the “Gas ballast
effect” becomes larger as the Pump temperature is higher. Wait until the Pump temperature
rises around 70°C to open the Vacuum valve (Fig. 2, 3) So as to operate the Pump. The “Gas
ballast effect” under low temperature shall be lower than the specified process performance.
Note further that keeping the Gas ballast valve open when not breathing in the condensed gas
shall cause the Pump oil splashing and power loss and further rise the ultimate pressure. You
have to note also that the condensed gas might remain in the Pump oil after you have exhausted
a lot of condensed gas or exhausted the condensed gas (air or gas that contains less water or
other steam that contaminates the oil) without opening the Gas ballast valve since the process
capacity of the condensed gas by the Gas ballast valve is limited.
In such a case, close the Vacuum valve, breathe in the air through the Gas ballast port and idle
operate the Pump. Then the oil temperature shall rise up and be cleaned by means of the Gas
ballast effect. Keep on idle operating the Pump without opening the Gas ballast valve as far as
the specified ultimate pressure is attained. You need to replace the Pump oil if it was not cleaned
after operated long time.
CAUTION
The Vacuum pump gets high temperature (70°C ~ 80°C) during operation.
As the Gas ballast port also gets high temperature, be sure to wear
protective gear such as a pair of gloves.
Ensure to close the Gas ballast port to start operating the Pump.
The oil might jet out of the Gas ballast port during the operation around
high pressure range.
CAUTION
If you kept opening the Gas ballast port when not exhausting the
condensed gas, it might cause the oil splash, power loss or ultimate
pressure rise.
Keep the Gas ballast port closed when not exhausting the condensed gas.