Oerlikon 10926, Руководство по эксплуатации

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24 GAET02307_002_10 - 06/2008 - © Œrlikon Leybold Vacuum
Operation
With the gas ballast valve open and at operating temperature, the Sogevac®
pump can pump pure water vapor up to the water vapor tolerance indicated
in the Technical Data. The pump’s water vapor tolerance can be increased by
raising the operating temperature.
Use a screwdriver to open the gas ballast valve. The running noise of the
pump is slightly louder when the gas ballast valve is open. Before opening
the pump to vapo
u rs, ensure that the gas ballast valve is open and that the
pump has been warmed up for about 30 minutes with closed intake line.
Do not open the pump to condensable vapo u rs until it has warmed to
operating temperature ; pumping process gas with a cold pump results in
vapo
u rs condensing in the oil.
For porcesses with a high proportion of condensable vapo u rs, slowly open
the intake line after reaching the operating temperature to prevent excessive
quantities of vapor entering the pump.
One sign of condensation of vapo u rs in the pump is a rise in the oil level
during operation of the pump.
During pumping, vapo u rs may dissolve in the oil. This changes the oil
properties and causes a risk of corrosion in the pump. Therefore, do not
switch off the pump immediately after completion of the process. Instead,
allow the pump to continue operating with the gas ballast valve open and
the intake line closed until the oil is free of condensed vapo
u rs. We strongly
recommend operating the pump in this mode for about 30 minutes after
completion of the process.
In cyclic process operation, the pump should not be switched off during the
intervals between the individual working phases, but should continue to run
with gas ballast valve open and intake port closed (if possible via a valve).
Power consumption is minimal when the pump is operating at ultimate
pressure.
Once all vapo u rs have been pumped off from a process (e.g. during drying),
the gas ballast valve can be closed to improve the ultimate pressure.
4.2 Switching off / Shutdown
Under normal circumstances, all that you need to do is to switch off the
pump.
The intake port of the Sogevac
®
pumps contains an anti-suckback valve
which closes the intake port when the pump is switched off, thus maintaining
the vaccum in the connected apparatus and preventing oil from being
sucked back into the apparatus. The valve’s functioning is not impaired by
gas ballast operation.
Nevertheless, the anti suck-back valve is not a safety valve and operates
correctly only if clean and undamaged. A valve must be installed if oil back
streaming is to be avoided be all means.
When pumping condensable media, let the pump continue to operate with
the gas ballast valve open and the intake line closed before switching off
(see § 4.1).
Caution
Note