LEYBOLD 960702FP, Original Operating Instructions

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300419816_002_C1 - 11/2016 - © Leybold
4.4 Shutdown
Under normal
circumstances, all that you need to do is to switch off the pump.
The intake port of the SOGEVAC
®
contains an anti-suck back valve, which closes
the intake port when the pump is shut down, thus maintaining the vacuum in the
connected system and preventing oil from being sucked back into the system. The
valve’s functioning is not impaired by gas ballasting, but its cleanliness must be
taken care of.
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 Section 4.2).
If the pump is to be shut down for an extended period or if the pump has to be
stored, proceed as follows: When pumping harmful substances, take adequate
safety precautions.
Drain the oil (see Section 5.4).Pour in clean oil up to the bottom edge of the oil-
level glass (see Section 5.4) and let the pump run for a few minutes. Then drain
the oil and pour in clean oil up to the top edge of the oil-level glass (see Section
5.4). Seal the connection ports. Special preservation or slushing oils are not neces-
sary.
When the pump has been switched off due to over-heating, initiated by the motor
or its protection, the pump must be cooled down to the ambient temperature, and
must only be switched on again manually after having eliminated the cause. In or-
der to prevent the pump from running up unexpectedly after a main power failure,
the pump must be integrated into the control system in such a way that the pump
can only be started by a manually operated switch. This applies equally to emer-
gency cut-off switches.
In case of switching processes in connection with a pump which has warmed up
under operating conditions, the pump must then not be directly switched on again.
4.5 Pump Ultimate Pressure
If the system cannot reach the pressures specified in the technical date, measure
the ultimate pressure directly at the pump’s intake port after disconnecting the
pump from the system.
The ultimate pressure of non-condensable gases (partial pressure of air) can only
be measured with a compression vacuum gauge or a partial pressure gauge. Pre-
cise measurements can only be obtained with calibrated instruments.
Upon initial start-up, after prolonged idle periods or after an oil change, it takes a
while until the pump reaches the specified ultimate pressure. The pump has to at-
tain its operating temperature, and the pump oil has to be degassed. We recom-
mend operating the pump initially with the
gas ballast valve open.
The ultimate pressure depends on the pump temperature and the pump oil used.
The best ultimate pressure can be obtained at a low pump temperature and by us-
ing the recommended oil types.
Operation
CAUTION