Oerlikon RUVAC WA, Installation And Operating Instructions Manual

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Operation
49 GA03107_002_A4 - 09/2015 - © Oerlikon Leybold Vacuum
With small vacuum vessels, the maximum permissible pressure differential
can be briefly exceeded (max. 3 min) upon start-up. If a pressure switch has
been installed, do not set it to this higher pressure because it will fail to pro-
tect the pump against overload in the event of a greater gas quantity.
It is advisable to switch the RUVAC WA on and off via a pressure switch to
ensure that it runs only in the permissible pressure range.
Switching on Again at ATEX Operation
If the pump was shut down, then a cooldown phase of 30 minutes needs to
be maintained before switching on again. This prevents the ignition tempera-
ture from being exceeded because of the internal temperature increase.
Since due to the better cooling of the pump housing it cools down faster
than the impellers inside, and inadequate cooling down time can cause a
mechanical contact between impellers and pump housing.
4.2 Operation
Do not operate the pump without having connected the flanges to a vacu-
um system.
The screws of the flanges on the suction and the pressure side must not
be loosened in the presence of a vacuum even if the pump is not running.
During operation of the RUVAC, check the oil level and the condition of the
oil in the oil level glass and the oiler from time to time. Correct as required
(see Sections 5.2 and 5.3). Normally, the oil LVO 100 is light brown. If it turns
dark, this is a sign of early ageing due to excessively high temperatures.
For ATEX operation check the oil levels daily. Moreover, check the coupling
daily as to any running noises.
Dirt Ingress into the Oil via the Piston Rings
In the case of dusty processes which are frequently vented with atmospheric
air, there is the risk of dust being forced into the oil chambers. This can be
prevented by a pressure equalisation between the oil chamber and the pump
chamber. For this, install a valve at the oil inlet which during operation is
opened simultaneously with the venting valve.
Run the Roots pump exclusively under the operating conditions for which it
has been designed. Any modification of the operating parameters (e. g.
intake pressure, intake temperature, ratio between Roots pump and back-
ing pump) for a longer period may place an inadmissible thermal load on
the pump. Increases in temperature which are not compensated by taking
suitable measures may damage the Roots pump and/or the backing
pump.
Hot surfaces, risk of suffering burns.
Notice safety information 0.3.
Note the labels on the pump.
NOTICE
CAUTION
CAUTION