Maintenance
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GA03108_002_C1 - 04/2018 - © Leybold
5.2 Exchanging the Lubricant
Before pumping oxygen (or other highly reactive gases) at concentrations
exceeding the concentration in the atmosphere (> 21 % for oxygen) it will
be necessary to use a special pump. Such a pump will have to be modi-
fied and de-greased, and an inert special lubricant (like PFPE) must be
used.
Observe safety informations 0.3 to 0.5.
The oil-fill port must be sealed air-tight. In the presence of a vacuum, the
entry of air may cause oil-containing gas to enter the pumping chamber via
the impeller seals.
In the case of clean operating conditions, the lubricant is only consumed due
to wear in the bearings and within the gear.
When using PFPE as intended, PFPE is not subject to ageing. It must only be
changed if it is contaminated by the process gas. It can only be determined
for each individual case when the PFPE is so contaminated that it must be
changed. To be sure, we recommend changing the PFPE once a year.
For recycling contaminated PFPE we ask you to consult us. As PFPE we
recommend our LVO 400.
Change the oil more frequently when pumping corrosive vapors or large
amounts of dust or when cycling frequently from atmospheric to working
pressure.
Under such operating conditions it is recommended to regularly check the
neutralisation value (to DIN 51 558) based on a sample of oil. If the neutrali-
sation value of LVO 100 exceeds 2, an oil exchange will be required.
Before removing the oil-drain or oil-fill plug always switch off the pump first
and vent to atmospheric pressure.
When the pump has become warm during operation the casing and the oil
temperature may exceed 80 °C.
Leave the pump to cool down. Always wear protective gloves also to pro-
tect yourself against aggressive residues in the oil.
To simplify the process and also for safety reasons we recommend the use
of our oil-drain facility.
Unscrew the oil-drain plugs (5.1/2) and the oil-fill plug (5.1/3) and drain the
oil.
CAUTION
WARNING
