EN – 8
Oil - Noise limiter - Antisuckback
Oil has several important functions in the pump:
– It lubricates mechanical components (bearings, seals, rotor, vanes, etc.).
– It makes moving parts relatively tight by limiting internal leakage.
– It carries away the heat produced by the compressed gases.
Oil
Choosing the right oil
Not all oils produce the same ultimate pressure in a given pump. Ultimate pressure
depends on the saturated vapor pressure of the oil, its viscosity and its ability to dissolve
gases.
Good pumping conditions are related to the type of oil used. The choice depends on:
– Expected pump performance.
– Chemical aggression and corrosion of pumped gases.
– Accessories used.
– Desired maintenance intervals and total operating cost.
The manufacturer has selected various types of oil for its pumps (
see page 17
).
9
7
6
8
Lubrication
The pump is equipped with a
lubrication
system which regulates the oil flow rate
required in the vacuum pump. In addition this system also ensures the gassing of
the lubrication oil and therefore
the low noise level
of the pump.
When the pump begins
to operate, the cooled
oil (from the bottom of
the oil casing) is pulled
in by the oil pump (
2
)
and drawn in through
the oil inlet tube (
3
). It is
then agitated by a venturi
tube (
4
) and forced
into the chamber (
6
)
which is adjusted by the
diaphragm spring system (
7
).
The discharge pressure of the oil pump (
2
) lifts the diaphragm off its seat (
8
) allowing
oil to reach the functional block via the oil injection line (through seats) (
8
). An orifice
(
9
) equipped with a jet located in the oil lubrification systems allows trapped gases to
be expelled out of the chamber (
6
).
C1 series
C1 series pumps are equipped with an automobile type oil filter, which traps particles
from the oil pumps exhaust. Due to its construction, its life time is reduced when
pumping on corrosive products in large quantities. In this case, an auxiliary oil filtering
system is recommended and the filter is replaced by a stainless steel short-circuit
stopper (
see accessories page 14
).
