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BA-
45.01.0 • US •01/15
6-2
6. Operation
6.2.2
Ventilation valve
The ventilation valve is the regulator for a vacuum
system.
When the pre-set vacuum is reached, it opens and
allows the vacuum pump to draw in additional
atmospheric air.
Check its functionality once a week by a test, with
observation of the vacuum meter on the suction nozzle
of the compressor & vacuum pump.
Blocked vacuum filter.
Blocked exhaust gas silencer.
Suction intake of liquids.
Foaming of the liquid as a consequence of the
condensate from the safety vessels not being
drained soon enough (e.g. due to freezing in winter)
Lack of lubrication oil.
Incorrect lubrication oil
6.2.3
Checking intervals
See chapter
During
operation every
10-20 min
After each
operation
Daily
Weekly
Operating rotation speed
Operating pressure (or) vacuum
name plate
Air discharge temperature
Cooling water temperature
Drain condensate (contains oil!)
silencer/ oil separator
safety tank
Check oil level
Actuate safety valve
Check ventilation valve
Clean machine
Clean inlet/outlet aperture for cooling air
Check fixing of ventilator cowl and covering
plates
The vacuum must not fall below the
permitted vacuum of 200 mbar (cf.
section
Possible operating errors
Operating errors can lead to machine failure.
The following must be avoided:
Too low or too high rotation speed
Too high pressure
Expelling of the entire volume flow via the safety
valve with the pressure pipe closed
Too low vacuum
Too high compressed air temperature (cf.
Poor cooling (cooling air/water supply impaired)
If faults should occur that are caused by
operating errors, Gardner Denver is not
liable for guarantee claims.
Precautions for long standstill periods
Clean the machine thoroughly
If the machine is cleaned with high pressure
water jets, there is a danger of water
intrusion.
After wet cleaning, allow the machine to warm up for
a few minutes to prevent the rotor vanes from
sticking.
If standstill period of rotary compressor/compressor
and vacuum pump lasts more than one month, we
recommend that the machine be switched on once a
month for at least 15 minutes. By this means, all parts
that may be subject to corrosion are supplied with
fresh oil.