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BA-
45.01.0 • US •01/15
4-5
4. Installation
Safety and monitoring features
The operating safety of the machine, i.e. operation
without danger, requires the following safety and
monitoring devices:
Suction side
Vacuum filter
Ventilation valve
Vacuum meter
Pressure side
Safety valve
Non-return valve
Thermometer
Manometer
Contact protection
Protection against rotating parts and burns
Machine protection
Speed monitor
Maintenance indicator on the combination air filter
Oil level safety feature
If these notes are not adhered to, the
guarantee loses its validity.
4.4.1
Vacuum meter (4.1/18)
For adherence to the permitted operating vacuum.
Fitted in the suction pipe directly in front of the suction
nozzle
4.4.2
Vacuum filter (4.1/2))
The vacuum-sealed filter protects the machine from
mechanical contamination. Fitted in the suction pipe.
When fitting, pay attention to the direction of flow and
the space required to replace the filter element.
Vacuum filter type SFA is not suitable for
excess pressure.
Vacuum filters of the series SFD are
pressure shock-proof up to 11 bar.
4.4.3
Ventilation valve (4.1/1)
The ventilation valve is the regulator for the appliance
and the safety feature in the suction pipe. It is
absolutely essential.
If the intake suction vacuum falls below the pre-set
minimum value, the ventilation valve opens and the
machine draws in atmospheric air. This serves to limit
the suction pressure to the permitted minimum
pressure, e.g. 200 mbar.
If the ventilation valve is mounted or
fitted incorrectly or interfered with, an
increase
of
the
vacuum and the
temperature
could
CAUSE
AN
EXPLOSION!
1.
Vacuum filter SFA or SFD
2.
Servo-pipe 10x1.5
3.
Ventilation valve BV-DN
4.
Flange fitting
5.
Compressor and vacuum pump
6.
non-return valve
7.
To/from four-way tap
Figure 4-3:
Installation of the servo-controlled
ventilation valve
The servo-controlled vacuum regulation and limitation
valve from Gardner Denver achieves the highest
standard of functional reliability and operating
precision. The setting is not dependent on the flow
rate. The compact construction facilitates simple,
space-saving installation.
4.4.4
Non-return valve (4.1/4)
The non-return valve prevents retro-flow when the
machine is switched off. It is not completely gas-tight.
In machines of the RFW series, the non-return valve is
mounted to the pressure nozzle.
Observe the direction of flow (arrow on the housing).