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Leading particulars
DESCRIPTION OF SAFETY PICTOGRAMS
USED IN THIS MANUAL
GENERAL DESCRIPTION
The compressors type XA(S) 137 DD - XA(S) 300
DD7, XA(S) 137 DDG - XA(S) 300 DD7G and
XAHS 107 DD - XAHS 250 DD7 are silenced,
single-stage, oil-injected screw compressors, built for
a nominal effective working pressure, ranging from
7 bar (102 psi) up to 12 bar (175 psi) (see chapter
Technical specifications
).
Engine
The compressors are driven by an oil-cooled diesel
engine.
The engine’s power is transmitted to the compressor
through a heavy-duty coupling.
Compressor
The compressor casing houses two screw-type rotors,
mounted on ball and roller bearings. The male rotor,
driven by the engine, drives the female rotor. The
element delivers pulsation-free air.
Injected oil is used for sealing, cooling and
lubricating purposes.
Compressor oil system
The oil is boosted by air pressure. The system has no
oil pump.
The oil is removed from the air, in the air/oil vessel at
first by centrifugal force, secondly by the oil separator
element.
The vessel is provided with an oil level indicator.
Regulation
The compressor is provided with a continuous
regulating system and a blow-down valve which is
integrated in the unloader assembly. The valve is
closed during operation by air receiver pressure and
opens by air receiver pressure via the compressor
element when the compressor is stopped.
When the air consumption increases, the air receiver
pressure will decrease and vice versa.
This receiver pressure variation is sensed by the
regulating valve which, by means of control air to the
unloader and engine speed regulator, matches the air
output to the air consumption. The air receiver
pressure is maintained between the pre-selected
working pressure and the corresponding unloading
pressure.
This symbol draws your attention to
dangerous situations. The operation
concerned may endanger persons and
cause injuries.
This symbol is followed by
supplementary information.
Содержание XA(S) 137 DD
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