Leading Particulars; Description Of Safety Pictograms Used In This Manual; General Description - Atlas Copco XAHS 146 Dd S3B APP Instruction Manual

Leading particulars

DESCRIPTION OF SAFETY PICTOGRAMS
USED IN THIS MANUAL
This symbol draws your attention to
dangerous situations. The operation
concerned may endanger persons and
cause injuries.
This symbol is
supplementary information.

GENERAL DESCRIPTION

followed by
The compressors type XAHS 146 Dd, XATS 156 Dd,
XAS 186 Dd, XAVS 166 Dd and XAHS 186 Dd are
silenced,
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 a liquid-cooled diesel
engine.
The engine's power is transmitted to the compressor
through a heavy-duty coupling.
All machines meet Tier 4I / Stage IIIB emission
standards.
single-stage, oil-injected screw
- 14 -
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 an electronic 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.