Atlas Copco XA(S) 186 Dd, Instruction Manual

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11
Instruction Manual
2. LEADING PARTICULARS
2.1 D
ESCRIPTION OF SAFETY PICTOGRAMS USED IN
THIS MANUAL
Fig. 2.1 General view of XAVS 166 Dd with some options
2.2 G
ENERAL DESCRIPTION
The compressors type XAHS 146 Dd, XATS 156 Dd, XA(S) 186
Dd, XAVS 166 Dd and XAHS 186 Dd are silenced, single-stage,
oil-injected screw compressors, built for a nominal effective
working pressure, ranging from 7 bar up to 14 bar (see chapter
8. ,
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.
– 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.
– Cooling system
The engine is equipped with a liquid cooler and intercooler. All
compressors are equipped with an oil cooler.
The cooling air is generated by a fan, driven by the engine.
– Safety devices
A thermal shut-down switch protects the compressor against
overheating. The air receiver is provided with a safety valve.
The engine is equipped with low oil pressure and high coolant
temperature shut-down switches and a coolant level switch.
– Frame and axle
The compressor/engine unit is supported by rubber buffers in the
frame.
The standard unit has a non-adjustable towbar with a towing eye.
As an option the unit can be equipped with an adjustable towbar, an
overrun and parking brake and towing eyes type DIN, ball, ITA, GB,
NATO, AC (France), (for available options see chapter
7. ).
The braking system consists of an integrated parking brake and
overrunbrake. When driving backwards the overrunbrake is not
engaged automatically.
– Bodywork
The bodywork has openings at the shaped front and rear end for the
intake and outlet of cooling air and hinged doors for maintenance and
service operations. The bodywork is internally lined with sound-
absorbing material.
– Lifting eye
A lifting eye is accessible when the small door at the top of the unit
is unlocked.
– Control panel
The control panel grouping the air pressure gauge, control switch etc.,
is placed at the right hand/ rear end corner.
– Data plate
The compressor is furnished with a data plate showing the product
code, the unit number and the working pressure (see chapter
9. ).
– Serial number
The serial number is located on the right-hand side towards the front
on the upper edge of the frame and also on the data plate.
This symbol draws your attention to dangerous
situations. The operation concerned may endanger
persons and cause injuries.
This symbol is followed by supplementary information.