Atlas Copco XRVS 1350 Instruction Manual Download

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AIR FLOW (ALL UNITS)

Air drawn through the airfilter (AFce) into the
compressor element (CElp CEhp) is compressed. At
the element outlet, compressed air and oil pass into
the air receiver/oil separator (AR/OS).

The check valve (CV) prevents blow-back of
compressed air when the compressor is stopped. In
the air receiver/oil separator (AR/OS), most of the oil
is removed from the air/oil mixture.

The oil collects in the receiver and on the bottom of
the separator element.

The air leaves the receiver via a minimum pressure
valve (MPV) which prevents the receiver pressure
from dropping below the minimum working pressure,
even when the air outlet valves are open (specified in
section

Limitations

). This ensures adequate oil

injection and prevents oil consumption. The
minimum pressure valve (MPV) also functions as a
check valve.

The system comprises temperature sensors (TS),
pressure sensors (PS) and a working pressure sensor
(WPS).

OIL SYSTEM (ALL UNITS)

The lower part of the air receiver (AR) serves as an oil
tank.

Air pressure forces the oil from the air receiver/oil
separator (AR/OS) through the oil cooler (OC), the oil
filters (OF) and the oil stop valve (OSV) to the
compressor element (CElp CEhp).

When the compressor is stopped and / or there is no
pressure in the system, the oil stop valve (OSV)
prevents the oil from flowing back into the
compressor element.

The thermostatic by-pass valve (TBV) starts opening
when the oil temperature is 80°C (176°F) (when no
Oiltronix is installed). With installed Oiltronix, the
thermostatic by-pass valve starts opening when the oil
temperature is 40°C (104°F).

The compressor element has an oil gallery in the
bottom of its casing. The oil for rotor lubrication,
cooling and sealing is injected through holes in the
gallery.

Lubrication of the bearings is ensured by oil injected
into the bearing housings.

The injected oil, mixed with the compressed air,
leaves the compressor element and re-enters the air
receiver, where it is separated from the air as
described in section

Air flow (all units)

. The oil that

collects on the bottom of the oil separator element is
returned to the system through a scavenging line (SL),
which is provided with a flow restrictor.

The oil filter by-pass valve (BVof) opens when the
pressure drop over the filter is above normal because
of a clogged filter. The oil then by-passes the filter
without being filtered. For this reason, the oil filter
must be replaced at regular intervals (see section

Preventive maintenance schedule

Oiltronix (XRYS + XRXS)

The oil system of XRYS and XRXS units is equipped
with the Oiltronix

ΤΜ

system, a system that

electronically controls oil temperature:

•

At all time the oil temperature is kept to a
minimum to elongate the lifetime of oil and
compressor elements and to ensure proper
lubrication.

•

The oil temperature is also controlled at all time to
a minimum level above the dewpoint, preventing
water vapour to condense in the vessel or oil
system.

The optimum temperature is calculated based on
ambient conditions and operating conditions. In a
next step the 3-way valve is positioned in order to
achieve this optimal oil temperature by more or less
bypassing the oil cooler. In this way oil temperature
regulation is more efficient.