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CVHH-SVX001G-EN
compression (refer to the following figure). Notice that
some of the liquid refrigerant flashes to a gas because
of the pressure drop created by the orifice plate, thus
further cooling the liquid refrigerant. This flash gas is
then drawn directly from the economizer into the
second-stage impellers of the compressor. All
remaining liquid refrigerant flows out of the
economizer, passing through another orifice plate and
into the evaporator.
Figure 48.
Pressure enthalpy curve
Condenser
Economizer
Evaporator
Compressor
Second Stage
Compressor
First Stage
6
5
4
3
1
2
Pressur
e
Enthalpy
P
3
P
1
P
2
Figure 49.
Refrigerant flow, 2-stage
Oil and Refrigerant Pump
Compressor Lubrication System
A schematic diagram of the compressor lubrication
system is illustrated in the following figure. Oil is
pumped from the oil tank (by a pump and motor
located within the tank) through an oil pressure
regulating valve designed to maintain a net oil
pressure of 20 to 24 psid (137.9 to 165.5 kPaD). It is then
filtered and sent to the braze plate heat exchanger oil
cooler located above the oil tank and on to the
compressor motor bearings. From the bearings, the oil
drains back to the oil tank.
Summary of Contents for CVHH CenTraVac
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