- 4 -
4
3
3.2
Construction (fi g. 3 and 4)
VWZ pumps are constructed in fi ve main sections, i.e. gear box (
Y
3
), compression stages (
S
1
,
S
2
), oil supply (
L
1
to
L
8
), cooling
system (
R
,
Y
40
,
R
1
) and separator systems (
Z
,
J
1
,
J
2
,
J
3
) on the suction side and exhaust side (optional). The pumps are water
cooled. The built in pressure relief valve (
Q
) permits start-up and operation of the pumps over the entire vacuum range.
A
Vacuum
connection
B
Exhaust
connection
G
1
Drive
H
4
Cooling liquid fi lling cap
and pressure relief valve
I
4
Cooling liquid check
J
1
Filter candles in oil mist separator
J
2
Manometer for oil mist separator
J
3
Drain cock for oil mist separator
L
Oil
pump
L
1
Oil pump feed line
L
2
Oil pump leakage line
L
3
Lubrication (LP) stage drive end
L
4
Lubrication (LP) stage non-drive end
L
5
Lubrication (HP) stage drive end
L
6
Lubrication (HP) stage non-drive end
L
7
Bearing lubrication (LP) stage
L
8
Bearing lubrication (HP) stage
Q
Pressure relief valve
R
Heat
exchanger
R
1
Fan
S
1
Low pressure stage (LP)
S
2
High pressure stage (HP)
U
High temperature and
operating
temperature
thermostat
U
2
Cooling liquid de-aeration
V
7
Level control condensate / oil
Y
Fresh oil tank
Y
1
Bearing oil tank (LP) stage
Y
2
Bearing oil tank (HP) stage
Y
3
Gear box unit
Y
30
Gear box oil
Y
40
Cooling liquid
Z
Oil mist separator
