Installation
4990671000 February 2008
18
4.6.7
Guard
The drive of the machine and the hot pressure lines
must be protected by guards.
It must not be possible to touch rotating or reciprocat-
ing machine parts accidentally.
4.6.8
Bellows
To limit the connection forces in the suction and pres-
sure line of the liquid ring pump, vacuum-tight and
pressure-tight bellows must be installed.
At the same time, the bellows isolate solid-borne noise
of the suction and pressure lines.
4.6.9
Speed monitor
Speed control of the liquid ring pump and a speed in-
dicator in the operating area of the machine are recom-
mended. For permitted speed range, see chapter 4.8
“Drive”.
4.7
Operating fluid
For start-up, the liquid ring pump requires an amount
of water sufficient to form the liquid ring.
Therefore, when installing the pump, make certain that
the water tank is located so that when the operating
water feed valve is open and the tank contains a mini-
mum of water, the liquid ring pump fills with water up to
the middle (also see Operating Instructions). If this is
not ensured there may be problems in starting the
pump (no conveyed medium flow).
If the water tank is located so that the liquid level is
above the middle of the liquid ring pump, an automatic
water stop valve must be installed in the operating wa-
ter supply line. This valve must open when the pump
starts and close when it is stopped to prevent inunda-
tion of the pump.
If the liquid ring pump is installed above the water level
in the tank, a pump is required to ensure the operating
water supply. The design of that pump must be such
that the liquid ring pump is supplied with sufficient op-
erating fluid. We will be glad to assist you in selecting
the right pump.
Because liquid is removed from the working space and
also because heat must be dissipated, the liquid ring
pump requires a constant supply of operating fluid. For
this, the covers of the machine have a G 1
1
/
4
" connec-
tion (only one operating water supply connection is
needed, i.e. either on the A side or B side).
If the piping has sufficiently low resistance (feeding line
diameter R1
1
/
2
" to R2", depending on pipeline length
and layout) no recirculation pump may be needed for
the operating water supply provided the arrangement
of the liquid ring pump is such that the middle of the
pump is at a lower level than the minimum liquid level
in the storage tank.
A level control of the operating liquid must be-
provided if the machine is operating in a poten-
tially explosive atmosphere.
4.7.1
Operating water back-cooling and
storage tank
A circulation cooling system is required for back-cool-
ing the operating water. The circulation cooling must
be able to handle the following amounts of heat.
To reduce the loss of liquid by the exhaust air to a min-
imum and to ensure sufficient operating hours of the
system, a combined operating water storage and sep-
arating tank is needed. For minimum sizes, refer to the
table below.
The above minimum water storage figures relate to
systems with water back-cooling.
Systems without water back-cooling require substan-
tially larger storage tanks to ensure sufficient operating
hours of the liquid ring pump without running the risk
that the recommended limit temperature of 55 °C the
operating water inflow is exceeded.
Suction dramatically reduces at higher temperatures.
Aqualine
1100
1600
2100
2700
Amount of heat
to be
dissipated
at 1.5 bar
(g)
at 0.5 bar
(g)
at 400 mbar
at 200 mbar
kW
50
25
29
33
65
32
39
48
78
39
48
57
50
58
67
Recom-
mended pipe
diameter oper-
ating water line
R1
1
/
2
"
R1
1
/
2
"
R1
1
/
2
"
R1
1
/
2
"
Recom-
mended mini-
mum tank size
ltr
250
350
450
600
Recom-
mended water
volume in the
tank
ltr
150
225
300
400
