5. Applications
Grundfos multistage, horizontal, end-suction centrifugal pumps,
types CR-H and CRN-H, are designed for a wide range of
applications.
CR-H and CRN-H
CR-H and CRN-H pumps are suitable for liquid transfer,
circulation and pressure boosting of cold or hot clean liquids.
CRN-H
Use CRN-H pumps in systems where all parts in contact with the
liquid are made of high-grade stainless steel.
5.1 Pumped liquids
The CR-H and CRN-H are capable of pumping thin, clean, non-
flammable liquids, not containing solid particles or fibers. The
liquid must not attack the pump materials chemically.
When pumping liquids with a density and/or viscosity higher than
that of water, use motors with correspondingly higher outputs,
if required.
6. Operating conditions
6.1 Ambient temperature and altitude
If the ambient temperature exceeds the maximum temperature
limits of the pump or the pump is installed at an altitude
exceeding the altitude values in the chart below, the motor must
not be fully loaded due to the risk of overheating.
Overheating may result from excessive ambient temperatures or
the low density and consequently low cooling effect of the air at
high altitudes. In such cases, it may be necessary to use a motor
with a higher rated output (P
).
2
P2
[%]
100
90
80
70
60
50
60
80
100
120
3280
7382
Fig. 1
Relationship between motor output (P
ambient temperature/altitude
Legend
Pos.
Description
1
NEMA Standard efficiency motors
2
NEMA Premium efficiency motors
Example: From fig. 1 it appears that P
when a pump with a NEMA Premium efficiency, ML motor is
installed 15584 feet above sea level. At an ambient temperature
of 167 °F, P
of a standard efficiency motor must be reduced to
2
74 % of rated output.
6.2 Liquid temperature
The tables on pages 19 and 20 state the relationship between
liquid temperature range and maximum permissible operating
pressure.
The maximum permissible operating pressure
Note
and liquid temperature ranges apply to the pump
only.
2
1
140
160
180
T [°F]
11483 15584
ft
) and
2
must be reduced to 88 %
2
6.3 Maximum permissible operating pressure and
liquid temperature for the shaft seal
The diagrams below apply to clean water and
Note
water containing anti-freeze liquid.
CR 1s to CR 20 H
p
p
[bar]
[psi]
400
25
300
20
HQQE
15
HQQV
200
10
100
5
0
0
-40
0
40
80
-40
-20
0
20
Fig. 2
Operating range of standard shaft seals for CR 1s to
CR 20 H
CR 32 to CR 90 H
p
p
[bar]
[psi]
500
HQQE / HQQV
30
400
25
300
20
KUHE / KUHV
15
KUBE / KUBV
200
KUUE / KUUV
10
100
5
0
0
-40
0
40
80
-40
-20
0
20
Fig. 3
Operating range of standard shaft seals for CR 32 to
CR 90 H
Shaft
Description
seal
O-ring (cartridge) (balanced seal),
HQQE
SiC/SiC, EPDM
O-ring (cartridge) (balanced seal),
HQQV
SiC/SiC, FKM
O-ring (cartridge) (balanced seal),
HUBE
TC/carbon, EPDM
O-ring (cartridge) (balanced seal),
HUBV
TC/carbon, FKM
Bellows, metal (cartridge),
KUBE
TC/carbon, EPDM
Bellows, metal (cartridge),
KUBV
TC/carbon, FKM
Bellows, metal (cartridge),
KUHE
TC/carbon with embedded TC,
EPDM
Bellows, metal (cartridge),
KUHV
TC/carbon with embedded TC,
FKM
Bellows, metal (cartridge),
KUUE
TC/TC, EPDM
Bellows, metal (cartridge),
KUUV
TC/TC, FKM
TC = tungsten carbide.
HQQE
120
160
200
240 t [°F]
40
60
80
100
t [°C]
HQQE
KUBE
120
160
200
240 t [°F]
40
60
80
100
t [°C]
Max.
temperature
range
[°F]
–22 °F to +248 °F
–4 °F to +194 °F
+32 °F to +248 °F
+32 °F to +194 °F
+32 °F to +248 °F
+32 °F to +194 °F
+32 °F to +194 °F
+32 °F to +194 °F
–22 °F to +194 °F
–4 °F to +194 °F
7