Type Designation; Pump Key For Mtr; Pump Key For Crk And Spk; Technical Data - Grundfos CRK Series Installation And Operating Instructions Manual

4.1.1 MTR/CRK/SPK
MTR/CRK/SPK pumps are used for liquid transfer in machine
tools and in all systems where a tank mounted pump is required.
For liquid transfer, circulation and pressure boosting of cold or hot
clean liquids.
4.1.2 MTRI/CRKI/SPKI
In systems where all parts in contact with the liquid must be made
of high-grade stainless steel, MTRI, CRKI, and SPKI pumps must
be used.

5. Type designation

The standard range of pumps encompasses complete impeller in
chamber combinations. On request, other lengths, against duty
combinations, can be supplied by fitting empty intermediate
chambers instead of standard chambers with impellers.
The pump key on the pump nameplate indicates the number of
chambers and impellers fitted to the pump.

5.1 Pump key for MTR

Example MTR 32- 2 /1 -1 -A -G -A -HUUV
Pump range
Nominal flow rate in m³/h
Number of stages
Number of impellers
Number of impellers with reduced diameter
(MTR 32, 45, 64 only)
Code for pump version
Code for pipework connection
Code for materials
Code for shaft seal

5.2 Pump key for CRK and SPK

Example SPK 8 - 3 / 3 -A -WB -A -AUUV
Pump range
Nominal flow rate in m³/h
Number of stages x 10 (SPK x 1)
Number of impellers
Code for pump version
Code for pipework connection
Code for materials
Code for shaft seal and rubber pump parts

6. Technical data

Pump type
Min liquid temperature °F [°C]
Max liquid temperature °F [°C]
Max operating pressure psi [bar]
Enclosure class

6.1 Ambient temperature

Maximum ambient temperature:
If the ambient temperature exceeds above maximum values or if
the motor is located 3280 ft [1000 m]. above sea level, the motor
output (P2) must be reduced due to the low density and
consequently low cooling effect of the air. In such cases, it may
be necessary to use a motor with a higher output
4
MTR CRK SPK
14 [-10] 14 [-10] 14 [-10]
194 [90] 194 [90] 194 [90]
362 [25] 362 [25] 362 [25]
TEFC TEFC TEFC
104°F [40°C]
P2
[%]
100
90
80
70
60
50
60 80 100
3280
Fig. 1 Relationship between motor output (P2) and
ambient temperature/altitude
Pos.
1
Grundfos MLE and Baldor Motor
2
Grundfos ML Motors
P2
[%]
100
90
80
70
60
50
20 25 30 35 40 45 50 55 60 65 70 75 80
1000
Fig. 2 Relationship between motor output (P2) and
ambient temperature/altitude [metric]
Pos. Motor Power [kW]
1 0.37 - 0.55
2 0.75 - 22
0.37 - 22
3
30 - 75
Example:
From the above figure and key appears that P2 must be reduced
to 88% when a pump with NEMA Premium Efficiency, ML motor is
installed 15584 ft [4750 m]. above sea level. At an ambient
temperature of 167°F [75°C], P2 must be reduced to 74% of rated
output.

6.2 Electrical data

See motor nameplate.

6.3 Frequency of starts and stops

6.3.1 Grundfos ML motors:
250 times per hour for 1/3-3 HP (.37-2.2 kW)
100 times per hour for 5 HP (3-4 kW)
50 times per hour for 7.5-10 HP (5.5-7.5 kW)
40 times per hour for 11-22 kW
6.3.2 Baldor Motors:
20 times per hour on 0.33-5 HP models
15 times per hour on 7.5-15 HP models
10 times per hour on 20-100 HP models
2
1
120 140 160 180
T [°F]
7382 11483 15584 ft
Description
1
2
3
T [°C]
2250 3500 4750 m
Motor make
ML
ML
MLE
Siemens