Grundfos MS 4000, Руководство по эксплуатации продукта

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10
MS Motors
Operating Conditions
Operating Conditions
Cooling
The cooling of the motor depends on the temperature
and the flow velocity of the pumped liquid past the
motor.
To ensure sufficient cooling, the values for maximum
temperature of the pumped liquid and its flow velocity
must be kept.
It is reccomended always to ensure a minimum cooling
flow of 0.50 f/s.
Free Convection
Free convection is achieved when the diameter of the
borehole is at least 2" (~ 50 mm) bigger than the outer
diameter of the motor.
The motor should always be installed above the bore-
hole screen. If a flow sleeve is used, the motor can be
placed in the screen.
Calculation of the flow velocity:
Required data:
Q
min
: Flow in gpm
D
i
: Borehole diameter in inches
d
A
: Motor diameter in inches
Fig. 1
Drawing for cooling flow
TM
0
2
22
69
40
01
v
Qmin
2826 Di
2
dA
2
–
⎝ ⎠
⎛ ⎞
×
--------------------------------------------------
f /s =
N
D
motor
D
borehole
MS.book Page 10 Wednesday, January 26, 2005 3:25 PM