Grundfos NK Montage- Und Betriebsanleitung Seite 19

6.2 Foundation and grouting of horizontally mounted
NK, NKG pumps with base frame
We recommend that you install the pump on a plane and rigid
concrete foundation which is heavy enough to provide permanent
support for the entire pump. The foundation must be capable of
absorbing any vibration, normal strain or shock. As a rule of
thumb, the weight of the concrete foundation should be 1.5 times
the pump weight.
The foundation should be 100 mm larger than the base frame on
all four sides. See fig. 8.
Foundation, X = min. 100 mm
Fig. 8
The minimum height of the foundation (h
×
m 1.5
pump
h
= ------------------------------------------- -
f × × δ
L B
f f concrete
The density (δ) of concrete is usually taken as 2,200 kg/m³.
Place the pump on the foundation, and fasten it. The base frame
must be supported under its entire area. See fig. 9.
Correct foundation
Fig. 9
) can then be calculated:
f
Fig. 10 Incorrect foundation
Fig. 11 Base frame with pouring holes
It is important to prepare a good foundation prior to the
installation of the pump.
NK, NKG pumps with base frame are always prepared for
grouting.
For 2-pole NK, NKG pumps with large motors, grouting of the
base frame is mandatory in order to prevent vibration energy from
the rotating motor and liquid flow to evolve.
Grouting is mandatory for NK, NKG pumps with base frame and
the following 2-pole motor sizes:
50 Hz
55
75
110
132
160
200
250
315
355
For pumps with motor up to and including 45 kW and for all
pumps with 4- and 6-pole motors, grouting is only to be seen as
an option.
Steps
There are five steps:
1. Pouring of foundation
2. Shimming of base frame
3. Preliminary alignment
4. Grouting
5. Final alignment according to section 6.3 Alignment.
kW
60 Hz
55
75
110
132
160
200
250/280
315/353
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