Grundfos Fire NKF 150-400, Инструкция по установке и эксплуатации

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5.1.3 Vibration dampening
To prevent vibrations from being transmitted to the building and
pipework, we recommend that you fit expansion joints and
vibration dampers. See fig. 16.
Fig. 16 Vibration dampening
Expansion joints
Expansion joints provide the following functions:
• Absorption of thermal expansion and contraction of pipework
caused by variations in liquid temperature.
• Reduction of mechanical influences in connection with
pressure surges in the pipework.
• Isolation of structure-borne noise in the pipework (only rubber
bellows expansion joints).
Fit the expansion joints both on the suction and the discharge
sides. The distance from the pump should be at least 1 - 1½ x DN
diameter. This prevents turbulence in the joints and ensures
optimum suction conditions and minimum pressure drop on the
discharge side.
At high water velocities (> 5 m/s), we recommend that you fit
larger expansion joints matching the pipework.
Vibration dampers
To prevent vibrations from being transmitted to the building, we
recommend that you isolate the pump foundation from buildings
by means of vibration dampers.
To select the correct vibration damper, the following details are
required:
• Forces transferred through the damper.
• Engine speed.
• Desired dampening in % (recommended value: 70 %).
The selection of vibration damper differs from installation to
installation. A wrong damper may, in certain cases, increase the
vibration level. Vibration dampers should therefore be sized by
the supplier.
If the pump is installed on a foundation with vibration dampers, fit
expansion joints on both sides of the pump. This prevents the
pump from "hanging" from the flanges.
5.1.4 Pipework
The pipes must be of an adequate size, taking the pump inlet
pressure into consideration.
Install the pipes so that air locks are avoided, especially on the
suction side of the pump. See fig. 17.
Fig. 17 Installation of pipes
Secure the pipes close to the pump on the suction and discharge
side with pipe brackets attached to the building (wall, ceiling,
floor). See fig. 18.
The pipes should lie true against the pump flanges without being
stressed. Otherwise, the pump may be damaged.
Fig. 18 Fixing points of the pipes
Isolating valves must be installed on suction and discharge sides
of the pump.
5.1.5 Fresh air supply
Fig. 19 Ventilation of the site
If necessary, install blinds on-site that open as soon as the
engine starts. This will ensure an adequate fresh air supply and
removal of engine heat.
TM
03
7
7
80
49
06
Caution
Do not fit expansion joints to make up for
inaccuracy in the pipework, e.g. centre
displacement or misalignment of flanges.
Vibration
damper
Expansion joint
Caution
The pipework must not stress the pump housing
or transfer any forces to the pump housing. Non-
compliance may damage the pump. Permitted
flange forces and torques. See section
4.4.2 Pump.
T
M
00
22
63
33
9
3
TM
03
77
75
49
06
T
M
03
5
5
0
1
37
06
0 90 90 80 80 10 10
20 20 30 30 40 40 60 60
70 70
50 50