English (GB)
9
7.1.5 Expansion joints
Expansion joints are installed with the following purposes:
• to absorb expansions/contractions in the pipework caused by
changing liquid temperature
• to reduce mechanical strains in connection with pressure
surges in the pipework
• to isolate mechanical structure-borne noise in the pipework
(only rubber bellows expansion joints).
Fit expansion joints at a distance of minimum 1 to 1 1/2 times the
nominal flange diameter from the manifold on the suction as well
as on the discharge side. This prevents the development of
turbulence in the expansion joints, resulting in better suction
conditions and a minimum pressure loss on the discharge side.
Fig. 10
Examples of rubber bellows expansion joints without
and with limit rods
Expansion joints with limit rods can be used to minimise the
forces caused by the expansion joints. Expansion joints with limit
rods are always recommended for flanges larger than DN 100.
The pipework should be anchored so that it does not stress the
expansion joints and the pump. Follow the supplier’s instructions
and pass them on to advisers or pipe installers.
7.1.6 Pre-filling of diaphragm tank (if applicable)
If a diaphragm tank is connected to the system, prefill the tank
with nitrogen to a pressure of - 0.7 x setpoint.
7.2 Electrical installation
• The electrical installation of the booster system must comply
with enclosure class IP54.
• Make sure that the booster system is suitable for the power
supply to which it is to be connected.
• Make sure that the wire cross-section corresponds to the
specifications in the wiring diagram.
• If the system cannot be installed with the supply disconnecting
device located minimum 0.6 m above service level (ground
level), install the system with an external supply disconnecting
device made according to EN 60204-1, paragraph 5.3.2.
The system must be provided with a means permitting it to be
locked in the OFF (isolated) position. Furthermore, this device
must be installed in a position in accordance with EN 60204-1,
paragraph 5.3.4. Based on a risk assessment performed by
the installer/end-user, the system must, if required, be
connected to an external emergency stop device or an
emergency switching off device in accordance with the
requirements of EN ISO 13850.
Note
Expansion joints must not be installed to
compensate for inaccuracies in the pipework
such as centre displacement of flanges.
TM
02
49
81
19
02
-
TM0
2
4
9
7
9
1
9
0
2
Note
Use nitrogen to avoid corrosion.
Warning
The electrical installation must be carried out by
an authorised person in accordance with local
regulations and the relevant wiring diagram.
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