Xylem LN - Manual (Page 54)

Installation, Operating and Maintenance Instruction Model L, LN
Page 50
(optional, not delivered standard wise) can be
used. Levelling shims must be inserted next to the
foundation anchors and must lie plainly. After that
fasten foundation bolts symmetrically but only
slightly. Fill in base frame with non shrinking grout.
Notice:
 Avoid air bubbles (e.g. by vibrating).
 Check that the grout has properly set and
hardened.
 Take care for the after-treatment of the concrete
acc. to DIN 1045.
After setting, tighten the foundation anchor evenly and
firmly. Check alignment of coupling according chapter
5.3.1 and re-adjust, if necessary. Further check that all
screws between pump / motor and the base frame fit
snugly.
 If vibrations are transmitted to the foundation from
adjoining components, it must be guarded through
adequate vibration damping padding (vibrations
from outside can impair the bearing).
 To prevent vibrations being transmitted to
adjoining components, the foundation should be
laid on a suitable insulating base.
The size of these insulating pads will vary,
depending on circumstances, and should
therefore be determined by an experienced
specialist.
5.2 Connection of Pipings to the Pump
The pump must not be used as fixed point for
the piping. The permitted piping loads must not
be exceeded, refer to chapter 3.6.
5.2.1 Suction and discharge pipe
 The pipes must be of a size and design that liquid
can flow freely into the pump and that the pump
functions without problems. Particular attention is
to be paid to ensuring that suction pipes are
airtight and that the NPSH values are observed.
Under suction lift condition lays the suction pipe in
the horizontal section towards the pump so that it
is slightly inclined upwards so that no air traps
occur. Under positive suction head condition
install the suction pipe work slightly declined
towards the pump. Do not install fittings or elbows
right before the suction nozzle.
 If the suction supply is under vacuum and
entrained gas may be present in the liquid, it is
recommended that a vent line be considered
upstream of the pump suction with return to the
suction supply, above the max liquid level.
 An additional flushed piping - discharge branch-
vent line - makes it easier to de-aerate the pump
before start-up (pic 3).
pic 3
 When laying the pipes, make sure that the pump
is accessible for maintenance, installation and
disassembly.
 Notice "Permitted Forces on Flanges" (chapter
3.5).
 If expansion joints are used in the pipes, they
have to be supported in such a way that the pump
is not loaded unduly high because of the pressure
in the pipes.
 Before connecting up to pump: remove protective
coverings from suction and discharge branches.
 Before starting up, the pipe system, fittings and
equipment must be cleaned to remove weld
spatter, scale etc. Any pollutants are to be
completely removed from pump units that are
directly or indirectly connected to drinking water
systems before being installed and taken into use.
 To protect the shaft sealing (especially mechanical
seals) against foreign impurities, it is
recommended that a sieve, 800 micron, is
installed in the suction/intake pipe when the motor
is being started up.
 If the pipe system is tested with the pump
installed, do not exceed the maximum permitted
casing pressure of the pump and/or shaft sealing
(see data sheet).
 When emptying the pipe after the pressure test,
make sure that the pump is treated properly
(danger of rust and problems when starting up).
 In the case of pumps with stuffing boxes, replace
packing after pressure test (packing may be over-
compressed and thus no longer suitable for use).
5.2.2 Additional connections
The following additional connections are available:
Connection Description Dimension
E Pump drain R3/8"
LA Leakage R1/2"
M Pressure gauge R1/4"
V*) Vacuum gauge*) R1/4"
*) ... optional, drilled on request