Xylem FHF SHF - Manual (Page 19)

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5. Installation
Use a sling for safe lifting and handling as shown in fig. 4, page 90. Do not use the eyebolts on
the motor as they are not designed to bear the weight of the entire unit.
5.1 Working position
The pump must be installed horizontally.
5.2 Positioning
Install the pump allowing adequate clearance for inspection and maintenance. Make sure that there are no
obstacles to the free circulation of the motor cooling air through the fan.
5.3 Foundation and anchoring
The foundation has to be strong enough to absorb the vibrations and rigid enough to keep the unit
properly aligned. Provide a concrete foundation, equipped with suitable holes (see overall dimensions
drawing) for the foundation bolts, to be covered with a final concrete cast. Smaller units of limited weight
may be simply anchored to the floor by means of foundation bolts (fig. 5, page 90). Larger units must be
anchored to the foundation in the following manner: place the unit on the foundation and fit shims or
metal wedges next to the foundation bolts. The unit must be positioned horizontally and levelled with the
help of a water level placed on the shaft or delivery flange (fig. 6, page 90). If the distance between the
two anchoring points exceeds 800 mm, additional shims must be used (fig. 7, page 90).
Between the rough surface of the foundation and the base leave a clearance of 25 ÷ 50 mm for the final
concrete cast. When the concrete has set (min 48 hours), tighten the foundation bolts uniformly.
5.4 Aligning the unit
Check the coupling before starting the pump.
Remove the coupling protection and loosen the screws of the support foot to avoid any stress or shifting of
the unit's height. Use a thickness gauge or comparator to check the angle alignment, then make sure that the
distance between the semi-couplings is the same along the entire periphery (fig. 8, page 90). Check the
parallel alignment with a ruler or comparator (fig. 9, page 90). The unit is aligned when the distance between
each shaft and the ruler, placed on the coupling, is the same at each of 4 opposite points. The maximum
axial and radial deviation between the two semi-couplings must not exceed 0.1 mm. If corrections are
needed, loosen or remove the screws in order to move the feet on the base and, if necessary, fit additional
calibrated shims or washers.
When the alignment (checked after tightening the screws) is completed, adjust the support foot on the base
surface and make sure it is fastened tightly to the base surface. First tighten the three screws between the
support and the base and then the screw between the support and foot. This way the alignment is not
disturbed by the support foot. Finally, reassemble the coupling protection.
5.5 Suction and delivery pipes
5.5.1 General
The internal diameter of the suction pipe must never be smaller than that of the suction port. The size of
the pipe will depend on the suction conditions. Bear in mind that the maximum theoretical suction lift is
reduced not only by the NPSH required by the pump, but also by the effects of the liquid temperature
and elevation and by the flow resistance in the suction pipe. Make sure that the unions in the suction pipe
are perfectly tight: if air leaks into the system the pump's operation will be negatively affected. Moreover,
in its horizontal sections, the suction pipe must slope slightly towards the pump and any restrictions must
be eccentric to avoid formation of air pockets. If the pump must operate with a negative slope on the suc-
tion side, install a foot valve at the end of the pipe to ensure and maintain proper priming. Install also a
non-return valve in the delivery pipe to protect the pump from excessive back pressure or reverse rota-
tion (after each stop). Depending on the system requirements, it may be advisable to fit an intermediate
flange (supplied on request) with a G
1 /
2
" connection between the pump flange and the pipe counterflan-
ge, to facilitate the filling and bleeding operations.
When the pipes have been connected to the pump, check the alignment as explained above.
WARNING
001073145_L_F_02-11:001073145_L_E_12-10 21-02-2011 16:44 Pagina 19