Pentax VP6A Instrucciones De Uso página 61

4. INSTALLATION

5 PIPE CONNECTION
WARNING!
Always make sure to use adequate pipes to the maximum operating pressure of
the pump (see pump plate). EXPLOSION HAZARD!
It is important for the delivery pipes not to cause abnormal pump loads.
High moments and forces transmitted by the pipes can give rise to misalignments
or damage the machine.
Constrain the pipes so as to avoid vibrations and/or displacements during opera-
tion.
The delivery pipes and their connected accessories must be bound so that the
weights, dynamic and thermal actions to not discharge forces and moments on the
pump flanges. We recommend using flexible couplings so as not to load the flanges
and prevent the spreading of any vibrations. Delivery pipes must have a diameter
equal to or greater than that of the pumps.
INCLINATION
2 % min.
WARNING!
The diameter of the pump flanges cannot be considered as pipe diameter, but
should be sized according to the system itself.
In case of very long pipes, provide expansion joints that can compensate any ther-
mal expansions.
The pipe flanges must be connected to the pump flanges in a parallel manner. To
avoid high pressure drops the fitting stubs with larger diameters must be built with
expansion angle of about 8°.
In case the delivery pipe has a greater diameter than the pump inlet, the connec-
tion must be made by a concentric reduction for upward delivery and eccentric for
lateral delivery. For the horizontal sections of the pipe, provide a minimum upward
inclination of 2% (Fig.36). If such indication is not possible, provide the pipe with
devices to prevent water hammer (air vent valves, water boxes). Provide a non-
return valve to isolate the pump from excessive pressures due to water hammer;
install a gate or needle type control valve downstream of the non-return valve.
WARNING!
Before the connection, the pipes must be thoroughly cleaned from any dirt or
foreign objects. If there are welded parts, remove all traces of slag.
Check the alignment of the pipe flanges with those of the pump. The two fac-
ing surfaces must be parallel, in axis and at the required distance from the
provided type of gasket.
Centre the gaskets between the flanges.
Tighten the flange bolts/tie-rods.
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