Suction Pipe; Delivery Pipe - Calpeda MXV 25 Originalbetriebsanleitung

which are harmful or have to be removed at temperatures
higher than 60 ˚C).
Make sure prolonged accidental leakage of liq-
uid does not cause damage to persons or
property.
Leakage may develop as a result of surge pressure or
water hammer, erroneous operations (such as failing to
close a plug or valve) or other functional disorders. Allow
for the possibility of channeling away any leaked liquid or
for an automatic drainage system against flooding.
Mount the pump on a flat horizontal surface (using a level
gauge) such as a solid cement base or a rigid supporting
structure in metal.
To ensure stability, insert, if necessary, small pieces of
calibrated metal plate next to the 4 anchoring screws.
4. Connecting the motor (only MXV(L), MXV(L)4)
The MXV(L), MXV(L)4 pumps are designed for use with
standard electric motors with (IEC 34-7) IM V1 construc-
tion form and dimensions and output ratings in accor-
dance with IEC 72.
If a pump is supplied without the motor, check the rat-
ed power and rpm indicated on the name plate and tech-
nical data given in the data sheet.
ATTENTION: the motors must have two lifting points
in diametricalIy opposite positions for vertical lifting with
the shaft end downwards (fig.1 b)
Before installation clean the motor shaft extension, the
key and contact surfaces of the flanges to remove any
protective paint, dirt or oxydation.
Lubricate the motor shaft extension with a graphite-
base, dripfree, anti-friction product.
Do not use oil as it can harm the mechanical seal below
(see section 9.1.).
With the pump in the vertical position, insert the motor
shaft in the coupling, aligning the key with the key slot
and resting the motor flange on the lantern flange.
Turn the motor, adjusting the position of the terminal
box as required and aligning the holes on the flanges.
ATTENTION: the 4 flange screws (70.18) with nut
must be uniformly tightened with alternated crossover
tightening procedure in diametrically opposite positions
(see section 10.1.).
Before and after tightening the screws (70.18), make
sure the coupling with pump shaft and motor shaft
can be freely turned by hand (remove and then replace
the guard 32.30).
ATTENTION: for removing or replacing the motor
see section 9.
5. Pipes
Provide a diameter assuring a liquid flow velocity not
higher than 1.5 m/s for suction, and 3 m/s for delivery.
The pipe diameters must never be smaller than the
pump connection ports.
The arrows on the pump casing (14.00) indicate the in-
let (suction) and outlet (delivery) ports.
Ensure the internal pipe surface is clean before connec-
tion.
Secure all pipes to their rests close to the pump and con-
nect them so that they are not subjected to stress and
do not transmit vibration or flexion strain to the pump
(see fig.2).
Provide for the possibility of draining the pump
without having to drain the entire system.
Install correctly any compensators for absorption of ex-
pansion or impeding noise transmission.
Make sure gaskets do not protrude inside the pipes for
the pump types MXV-B, MXV(L) 25,32,40 and MXV(L)4
25,32,40 screw the union couplings or the flanges into
the threaded ports (ISO 228) by inserting in the joint a
suitable sealing material.
Tighten the pipes or union couplings only to the extent
sufficient to ensure a tight seal. Excessive torque may
damage the pump.
With flanged ports make sure the gaskets do not pro-
trude inside the pipes.
Fig. 2 Systems diagram
A = Suction lift operation
B = Positive suction head operation
4
5
B
5 1
A
2
1

5.1. Suction pipe

When a pump is located above the water level (suc-
tion lift operation, fig. 2 A), fit a foot valve with a strainer,
which must always remain immersed.
The suction pipe must be perfectly airtight and be led up-
wards in order to avoid air pockets.
When the liquid level on the suction side is above the
pump (inflow under positive suction head, fig. 2 B), fit a
gate valve.
Follow local specifications if increasing network pressure.
Install a strainer on the suction side of the pump to
prevent foreign particles from entering the pump.

5.2 Delivery pipe

Install a gate valve in the delivery pipe to regulate flow-
rate, head and absorbed power.
Install a pressure gauge between the pump and the gate
valve.
ATTENTION: install a check valve between the pump
and the gate valve in order to avoid reverse flow after
switching off the pump unit and to protect the pump from
water hammering.
With servo-operated shut-off devices, provide an air ves-
sel or other protection device against surge of pressure in
the case of sudden changes of flow rate.
12
5
3.93.113
7 7
1. Strainer
2. Foot valve
3. Check valve
4. Bypass valve
5. Gate valve
6. Pressure gauge
7. Supports and clamps for
pipelines
5
3
6