Wilo DPL N Series, Installation And Operating Instructions Manual

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Depending on the operating condition of the pump
and/or installation (fluid temperature) the entire pump
can become very hot.
Avoid touching the pump
owing to the risk of burning.
– Check direction of rotation to conform with arrow indication
by briefly switching on the power supply. If necessary to cor-
rect, change any two of the incoming phases.
7. Maintenance
7.1 Mechanical seal
Slight dripping is likely to occur during the initial run-in period.
A visual leakage check should, however, be carried out from
time to time in order to forestall full failure and ensure in-time
exchage of the seal. WILO offers a repair set containing all parts
required for an exchage.
Exchange of mechanical seal, Version with IEC-motor
(Fig. 1)
Removal:
– Switch off power supply to pump motor and secure against
unauthorized switching on.
– Close isolating valves at both pump ports,
– Remove terminal wiring, if cable too short,
– Remove setscrews of shaft coupling (Item12),
– Remove motor flange bolts (Item 13/14) and lift off motor,
– Remove adapter flange bolts (Item 11) and remove adapter
with stub shaft and seal,
– Remove circlip (Item 7) at impeller shaft end,
– Remove impeller (Item 2) from stub shaft,
– Remove distance ring (Item 6) from stub shaft,
– Remove rotating seal parts (Item 5) from stub shaft,
– Remove stub shaft from adaptor
– Remove stationary seal ring from its seat in the adapter and
thoroughly clean seat face,
– Thoroughly clean seating part of stub shaft. If the shaft is da-
maged it must also be replaced.
Re- Assembly:
– Refit new stationary ring,
– Refit stub shaft into adaptor,
– Refit new rotating seal parts (Item 5) onto stub shaft,
– Refit distance ring (Item6) onto stub shaft,
– Refit impeller (Item2) to stub shaft,
– Fit new circlip (Item7) at impeller shaft end,
– Fit new O-ring gasket (Item8),
– Fit adapter complete with impeller and rotating seal into pump
housing and secure with holding- down bolts,
– Remout motor and secure with flange bolts (Item 13/14),
– Slide assembly fork (Item. A) between lantern and stub shaft.
The assembly fork must fit tightly.
– Fit shaft coupling to shaft ends and secure with setscrews
(Item 12),
lock the setscrew with adhesive (for example adhesive LOCK
AN 302 WEICON)
Tightening torque:
ENGLISH
9
Thread min. screw length
DN 40 DN 50 / DN 65
Flange connection PN 6 M12 55 mm 60 mm
Flange connection PN 10 M16 60 mm 65 mm
5.2 Electrical wiring
Electrical work to be carried out ba a qualified and li-
cenced electrician in strict conformity with ruling re-
gulations.
– Check that the power supply is suitable, conforming with the
data on the pump rating plate.
– Power supply: 3~400/415 V, 50 Hz,
– Network fuse: 16A, inert action,
– Observe earthing regulations.
– Cable leads to be routed in such a way to avoid contact with
pipework and/or pump/motor housings.
– A wiring diagram for the power wiring is inside of the termi-
nal box cover.
– The use of thermal overload protection is recommended.
6. Commissioning
6.1 Filling and venting
– The system must be filled and ventilated properly.
– To avoid noise and damage resulting from cavitation, it is im-
portant to ensure a minimum inlet pressure at suction port of
the pump. The minimum inlet pressure depends on the loca-
tion and point of operation and must be determined accor-
dingly. Considerable parameters in determining the minimum
inlet pressure are the NPSH value of the pump at its opera-
tion point and the steam pressure of the flow medium.
– Bleed pumps by loosening the ventilation valves (Fig. 1, 2,
item 9).
Dry-running will destroy the mechanical seal.
Depending on the fluid temperature and the system
pressure, if the vent screw is completely loosened hot
liquid or gas can escape or even shoot out at high
pressure.
Beware of scalding.
ATTENTION!
When displacing fluids from a tank it is imperative
to maintain at all times sufficient suction head in or-
der to avoid dry-running!
For units which are be insulated, only the pump-
housing may be insulated. The motor and the lan-
tern must remain free from blockages.
ATTENTION!
ATTENTION!
– Remove assembly fork
– Rewire power leads to motor terminals,
– Open isolating valves at both pump ports,
– Restore power supply,
– Repeat measures as for commissioning (Chapter 6).
screw tightening torque
M 6 8 Nm
M 8 20 Nm
M 10 30 Nm
In the event of incorrect assembly the screw
nut may become locked in the oblong hole.
This may adversely influence the operatability
of the flange connection due to the inadequate
tension of the screws.
3. It is recommended to use screws for flange connections of
property class 4.6. if screws of higher properties are used
for the assembly only the torque according to property
class 4.6 is permissible.
Permissible torque of property class 4.6.:
for M12
f 40 Nm
for M16 f 95 Nm
If screws of higher property classes are used,
splintering may occur around the edges of the
oblong holes due to the higher screw tensions.
This will cause the screws to lose their tension
and the flange connection may become leaky.
4. Screws of sufficient length must be used
ATTENTION!
ATTENTION!