POMPE CUCCHI Series WPP Operating instructions

Serie WPP, WPL
GEAR PUMP
OPERATING AND MAINTENANCE MANUAL
POMPE CUCCHI
s.r.l.
POMPE CUCCHI s.r.l.
20090 Opera (MI) - ITALY
Via dei Pioppi, 39
Tel.[phone] (R.A.)
Fax [phone]
e-mail: [e-mail]

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CONTENTS
1. GENERAL INFORMATION .........................................................................................................25
1.1 SUPPLY CONDITIONS...................................................................................................25
1.2 MANUFACTURER..........................................................................................................25
1.3 USER MANUAL CONTENT ............................................................................................25
1.4 NAME, TYPE ..................................................................................................................26
1.5 NOISE EMISSIONS ........................................................................................................26
1.6 APPLICATION FIELDS AND LIMITS. ALLOWED AND NOT ALLOWED USES..............26
2. TRANSPORT, HANDLING, PACKAGING, STORAGE...............................................................27
3. DESCRIPTION OF THE PUMP AND THE PUMP UNIT.........................................................................27
3.1 GENERAL DESCRIPTION OF THE MACHINE...............................................................27
3.2 WARNINGS ....................................................................................................................27
3.3 PROTECTION DEVICE ..................................................................................................28
3.4 ADDITIONAL DESCRIPTION OF ACCESSORIES .........................................................28
3.4.1 Seal parts............................................................................................................28
3.4.2 Safety valve ........................................................................................................28
4. INSTALLATION, ASSEMBLY.....................................................................................................29
4.1 SPECIAL ASSEMBLY TOOLS........................................................................................29
4.2 INSTALLATION SITE INFORMATION ............................................................................29
4.2.1 Space requirements for operation and installation...............................................29
4.2.2 Inspection before starting installation ..................................................................29
4.2.3 Foundation details...............................................................................................29
4.2.4 Alignment requirements ......................................................................................29
4.2.5 Suction lift ...........................................................................................................29
4.3 INITIAL INSTALLATION..................................................................................................31
4.3.1 Complete Pump Unit ...........................................................................................31
4.3.2 Free shaft pump..................................................................................................31
4.4 DRIVE UNIT AND ACCESSORY ASSEMBLY ................................................................32
4.4.1 Motor ..................................................................................................................32
4.4.2 Installation of safety and control devices .............................................................32
4.5 ELECTRICAL CONNECTIONS, CONNECTION CABLES ..............................................32
4.6 PIPING............................................................................................................................32
4.6.1 General ...............................................................................................................32
4.6.2 Forces and moments which operate on suction and delivery flanges. .................32
4.6.3 Fastening screw torques .....................................................................................33
5. COMMISSIONING, OPERATION, SHUTDOWN .........................................................................33
5.1 DOCUMENTATION ........................................................................................................33
5.2 PUMP PREPARATION FOR STARTUP .........................................................................33
5.2.1 Filling / discharge ................................................................................................33

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5.2.2
Electrical connections .........................................................................................33
5.2.3 Verifying the direction of rotation .........................................................................33
5.3 SAFETY DEVICES .........................................................................................................33
5.3.1 Mechanical safety devices (guards for rotating parts)..........................................33
5.3.2 Acoustic insulation ..............................................................................................34
5.3.3 Splash-proof cover..............................................................................................34
5.3.4 Regulation on the electric components................................................................34
5.4 COMMISSIONING ..........................................................................................................34
5.4.1 Initial commissioning ...........................................................................................34
5.4.2 Startup after shutdowns ......................................................................................34
5.4.3 Pump system requirements.................................................................................35
5.4.4 Startup/shutdown frequency................................................................................35
5.4.5 Operation and startup with closed valve..............................................................35
5.5 SHUTDOWN...................................................................................................................35
5.5.1 Decommissioning................................................................................................35
5.5.2 Emptying.............................................................................................................35
6. MAINTENANCE AND INSPECTION ...........................................................................................35
6.1 USE PRECAUTIONS......................................................................................................35
6.2 WEARABLE MATERIALS ...............................................................................................36
6.3 SURVEILLANCE DURING OPERATION ........................................................................36
6.4 PREVENTIVE MAINTENANCE.......................................................................................36
6.5 PUMP DISASSEMBLY AND REASSEMBLY ..................................................................36
6.5.1 Tools...................................................................................................................36
6.5.2 Disassembly/reassembly procedure....................................................................36
7. FAULTS: CAUSES AND SOLUTIONS .......................................................................................40
8. WARRANTY CONDITIONS ........................................................................................................42
9. ALLEGATI/ANNEXES ................................................................................................................43

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1. GENERAL INFORMATION
1.1 SUPPLY CONDITIONS
According to agreements with the Customer, the pump can be supplied either as bare shaft
or pump unit. By pump unit we mean the pump coupled with the motor, including reduction
gears and/or speed variators, if any. The coupling can be direct (WPP series, only for bare
shaft pumps) or through bell housing (WPL series).
1.2 MANUFACTURER
The pump Manufacturer is POMPE CUCCHI S.R.L.. You can apply for assistance by send-
ing a request to the following address:
Via dei Pioppi 39 - 20090 OPERA (MI) ITALY
Tel. [phone] (Hunting Line)
Fax [phone]
E-mail : [e-mail]
1.3 USER MANUAL CONTENT
This user manual provides all the necessary information to ensure a safe and correct use of
the machine. It was written – when applicable – according to point 5.5 of Standard EN 292
part 2-1992 - Machinery Safety; according to point 7 of Standard UNI EN 809-2000 Pumps
and Pump Units for Liquids - Common Safety Requirements - and according to point 1.7.4 of
Directive 98/37/EC 1998 (ex 89/392 EC). In this manual it is constantly referred to safety in-
structions. Such instructions are identified by the following symbols:
It represents the safety instructions contained in this manual,
whose non-observance may compromise safety.
It is shown when electrical safety is essential to worker protection.
It indicates the safety instructions which should be taken into ac-
count for the safe operation of either the pump, the pump unit or
the pump or pump unit protection.

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1.4 NAME, TYPE
The pump standard execution is that with brass body, AISI 316 shafts, AISI 316L gears and
shafts, bearing bushes in graphite and ceramic/graphite/NBR mechanic seal. The complete
series covers different executions (AISI 316 body, gears in KK plastic) and different capaci-
ties. Moreover, executions with special mechanic seal or magnetic drive are also provided.
The pump identification is realized through an alphanumeric code (see the following exam-
ple):
- 0WLZ008/NZPFB00: pump type WPLZ, brass execution, rated capacity 8 l/min. at 1500
rpm (displacement 6,2 cm3/rev), shafts made of stainless steel, a gear in KK plastic, stan-
dard mechanic seal, equipped with brass safety valve, with bell housing for coupling with a
Size 80 motor.
1.5 NOISE EMISSIONS
- Reference standard: CEN/TC 197/SC3 N 21 E -fig.8- ISO 3744 on 6 positions
- Measured values:
1 - Equivalent weighted continuous acoustic pressure level
Leq = 80 dB(A);
2 - Maximum weighted instantaneous acoustic pressure
C (peak level) Lpc < 82 dB(C).
- Test conditions: When measuring noise, the pumped liquid (ref. to oil with 30 cP viscosity)
must be introduced into the testing system at a speed of less than 0.8 m/s into pipes. It
must however reach laminar flow regime (thus the speed must be related to the viscosity)
and the conditions outlined in this manual must be respected.
1.6 APPLICATION FIELDS AND LIMITS. ALLOWED AND NOT ALLOWED
USES
Each machine shall be used according to the type of application, operating conditions and
liquid characteristics provided in contract specifications. Each variation which alters the in-
tended use of the pump is forbidden and the User is fully responsible for it (e.g. the use of a
liquid which is corrosive to pump materials rather than the recommended fluid, etc.). For
variations in use within the application limits (e.g. fluid viscosity variations) it is advised to
contact the Manufacturer in advance.
The maximum operating pressure, for pumps in standard execution, is of 15 bar.
In any case, the use of “KK” or alike plastic gears to allow the pump to operate also
with poorly lubricating fluids, requires greater attention to avoid excessive or unex-
pected pressure loads.
It is absolutely forbidden to use the machine in hazardous environments (explosive
atmosphere, etc…), the use of hazardous substances (e.g. fluids with dangerous
gases), in critical conditions (e.g. abnormal temperatures, etc…), which are not sup-
plied with the pump.
For pumps and pump units intended to be used in potentially explosive environ-
ments, please read carefully “Additional instructions for the operation and manage-
ment of pumps and pump units intended to be used in potentially explosive atmos-
pheres (Directive 94/9/EC)”. In case of slipping of the magnetic coupling, the surface
temperature can reach 350°C in a few seconds; therefore, it is necessary to provide a
continuous monitoring of the temperature near the coupling.
Pompe Cucchi S.r.l. declines every responsibility for the consequences arising from an im-
proper use of the machine which does not comply with what prescribed in this manual or
specifically requested when ordering.

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2. TRANSPORT, HANDLING, PACKAGING, STORAGE
Pompe Cucchi sells “ex works”. Consequently, transport from the manufacturing shop to the
named place of destination is carried out by the Customer under his own responsibility. For
each transport a suitable standard packaging is ensured or established based on Customer
requirements who, in any case, must give information about the type of shipment to be per-
formed (by land, air, “overseas“).
In case of long stationary periods under critical environmental conditions (such as: high hu-
midity and/or salinity, etc.) the supply shall be stored in a protected environment.
3. DESCRIPTION OF THE PUMP AND THE PUMP UNIT
3.1 GENERAL DESCRIPTION OF THE MACHINE
Essentially the pump consists of two driven pinions which mesh one another inside a cast
main body, thus creating a flow of liquid between the inlet and the outlet.
The fluid containment inside the pump is ensured by a suitable seal part as defined in the
order.
Pumps, series WPL are connected to the motor (shape B34), according to CE standards, by
means of a flexible (or magnetic) coupling and a bell housing, which also acts as safety
coupling guard.
The pump unit series WPL can be equipped with a mechanic reduction gear or a hydraulic
variator to adjust the rotation speed, according to CE standards.
3.2 WARNINGS
Standard construction pumps, as an indication, require a NPSH of approx. 0.4 bar. Always
calculate the maximum available suction lift, in relation to fluid characteristics, suction circuit
and operating conditions. Ensure that gears do not operate when dry. Before starting the
pump for the first time or after long stationary periods, it is advisable to fill the gear spaces
with oil or liquid being pumped through one of the nozzles and rotate the driving shaft by op-
erating manually with a screwdriver on the motor cooling fan. This also makes it possible to
check for even and smooth movement of rotary components and excessive friction. It is rec-
ommended that an overland cut-out set at approx. 10% above the motor current be installed
in the control circuit.
INLET
OUTLET

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In our pumps the direction of rotation is clearly shown by an arrow marking the right direc-
tion.
The pump operating temperature in normal working conditions is about 80°C. In special
pump versions, working temperatures of 180°C and more may be achieved. To protect per-
sonnel from dangers due to the temperatures reached during the operation of the machine,
in the event of accidental contact (burn), the User must reduce the external pump tempera-
ture by means of insulation plates, coatings, screens, barriers, etc. As limit reference tem-
perature for the contact surface it is advisable to take 55°C. Below this value, for hot smooth
surfaces in bare metal, there is no burn threshold. For a detailed knowledge of this problem
in relation to different particular cases, the User can read the standard UNI EN 563 Ed.’94,
where burn thresholds are specified for several types of surface according to the “surface
temperature - contact time” parameters.
Liquids to be pumped must not contain abrasive or solid suspension as this will greatly re-
duce the pump life. At this purpose we recommend the installation of a properly sized filter
on the suction line if solids may be present.
When pumps are installed in parallel, the suction lines should be adequately separated to
prevent unnecessary turbulence.
3.3 PROTECTION DEVICE
The bell housing installed by the Manufacturer is made of an aluminium die-casting, fas-
tened to the motor by screws, duly shaped to prevent fingers from coming into contact with
moving parts. It can be removed only by using a proper tool.
3.4 ADDITIONAL DESCRIPTION OF ACCESSORIES
3.4.1 Seal parts
The pump is usually supplied equipped with mechanical seal. If the Customer requires a
particular type of seal, Pompe Cucchi S.r.l. installs the desired seal after verifying if its di-
mensions are compatible with those of the pump. In case the Customer requires only the
seal mark, the Company leaves the Manufacturer to select the type of seal, by giving infor-
mation about the pumped liquid.
3.4.2 Safety valve
The pump can be equipped with a safety valve, with adjustable calibration, installed on the
front of the pump body.
After reaching the calibration pressure, prevailing on the contrast spring reaction, the valve
starts opening by connecting the outlet side and the inlet side of the pump.
The valve function is just to protect the pump from accidental pressure peaks. Its prolonged
opening may imply the pump damaging.

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4. INSTALLATION, ASSEMBLY
4.1 SPECIAL ASSEMBLY TOOLS
To assemble the pump you do not need special tools, except for seal extractors (see Main-
tenance).
4.2 INSTALLATION SITE INFORMATION
4.2.1 Space requirements for operation and installation
The space destined by the Customer to the installation of the machine should be enough to
gain access to, install and maintain the pump unit.
4.2.2 Inspection before starting installation
Before installation, the Customer must ensure that the environmental conditions of the se-
lected site comply with requirements specified under the contract.
In particular, unless expressly required and accepted in the order, the installation site should
not be exposed to the following environmental conditions:
- abnormal temperature;
- high humidity;
- corrosive atmosphere;
- explosion and/or fire hazard areas;
- dust, sandstorms;
- earthquakes and other similar external conditions;
- high level of vibrations;
- high altitude;
- flood hazard areas.
4.2.3 Foundation details
When the pump unit is installed, it shall be firmly fixed in place by fastening bolts or by using
other securing methods.
Ground fastening bolts or other securing methods shall be of sufficient strength to prevent
the pump unit from moving accidentally.
4.2.4 Alignment requirements
The alignment operation must not submit the pump unit to axial and radial stress, therefore
the offset must always be lower than the tolerance limits expected for the coupling.
Particular attention should be paid to the alignment of the assemblies equipped with a mag-
netic coupling.
4.2.5 Suction lift
The suction lift, that is the vertical distance between the pump inlet mid-point and the free
surface of the tank to which the pump is attached, must not exceed 5 m to allow pump prim-
ing and avoid cavitation phenomena.

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Otherwise, contact our Technical Department.
Each pump must have its own suction pipe; the installation of two or more pumps with a
common suction pipe length causes the pump to work less efficiently.
The length of the suction pipe must be reduced as much as possible to minimize pressure
losses in such segment; higher pressure losses in the discharge line do not adversely affect
the correct operation of the pump (if they do not exceed the delivery limits stamped on rating
plate).
Furthermore, it is necessary to check that siphons are not created in the suction pipe, since
the formation of air pockets generates vibrations and stresses which are not compatible with
the correct operation of the pump and may obstruct the pump priming at startup.
In case of installation below head, the pump does not ensure to be able to intercept the flow
of fluid as a shut-off cock or a proper stop valve.
NO
YES
NO
YES

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4.3 INITIAL INSTALLATION
According to the conditions of supply, the pump can be delivered as follows:
4.3.1 Complete Pump Unit
In this case the Customer must stiffly fasten the pump unit in order to ensure the correct axis alignment
in all operating conditions.
We recommend the use of vibration dampers below the motor feet and vibration damping
sections on pipes near pump inlets.
Once the pump unit has been positioned, proceed as described below:
a) connect suction and discharge pipes respectively to the pump inlet and outlet;
b) power the motor, by carefully controlling the compatibility of motor voltage and frequency with those
of the system;
c) open the intake and discharge pipe valves, if any;
d) run the motor for a while to verify that the pump rotates in the direction indicated by the arrow
stamped on the pump.
4.3.2 Bare shaft pump
In this case, before following the steps described at Paragraph 4.3.1, choose the type of mo-
tor and align it to the pump.
The motor must be selected by the Customer depending on the type of operation for which it
is specifically requested (continuous operation, discontinuous operation, repeated startups,
indoor or outdoor installation, explosive atmosphere, critical environmental conditions, alti-
tude, etc.) with power compatible with that required by the pump.
Motor and pump shafts are coupled by flexible or magnetic coupling. The aluminium bell
housing, with centerings both on pump and motor, guarantees a correct alignment.
In case of connection by magnetic coupling it is very important to avoid the generation of ax-
ial loads on the inner magnet, which can cause the premature wear of the bush shim ad-
justments, by leaving the outer magnet free to position itself axially. After connecting the
pump to the engine by the lantern, unscrew the fixing pin of the outer magnet on the crank-
shaft and retighten this last after the magnet has reached its balance position.
While centering the outer magnet, pay special attention to the effects of the magnetic
pull force; in particular beware of fingers (always use safety gloves). Be careful not to
damage magnets by accidental shocks.
You are recommended to use tools in non-magnetic material.

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4.4 DRIVE UNIT AND ACCESSORY ASSEMBLY
4.4.1 Motor
The Company installs EC approved electric motors, of power compatible with that required
by the pump, selected according to the desired operating conditions and environmental
characteristics. In particular if the pump unit is required to operate in explosive atmosphere,
the motor is chosen in explosion-proof execution (we remind that, to be used within the
European Union, also the execution of the pump and the relevant fittings must com-
ply with directive 94/9/EC).
4.4.2 Installation of safety and control devices
If specifically requested in the order form, the Company provides the relief valve, which must
be calibrated to protect the pump from damage. Once it has been properly calibrated, the
valve must not be tampered with in any way, since volumetric pumps can reach quickly, with
the delivery closed, extremely high pressure values, with consequent very serious danger.
Any pressure adjustment shall be compulsorily made with the pump stopped and de-
pressurized.
The User shall install a pressure gauge in the pump outlet; it is advisable to install a vacuum
gauge near the pump inlet.
In case also a regulating valve is installed on the system, make sure that the calibration
pressure differs considerably from the safety pressure not to generate dangerous resonance
phenomena (pipe and/or valve break).
4.5 ELECTRICAL CONNECTIONS, CONNECTION CABLES
The machine shall be connected to the external ground protection system by the appropriate
terminal, which must be identified by the PE letter. Connection cables shall be properly sized
and insulated. Before energizing the machine, always verify that the mains voltage and fre-
quency are compatible with those of the motor.
4.6 PIPING
4.6.1 General
Pipes shall have a suitable diameter to allow a regular flow with low pressure losses. There-
fore, we recommend to use, at least for the suction line, pipes with inner diameter equal to
or greater than that of the pump inlet, mostly when the viscosity level becomes considerable.
To minimize pressure losses in the circuit, we recommend to avoid, as much as possible,
abrupt variations of section and direction (curves) along the pipe run, particularly in the suc-
tion line.
4.6.2 Forces and moments which operate on suction and delivery flanges.
As general rule it would be necessary to interpose flexible vibration damping sections be-
tween the pump and the system piping; therefore, we recommend to verify that the flanges
of the connection pipes are always placed, in free position, with the planes parallel to those
of the flanges of the suction and delivery nozzles to avoid that, after fastening them, forces
and moments of excessive value are generated.
In any case, the User shall make sure that the loads induced on the pump flanges, under the
most critical operating conditions, do not exceed the values prescribed by Standards UNI
EN ISO 14847.

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4.6.3 Fastening screw torques
The fastening torque for the screws of our pumps shall be:
- for M6 screws 11-12 Nm
- for M8 screws 20-22 Nm
- for M10 screws 38-40 Nm
For more detailed information, contact our Technical Department.
5. COMMISSIONING, OPERATION, SHUTDOWN
5.1 DOCUMENTATION
Operating and maintenance manual
5.2 PUMP PREPARATION FOR STARTUP
5.2.1 Filling / discharge
To prevent gears from running dry, before starting the pump for the first time or after long
stationary periods it is advisable to fill the gear spaces with oil or liquid being pumped
through one of the nozzles and rotate the driving shaft by operating manually with a screw-
driver on the motor cooling fan. This also makes it possible to check for even and smooth
movement of rotary components and excessive friction.
The pump discharge, in case of toxic, noxious or, in any case, dangerous fluid, shall take
place according to all the necessary cautions. In particular, the pump body shall be emptied
according to proper operating maneuvers.
5.2.2 Electrical connections
It is necessary to choose wires which satisfy the operating conditions required by the Cus-
tomer (e.g. voltage, current, electric shock protection, bundle of cables) and can support ex-
ternal influences (e.g. ambient temperature, presence of water or corrosive substances, me-
chanical stresses, fire hazards). Moreover, we remind that wires must be properly sized to
ensure the voltage drop from the power supply inlet to the point of load application does not
exceed 4%.
5.2.3 Verifying the direction of rotation
Open the intake and discharge valves. To verify the direction of rotation run the motor for a
while only to check that the pump rotates in the direction marked by the arrows.
5.3 SAFETY DEVICES
5.3.1 Mechanical safety devices (guards for rotating parts)
The hazardous area, represented by the projecting sections of pump side and motor side
shafts and the coupling, shall be protected against accidental contact using bell housing,
which must be firmly secured both to the motor and to the pump.

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5.3.2 Acoustic insulation
Sound emission values are specified in this manual. The User should always verify if the
regulations of his own country prescribe, in relation to the frequency of exposure to emission
values, the use of individual protection devices. If it is, he must comply with the require-
ments contained in the above-mentioned regulations to protect the operator’s health and
safety.
5.3.3 Splash-proof cover
In the event the liquid being pumped is dangerous, the operator must be in any case pro-
tected against the risk of any accidental contact with jets of liquid by wearing appropriate in-
dividual protection devices.
5.3.4 Regulation on the electric components
We remind that in accordance with Standard EN 60204-1 Ed1998-04, as power disconnect-
ing switch, a plug/socket combination is allowed for a machine with rated power equal to or
lower than 16 A and a total power equal to or lower than 3 kW.
5.4 COMMISSIONING
5.4.1 Initial commissioning
- Ensure that the pump unit is properly earthed.
- Verify that suction pipes are properly joined one another to avoid air infiltrations which
would prevent the pump from priming.
- Check that siphons are not created in the suction pipes so that pump can completely re-
move the air. In this case, if the air is not completely removed then the flow rate may de-
crease and the noise level may increase although the pump has taken in the liquid, with
consequent premature deterioration of bearing bushes and moving parts.
- Verify the proper operation of the relief valve; to do so it is necessary to gradually increase
pressure, by acting on the valve located on the discharge pipe, up to reach the expected
calibration value. Now, after a further rotation of the valve, the discharge pressure shall
remain lower than the calibration value. Otherwise, after stopping the machine and de-
pressurizing the pump, it is necessary to disassemble the valve cap 31, remove the
gasket below 30, loosen the nut 29and rotate counterclockwise the spring 17 pre-load ad-
justing ring nut 30 (clockwise to increase the pre-load). Retighten the lock nut 29, inter-
pose the gasket 30 and rescrew the protection cap 31. The adjusting ring nut 30 is not
equipped with retainer, therefore it is necessary to pay attention, when unscrewing
it, not to cause a leakage of the fluid being pumped.
5.4.2 Startup after shutdowns
The most common case in which the pump may stop working - apart from the power supply
failure (black out) – is when the electric motor overcharge protection comes into operation.
In this case, before starting the pump examine the causes which triggered the activation of
the protection and remove them.
In magnet drive pumps, it may happen that, when the maximum torque value that can be
transmitted is exceeded, the pump stops while the engine runs idle. In this case you need to
stop immediately the engine, wait until the magnet “bell” of the inner magnet is cooled (the
heating of this last is due to the effect of eddy currents), and restart the engine after eliminat-
ing the causes of the failure.

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5.4.3 Pump system requirements
In volumetric pumps, pressure is not related to flow rate and/or rotation speed; therefore,
avoid installing shut-off valves on the discharge pipe and, in any case, between the pump
and the stop valve a relief valve must always be installed.
5.4.4 Startup/shutdown frequency
Pumps which are expressly requested by the Customer to start frequently and repeatedly do
not show any problems for this kind of operation.
5.4.5 Operation and startup with closed valve
It is forbidden to start the pump with the discharge valve closed: such mistake would
cause an abrupt pressure rise above the limit values with consequent seizing.
5.5 SHUTDOWN
5.5.1 Decommissioning
In case of decommissioning of the pump unit, it is necessary to disconnect the power supply
to make unexpected and accidental startups impossible.
5.5.2 Emptying
A pump or a pump unit which operates with a flammable, toxic, corrosive or, in any way,
hazardous fluid, or with a liquid at a temperature higher than 55°C, shall be equipped with a
device such as a connection pipe, to be provided by the User, to collect and dispose the
liquid drained or coming from any possible leakage from the shaft seal or discharged by a
pressure relief valve.
6. MAINTENANCE AND INSPECTION
The maintenance and disassembly operations of the pump must be performed only
by authorized and specifically trained personnel.
6.1 USE PRECAUTIONS
Before performing any maintenance operation, please observe the following safety precau-
tions:
- Never execute maintenance operations with the pump running.
- Cut the power supply to the pump unit.
- Wear gloves, glasses, shoes and protective suits adequate to the characteristics of the liq-
uid being pumped.
- Wait until the pump is cooled.
- Never open the pump unit and/or the relief valve when the pump is pressurized.
- Close suction and discharge pipe valves, if any.
- Disconnect the pump from suction and discharge pipes, by paying attention to put a col-
lecting basin for the pipe liquid.
- Cut the power supply to the motor and disconnect the earth cable.
- Unscrew anchoring screws and remove the pump unit.
- Disconnect the pump from the motor.

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- Pay special attention to the effects of the magnetic pull force; in particular beware
of fingers (always use safety gloves). Be careful not to damage magnets by acci-
dental shocks. You are recommended to use tools in non-magnetic material.
- Place a collecting basin for the pump liquid.
- Perform the maintenance operation.
- Carry out the pump-motor coupling carefully.
- Secure the unit by anchoring screws.
- Connect the pump to suction and discharge pipes.
- Reconnect the power supply to the motor and the earth cable.
- Open suction and discharge pipe valves, if any.
- Reconnect the power supply to the pump unit.
6.2 WEARABLE MATERIALS
The normal wear parts, included as spares in the 2-year warranty are the following:
- bearing bushes;
- seal parts (mechanical seal, gaskets);
- gears;
- shafts.
6.3 SURVEILLANCE DURING OPERATION
The pump unit does not need the presence of an Operator during the work cycle. It is up to
the User to provide or not a periodic surveillance depending on the importance and serious-
ness of the operation. The relevant checks shall be aimed to detect abnormal noise, vibra-
tion, temperature levels and/or some dripping from the mechanical seals, variations of pres-
sure and/or flow rate, etc.
6.4 PREVENTIVE MAINTENANCE
It is always advisable, for a reliable and cost-effective operation, to adopt a policy of preven-
tive maintenance. The service time specified for wearable component parts in this manual
can be used as reference for the first period of operation. Later the user will be able to im-
prove the MTBM (Mean Time Between Maintenance) as a result of the acquired experience.
6.5 PUMP DISASSEMBLY AND REASSEMBLY
6.5.1 Tools
No special tools are requested, except for seal extractors.
6.5.2 Disassembly/reassembly procedure
Before disassembling the pump, it is necessary to perform the operations mentioned at point
4.6.1 "MAINTENANCE AND INSPECTION".
Refer to the drawings and nomenclature attached at the end of the manual.

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1) Single seal (see Figure 1)
a) Access to the mechanical seal
Remove the lantern from the engine, unscrew the fastening pin Fand disassemble the cou-
pling H. Disassemble the clamp Eand disconnect the pump from the lantern J; remove
the feather key Gfrom its housing.
Remove, by means of the proper pliers, the seeger rings ?housed in the front cover :, ex-
tract the ball bearing @and the gland ring >which houses the stationary ring of the me-
chanical seal <A. In this way, it is possible to check the wearing status of the seal contact
surfaces. During re-assembly do not pinch the O-ring =housed in the front of the pump
body.
b) Replacing static seal
To remove the static part of the seal <A from the seal cover >, it is necessary to carry out
the same operations as item a) and exert a pressure upon the external side of the seal. After
placing the seal cover on a plane and greasing the walls to make assembly easier, insert the
new static seal with the relevant O-ring; use a pad interposed with a soft bearing to exert the
force perpendicularly to the cover.
c) Replacing dynamic seal
To remove the dynamic part of the seal <it is advisable to use an iron wire bent at 90° at
one end to hook the first or the second coil of the seal spring <B. Exert a traction force par-
allel to the shaft K, by paying attention not to scratch this last. After greasing the shaft to
make assembly easier, insert the new mechanical seal by rotating the spring in the direction
opposite to that of the coil; use a pad interposed with soft bearing to press the seal up to
make the spring <B rest on the seeger ;provided on the shaft.
2) Magnet coupling (see Figure 2)
a) Access to the inner magnet
Place a container of suitable capacity under the inner magnet bell; unscrew the Allen screws
`and disassemble the ring ^, the bell aand the O-ring Y. Unscrew the fastening pin 46
and the screw band disassemble the inner magnet \. On reassembly, pay attention not to
pinch the sealing O-rings Yhoused in the flange Z. You are recommended to use tools
in non-magnetic material.
d) Replacing bearing bushes
Carry out the same operations as indicated in items a), b), c), e). To replace the supporting
bushes 4and 4A, break them with a chisel or similar, paying attention not to damage the
diameter of the bushing seats. Before inserting the new bushings, clean accurately the seat
with alcohol to remove all impurities and wipe them very well. Fit new bushes by spreading a
thin layer of glue of “LOCTITE 648” type over their outer diameters, by paying attention that
the cut bush and the integer bush match perfectly. First introduce the integer bush and then
the other, by letting glue dry for about 10 - 15 minutes. When the operation is over, set to ze-
ro the bush shims with the relevant housing covers. If a surfacing feed is not available, you
can choose a base plane abraded with fine emery cloth with P80 type grain for rough grind-
ing and 400 type grain for finishing. For assembly, follow the instructions at points e), c), b),
a).
e) Replacing gears and shafts
Carry out the same operations as indicated in items a), b), c).Remove the socket head
screws Bfastening the rear cover 1and remove it, considering that the operation might be
difficult because of the accuracy of shafts and dowel pins C.

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Draw a reference mark on the main body 9to avoid reversing base planes on reassembly
and remove it together with the 2 O-ring gaskets 7housed in it; the operation may become
difficult for the accuracy of shafts and dowel pins C. Remove the duct shaft 2, remove the
locking spring clip 5, remove the duct gear 6A from the shaft and extract the feather key
8; carry out the same operation on the conductor shaft, after disassembling the seeger ring
;in the front side.
On reassembly, reverse the procedure, by taking as reference the position of the rear cover,
the position of dowel pins and internal drain lines holes and do not pinch the O-rings 7.
Tighten the cover "cross" fastening screws Bby rotating simultaneously the motor shaft, to
avoid differentiated pressures on gears, which might increase frictions. With regard to tight-
ening torques, see paragraph 4.6.3. Then carry out operations indicated in items c), a).
f) Safety valve replacement
Unscrew the cap Oand remove the external sealing washer L. Move the nut and un-
screw completely the adjusting ring nut N, paying attention to the thrust exerted by the
spring A; disassemble the internal sealing washer L.
Remove the spring Awith the shutter assembled D.
Disassemble the valve seat Pand the sealing washer L.
During re-assembly check the correct coupling between the shutter Dand the seat Pand
replace all sealing washers L.

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BLANK PAGE

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7. FAULTS: CAUSES AND SOLUTIONS
Here below the most common causes of malfunctions in the operation of pumps are shortly
listed together with the possible solutions.
SOLUTION
Verify electrical connections and thermal protections Verify rating and type of (star - delta) motor connection Reduce the inverter start ramp Verify that shafts rotate freely Reverse electric motor connections Open valves Disassemble and clean the filter Drain pipes. Remove siphons. Tighten fittings and flanges Increase the pipe diameter. Re- move abrupt variations of section and direction Preheat the fluid. Decrease the speed of rotation. Stabilize the mains voltage Stabilize the electric circuit Increase the inertia of the hydraulic circuit Drain pipes. Remove siphons. Tighten fittings and flanges Increase the valve operating pres- sure Replace with free ball foot valve
CAUSE
The motor is not powered Incorrect supply voltage Excessive power consumption Mechanical lock of motor and/or pump shafts Direction of rotation reversed Valves on suction and/or discharge pipes closed Suction filter clogged Presence of air in the suction pipe High pressure losses in the suction line Fluid too viscous Overvoltage and/or overcurrent Feedback electric circuit too sensitive Feedback hydraulic circuit too sensitive Presence of air in pipes Intermittent opening of the by-pass valve Foot valve not working properly or of the type with plate and spring
ORIGIN
Electrical Electrical Electrical Mechanical Electrical Hydraulic Hydraulic Hydraulic Hydraulic Hydraulic Electrical Electrical Hydraulic Hydraulic Hydraulic Hydraulic
FAULT
The pump does not start The pump does not suck liquid at startup Pressure and/or flow rate pulses in the discharge line

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SOLUTION
Drain pipes. Remove siphons. Tighten fittings and flanges Decrease pressure losses in the suction line. Reduce the speed of rotation. Change fluid temperature Replace ball bearing and/or bushes Decrease pressure losses in pipes. Reduce fluid viscosity Decrease the speed of rotation or increase the fluid temperature Increase by-pass valve spring pre- load Decrease pressure losses in the suction line. Change fluid tempera- ture. Decrease speed of rotation. Increase by-pass valve spring pre- load Cool the fluid Grind rear cover Decrease the fluid temperature
CAUSE
Presence of air in pipes Cavitation Ball bearing and/or bush failure Pump saturation Excessive speed of rotation in relation to the fluid viscosity By-pass valve opening Cavitation By-pass valve opening Friction increase by thermal effect Gear shim adjustment to a given clear- ance gear Decrease in viscosity due to the tem- perature increase
ORIGIN
Hydraulic Hydraulic Mechanical Hydraulic Hydraulic Hydraulic Hydraulic Hydraulic Mechanical Mechanical Hydraulic
FAULT
The pump is noisy and vibrates The flow rate does not increase as the speed of rotation in- creases Progressive reduc- tion of the discharge flow rate and/or pressure, with con- stant speed of rota- tion