GemmeCotti HV User manual

Pag. 1di 26
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P PU UM MP PS S H HV V/ /H HV VL L
Vertical pumps
I
IN NS ST TA AL LL LA AT TI IO ON N, , O OP PE ER RA AT TI IO ON N A AN ND D
M
MA AI IN NT TE EN NA AN NC CE E M MA AN NU UA AL L
(
(S SA AF FE ET TY Y I IN NS ST TR RU UC CT TI IO ON NS S) )

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INDEX
1. INTRODUCTION.........................................................................................................................4
1.1 General..................................................................................................................................4
1.2 Purpose of the manual ...........................................................................................................4
1.3 Warning symbols for safety....................................................................................................4
1.4 Qualification and training of the personnel............................................................................4
1.5 Explosive atmosphere zones................................................................................................... 5
2. INSTALLATION......................................................................................................................5
Preliminary remarks....................................................................................................................5
2.1 Safety general warnings ........................................................................................................5
2.1.1 Introduction about danger ................................................................................................5
2.1.2 Indications of danger........................................................................................................ 5
2.2 Receipt and Inspection........................................................................................................... 6
2.3 Storage ..................................................................................................................................7
2.4 Installation.............................................................................................................................7
2.5 Hydraulic system....................................................................................................................7
2.6 Pipes connection.................................................................................................................... 7
2.7 Monitoring equipment............................................................................................................8
2.8 Motor connection................................................................................................................... 8
3. OPERATION ............................................................................................................................9
3.1 Use and safety........................................................................................................................9
3.2 Dry-running......................................................................................................................... 10
3.3 Temperature......................................................................................................................... 10
3.4 Before starting..................................................................................................................... 10
3.5 Starting................................................................................................................................ 11
3.6 Optimum conditions for use.................................................................................................. 11
3.7 Shut down ............................................................................................................................ 11
3.8 Long pump inactivity............................................................................................................ 12
3.9 Noise level ........................................................................................................................... 12
4. MAINTENANCE.................................................................................................................... 12
4.1 General dispositions ............................................................................................................ 12

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4.2 Inspections........................................................................................................................... 13
4.3 Procedure before disassembly.............................................................................................. 13
4.4 Disassembly......................................................................................................................... 13
4.4.1 Main parts...................................................................................................................... 13
4.4.2 O-ring and bearing replacement .................................................................................... 15
4.5 Assembly.............................................................................................................................. 16
4.6 Motor replacement............................................................................................................... 18
4.7 Tightening torque................................................................................................................. 18
5. PROBLEM SOLUTIONS....................................................................................................... 19
6. SPARE PARTS ....................................................................................................................... 20
6.1 How to order spare parts ..................................................................................................... 20
7. DATA....................................................................................................................................... 20
7.1 Performance curves ............................................................................................................. 20
7.2 Dimensions.......................................................................................................................... 21
7.3 Technical data and limits........................................................................................................................23
8. WARRANTY AND REPAIR ................................................................................................. 23
8.1 Warranty.............................................................................................................................. 23
8.2 Returned parts and repair.................................................................................................... 24
8.3 Decontamination Declaration (facsimile)............................................................................. 25
8.4 CE Certificate for pumps series HVL PP/PVDF................................................................... 26

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MANUAL HV-HVL PUMPS REV 1
GemmeCotti s.r.l. via Alessandro Volta, 85/A - 20816 Ceriano Laghetto (MB) –ITALY EU - tel. [phone] –
fax [phone] - [e-mail] –CF.P.IVA –VAT IT 02057740124
1 1. . I IN NT TR RO OD DU UC CT TI IO ON N
1.1 General
This manual refers to vertical centrifugal pumps series HVL. Pumps HVL are made of
thermoplastic materials (Polypropylene or PVDF) and can be of different sizes. Dimensions
and capacities available are described in paragraph 7.0.
1.2 Purpose of the manual
The main purpose of this manual is to assure that the activities of installation, operation and
maintenance of the pumps are executed in a correct and safe way by all the personnel in
charge of these operations. This document offers also indications useful for the customer to
solve the problems, order spare parts and contact GemmeCotti repair service.
1.3 Warning symbols for safety
This symbol indicates a possible danger caused by the presence of
electrical fields, contacts or wires with electric current.
All the symbols with the exclamation mark indicate an important situation
that needs the attention of the personnel. In particular, these are indications
useful for the correct functioning and prevention of possible damage to the
equipment.
This symbol signals a danger or a situation that requires the maximum
attention of the personnel. It's important to respect the instructions stated at
the margin of this symbol and proceed very carefully. It's necessary to
inform all the personnel and/or users that the rules indicated prevent
injuries.
1.4 Qualification and training of the personnel
Those in charge of the installation, operation and maintenance of the pumps have to be
qualified to carry out the actions indicated in this manual. GemmeCotti is not responsible for
the inadequate qualification and training of the customer's staff or for the lack of information
of the staff regarding the contents of this manual. It's compulsory to always show this
manual to the workers in charge of the installation, operation and maintenance of the pump.
Keep this manual in a safe place for future consultations.

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MANUAL HV-HVL PUMPS REV 1
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fax [phone] - [e-mail] –CF.P.IVA –VAT IT 02057740124
1.5 Explosive Atmosphere Zones
The pumps described in this manual CANNOT be used in explosive atmospheres. These
uses require special pumps that GemmeCotti manufactures with particular materials and
precautions. Customers who want to use special pumps in these kind of zones have to
contact the GemmeCotti technical office for the correct choice of the product.
WE REMIND YOU THAT THE CLASSIFICATION OF THE ZONE (REF. ATEX
94/9/CE- 2006/42 DIRECTIVE) FOR POTENTIALLY EXPLOSIVE ATMOSHPERE
ZONES HAVE TO BE DONE BY THE CUSTOMER AND COMMUNICATED TO
GEMMECOTTI FOR THE RIGHT CHOICE OF THE KIND OF PUMP SUITABLE
TO WORK IN THESE ZONES.
The pumps, manufactured by GemmeCotti, for these kind of applications belong to the series
EM-C or EM-T or EM-P.
Furthermore, the customer is responsible of the correct installation of the pump in
accordance with the requirements stated in the Directive.
2
2. . I IN NS ST TA AL LL LA AT TI IO ON N
Preliminary remarks
All the references to the pumps have to be considered applicable also to systems that use these pumps
unless it's specified otherwise.
2.1 Safety general warnings1
2.1.1 Introduction about danger
ATTENTION: the non-observance of the indications stated in this manual or the
inappropriate use of the equipment by unqualified or unauthorized staff, can cause
serious personal injuries or death and damages to products and apparatus!
The technical assistance office is at the complete disposal; in case of doubts or problems you
can contact us by phone (Number +39 02 964.60.406) or write an email to
[e-mail]. It's strongly recommended that you keep GemmeCotti written
answer.
2.1.2 Indications of danger
For the safety of those in charge of the installation of the pump it's necessary to use safety
clothing and individual safety devices approved by the current provisions of the law (e.g.
Safety glass, gloves and safety insulating-shoes)
These pumps have been designed and manufactured to be used in specific conditions and
within defined limits. The use outside these specifications has to be agreed and approved by
GemmeCotti technical service. It must be considered also that, if the pumps are used
outside their technical specifications, the CE Certifications and the warranty are no
1If these warnings are not observed the Certification and the Warranty of the pump can be invalidated

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MANUAL HV-HVL PUMPS REV 1
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longer valid. Furthermore, if the pump is used outside the technical specifications
communicated to us at the moment of the quotation and confirmed in our order
confirmation, the customer becomes responsible for the issue of a new CE Certification.
The pump has to be used only for the applications specified in the order for which
GemmeCotti has selected the model, the materials of construction and has tested the pump to
respect the specifications. For other uses different from those stated in the order, the
customer has to send always a written request to GemmeCotti technical office, which on its
part will reply in a written form.
There will not be any warranty for repairs or alterations on the product done by the users or
third parties not specifically authorized by GemmeCotti.
Always shut down the pump before touching or proceeding with any intervention on it or on
the circuit of installation. The pump must be empty of pumped liquid and it must be
completely decontaminated and successfully rinsed with water before any manual operations
or disassembling.
Make sure that the electrical system to which the pump will be connected has the adequate
power and has the correct protection devices (e.g. Grounding, Life safe).
Always switch off the electrical supply before working on the pump for maintenance or part
substitution.
Always keep an extinguisher next to the pump installed.
Always pay maximum attention in the execution of maintenance activities on pumps and on
the connected circuits when they are used with dangerous liquids.
The use of an electric starter is recommended. A simple switch can be insufficient to start
and stop the electric motor connected to the main electric system.
An appropriate starter:
- can prevent accidental starting after a failed attempt to start:
- is a safe switch, protected against water:
- protects the electric motor against overloads due to a short circuit (a fuse protects only the
wires);
- resists against starting in overload on the motor, preventing dangerous electric arc and early
wear of the electrical contacts.
2.2 Receipt and Inspection
Even if GemmeCotti takes all the necessary precautions during the packaging, we suggest
that you carefully check the received material. Check for any missing parts caused by the
courier and/or by GemmeCotti.
Check the data on the label of the received pump and compare it with those relative to your
purchase order.
If the pump has been supplied with the motor, remove the protective shield from the fan of
the motor and try to rotate the motor shaft by hand. If you feel a strong resistance to rotation
or if you hear anomalous noises call your reliable reseller or call the GemmeCotti assistance
service directly. Reassemble the protective fan shield before starting the pump.

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2.3 Storage
If the pump is kept in the warehouse make sure that it's placed in a dry and protected
position; always use the original package or an equivalent protection. If the pump has to
remain stored for a long period and/or in particularly damp places the use of hygroscopic
substance (silica gel) is recommended to prevent damages.
Don't remove the protections of the flanges until the installation and close, if they are not
closed already, the discharge and suction pump connections to prevent the intrusion of
foreign bodies.
Be informed that a long period of storage of the pumps can provoke:
-deterioration of the isolation of the motor due to absorption of dampness
-deterioration of the gaskets
2.4 Installation
GemmeCotti s.r.l. is not responsible for injury to people or damage to things caused by the
wrong installation of the pump or installation executed by non-qualified personnel.
Install the pump in a position that guarantees a simple use.
The unit motor/pump has to be fixed on a rigid structure that will enable the support of the
entire structure. Make sure that the pump is fixed on a plane surface, in this case use shims
under the base-plates of the motor. If necessary use “bumpers”to reduce vibrations towards
the fixing surface.
ATTENTION: the pump has to be installed perfectly vertical and the plate must be fixed to
a rigid appropriate frame over the pump dip.
2.5 Hydraulic system
The pump is generally part of a hydraulic system that can include a various number of
components such as, valves, fittings, filters, expansion joints, instruments, etc. The way the
piping is arranged and the position of the components has a great influence on the operation
and on the life of the pump.
2.6 Pipes Connection 2
Locate the pump in the pit. The liquid level should not go under the hole placed in the low
part of the column.
The liquid lever should not go over the hole placed on the top of the column, near the
2If these warnings are not observed the Certification and the Warranty of the pump can be invalidated

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MANUAL HV-HVL PUMPS REV 1
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bracket.
The piping should be properly supported and kept in line independently from the
pump, until its connections, so that the piping doesn't exert loads on the pump
discharge.
The size of the discharge pipe has to be at least as large as the inlet connection of the pump.
Diameter restriction of the suction nozzle is responsible and cause of the cavitation of the
pump, creating a loss in the performance of the pump and a rapid wear. It's advisable always
to use (if in case) a suction strainer with suitable diameter. If required, GemmeCotti can
supply a correct and suitable strainer.
The suction dip has to be clean and/or a strainer has to be fit to protect the impeller from
damage due to impurities, or other foreign particles, especially when starting the plant for the
first time.
Don't use metallic piping with plastic pumps.
Don't use tools to connect piping to plastic pumps. Make sure that the connections
are properly tightened.
The installation of a proper pressure gauge on the discharge pipe is recommended. The
installation of gauges allows an easy control of the correct functioning of the pump in
relation with the required working point. In case of cavitation or other dysfunctions, the
gauges will show evident pressure fluctuations.
2.7 Monitoring equipment
According to the importance of the pumping system, it could be useful to maintain a strict
control of the performances and conditions of the process. The use of instruments to monitor
the pressure of the discharge circuit is recommended.
Even the monitoring of the electric power absorbed by the motor is possible using a
wattmeter.
If the temperature of the pumped liquid represents a critical element install in the system a
thermometer, preferably on pump dip.
These control instruments can advise of abnormal operating conditions of pumps.
2.8 Motor connection
Check that the tension and frequency printed on the label of the motor correspond to those of
the electric system to be used.
Don't connect the electric motor directly to the main system but protect the dedicated system
with a suitable main switch with adequate safety protections against overloads.
The electric connections have to be always carried out by an expert qualified electrician.
The motors have to be supplied with three-phase tensions or if required by the customer,
with single phase tension. The type of connection of the three-phase motors can be Star (U)

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MANUAL HV-HVL PUMPS REV 1
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fax [phone] - [e-mail] –CF.P.IVA –VAT IT 02057740124
ATTENTION:
Dangerous or hazardous actions can cause serious injuries or death to people or serious damage to
materials and so it's important to assure the respect of all the warnings relative to the safety and the
correct use written in this manual.
or Delta (D) according with the power supply 380 or 220 VAC (see picture 1).
picture 1
Make sure that the sense of rotation of the motor is that specified on the pump bracket, on
the pump drawings and eventually indicated by a sticker arrow on the motor fan; to change
the sense of rotation it's sufficient to change two of the three entering line (E.g . L1 with L2)
in three-phase motors.
Read the following instructions to change the sense of rotation:
-wear individual homologated protection devices (e.g. Gloves, glasses)
-make sure that the operating conditions are analogous to the specifications of the pump
(see paragraph 7)
-install the pump in the hydraulic system
-open the the discharge valve completely;
-fill the pump with the liquid. It' s recommended to perform this test with an inert liquid
like water
-do not run the pump dry
-start the motor only for one or two seconds to check that the sense of rotation is in the
same direction of the arrow on the pump head.
NOTE: a pump turning backwards (wrong rotation sense) will pump but at a greatly reduced
capacity and pressure
3. OPERATION
3.1 Use and safety
Verify always that the pumped liquid is compatible with the materials of construction of the
pump. For any clarification please contact GemmeCotti technical office.
In case of use for pumping aggressive, toxic liquids or liquids dangerous for the health of the
personnel, it's necessary to install on the pump an adequate protection for the containment,
the collection and the warning of any dangerous product in case of leakage: e.g. DANGER
OF POLLUTION, CONTAMINATION, INJURIES AND/OR DEATH
Do not reduce the suction. Reduction of the suction is responsible of the cavitation of the
pump, which causes a loss of efficiency and a rapid wear. Reduction of the discharge are not
advisable, if required, reduction of the capacity can be obtained by means of a valve installed
on the discharge pipe.

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MANUAL HV-HVL PUMPS REV 1
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Do not loosen the connection of the pump while it's under pressure.
Do not start and/or use the pump if there are signs of leak in the system.
The working temperatures have to respect the characteristics of the construction materials of
the pump:
·60 °C polypropylene execution (PP)
·80° C PVDF execution
DO NOT ALLOW THE PUMP TO RUN DRY (note: the pump design doesn't allow the
dry-running functioning because it will damage irrevocably the inner parts of the pump). A
system with level switches that can stop the pump is strongly recommended.
An accidental failure can generate sprinklings up to considerable distances.
In case of vibrations or anomalous noises, stop the pump immediately .
Do not pump inflamed liquids.
Do not touch the pump while operating.
Before touching the motor or the bracket switch off the electric current.
3.2 Dry-running
Fill the pump dip with water or with the liquid to be pumped before starting the unit. This
will protect the bearings, sleeve and the shaft of the pump against dry running. DO NOT
ALLOW THE PUMP TO RUN DRY because this can cause serious damage to the internal
parts of the pump due to the lack of the necessary lubrication.
3.3 Temperature
Increasing the temperature of the pumped liquid can damage the pump and/or the
piping/fittings and there can be a situation of serious danger for the people in the
nearby.
Avoid sudden changes of the temperature and do not exceed the temperature specified in
your order. See the value of temperatures of the construction materials of the pumps in the
paragraph 3.1.
3.4 Before starting
Make sure that the pump is installed in accordance with the instructions supplied in the
previous section 2.
When the pumping station is new, it's necessary to fill the system with water to control that
there are no leaks. WHEN THE PUMP IS INSTALLED CHECK THE LIQUID
LEVEL IN THE PUMP DIP, THIS MEANS THAT THE PUMP CASING HAS TO BE

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MANUAL HV-HVL PUMPS REV 1
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KEPT SUMERGED IN THE LIQUID BEFORE STARTING THE PUMP.
ATTENTION: some liquids react with water. VERIFY IF THE LIQUID TO BE
PUMPED REACTS WITH WATER. IN THIS CASE THE SYSTEM HAS TO BE
COMPLETELY EMPTIED AND DRIED.
3.5 Starting
Start the electric motor and gradually open the discharge pipe until you reach the required
flow.
The pump can't operate more than two or three minutes with the discharge closed. A longer
period can cause serious damage to the pump.
If the pressure shown on the pressure gauge on the discharge piping does not increase, stop
the pump immediately and release the pressure carefully.
Repeat the operation of installation of the pump as in paragraph 2.
If during the starting procedure there are changes of flow-rate, of density, temperature or
viscosity of the liquid, stop the pump and contact GemmeCotti technical service.
3.6 Optimum conditions for use
Operating continuously at the maximum performances (maximum capacity/head) there can
be an early wear of the pump. As a general rule, we recommend using the pump at half of its
maximum capacity (see the paragraph relative to the technical data)
The capacity and the head of the pump refer to water pumping at room temperature. If it
pumps high temperature liquids or other viscosities and densities, the performances have to
be proportionately decreased. Pumps of series HVL work well with liquids having a
viscosity up to 100 CPS3and specific gravity up to 1.93. HOWEVER BOTH THE
VISCOSITY AND THE SPECIFIC GRAVITY HAVE TO BE COMMUNICATED AT
THE MOMENT OF QUOTATION. The electric motor is selected for the viscosity and the
specific gravity communicated. In the case of higher values, the power of the motor could
be insufficient.
3.7 Shut down
Normally the pump should be shut down only after closing the discharge valve.
In some cases the pump can be used to empty tanks, in these situations the liquid can stop
flowing in the pump while this is still working. In these cases a pump operating without
liquids (that means dry-running) can be dangerously damaged if it's not stopped
immediately. For such applications the use of automatic equipment or the constant presence
of a person who can shut down the pump is recommended.
3The values indicated are merely indicative and can vary in the series of pumps mod. HVL

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3.8 Long pump inactivity
If the pump has to remain inactive for a long period, before stopping it, it's recommended to
let water flow in the system for several minutes so that you avoid any risk of internal
deposits or sediments or precipitations of solid parts. Drain the liquid in the pump. An
eventual freezing of the liquid inside the pump can cause damage. Always verify if the
pumped liquid reacts with water. In this case contact GemmeCotti to find an alternative
solution.
If the pump is temporary removed from the system and kept in stock, it's necessary to follow
the instructions of paragraph 2.3 “Storage”.
3.9 Noise level
In some circumstances, for example when the pump works with high pressure and low
capacity the noise increases and can be disturbing for the personnel working in the
proximity. In this case it's possible to intervene with:
·earplugs;
·protective homologated caps against noises for the personnel in the proximity;
·soundproofing canopy for the pump. In these cases make sure that the motor
ventilation is guaranteed.
4. MAINTENANCE
4.1 General dispositions
During the warranty period disassembly activities of the pump are allowed only for
GemmeCotti personnel or personnel authorized by GemmeCotti. All the operations
described in the paragraphs below have to be done exclusively by qualified staff and
following step by step all the warnings written in this manual.
Clean the external surface of the pumps using only antistatic equipment.
Every operation executed on the apparatus has to be done after the disconnection of electric
supply.
Use exclusively a goods lift to move pumps with weight higher than 16 kg. During the
movements of the machine or parts of the machine avoid collisions or falls which can
damage the apparatus.
The bearings (pos. 15) have to be periodically greased through the lubricated nipple (pos. 11)
on the bracket.
Before disassembling the parts of the pump, make sure that the dangerous internal liquids
have been removed /washed. THE PUMP HAS TO BE DRAINED AND
DECONTAMINATED.
Pay attention that some internal liquids can have dangerous reactions in contact with water.
During the operations of unloading of dangerous liquids make sure that situations of danger
for people or environment don't occur.

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MANUAL HV-HVL PUMPS REV 1
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ATTENTION:
If the pump has pumped hot liquids, make sure that it's been cooled before the disassembly
procedure. It's possible that the pump has pumped toxic and/or dangerous liquids: so it's
necessary to wear protection for the skin and the eyes.
4.2 Inspections
In general vertical pumps do not need a “routine”maintenance and most of all they don't
require frequent dismantling.
However periodical inspections are advisable to verify the state of wear of the impeller, the
shaft and the bearings and if the general conditions of the internal parts of the pump are
good.
The time between the inspections is strongly dependent on the operation conditions of the
pump: the characteristics of the liquid, the temperature, the materials used and obviously the
period of operation.
If a problem occurred or the pump needs a complete inspection see section “Problem
solutions”and “Pump disassembly”.
4.3 Procedure before disassembly
ATTENTION:
Make sure that the pump has been carefully decontaminated and cleaned. Wash and
neutralize completely the dangerous liquids inside the pump. The liquid has to be collected
and eliminated according to the existing environmental laws. After disconnecting the
discharge pipe close the extremities.
4.4 Disassembly
NOTE: the photos used to show the operations of disassembly refer to a particular pump
model of the series HVL and consequently the pump supplied to you can be slightly different
from what is shown.
4.4.1 Main parts
The drawing below shows a section with all the main parts of a pump series HVL in
thermoplastic material (in particular models 110-140).

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MANUAL HV-HVL PUMPS REV 1
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fax [phone] - [e-mail] –CF.P.IVA –VAT IT 02057740124
Photo N. 1 shows the main parts of a pump series HVL in thermoplastic material (excluding
the motor)
Foto N. 1 Foto N. 2
4.4.2 O-RING AND BEARING REPLACEMENT
Operations:
1. Remove the screws securing the pump head to the column (Photo N.3-4) and separate it
together with the discharge pipe from the rest of the pump.
Photo N. 3 Photo N. 4
2-Check the wear of the o-ring pos. 37 and if necessary replace it (photo 5). Unscrew
the impeller nut using appropriate key and bar as in photo 6 and 7 and replace the
o.ring pos. 41. Note that the impeller nut is left-handed thread, rotate clockwise to
unscrew it.
photo N. 5 photo N. 6 photo N. 7 photo N.8

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ATTENTION:
Clean accurately every component before assembly, make sure that the parts are not dirty,
and don't have metallic particles etc
3-After removing the impeller and the o.ring (photo 7 and 8) check the wear of the o.ring
pos. 26 and the static bushing in PTFE pos. 27, the rotating bushing in ceramic pos. 35 and
the key pos. 22 (photo 9-10).
Photo 7 photo 8 photo 9 photo 10
4.5 Assembly
The sequence (in reverse) of operations of assembly is the same as that of disassembly.
However it's necessary to consider the following warnings:
· make sure that when closing the pump, the o-ring is perfectly in seat and is not
pinched;
· use dynamometric wrench for the correct strength to tighten the bolts in accordance
with the chart of the following section 4.7.
· after assembling the pump on the motor flange, remove temporarily the protective
shield on the fan at the back of the motor and rotate it by hand to check the free rotation
of the unite. In case of excessive friction or anomalous noises, disassemble the group
(instructions paragraph 4.4) and find out the cause of the problem. Never use the pump
without proceeding with this test. Reassemble the fan protective shield before starting
the pump, do not start the pump if the fan protective shield is not installed.
1. Place the column pos 33 complete with flange and plate as shown in photo 2 with the small hole
above.
N. 2

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GemmeCotti s.r.l. via Alessandro Volta, 85/A - 20816 Ceriano Laghetto (MB) –ITALY EU - tel. [phone] –
fax [phone] - [e-mail] –CF.P.IVA –VAT IT 02057740124
·Mount the cover on the column. (photo 3 to 5) and fix it.
N. 3 N. 4 N. 5
·Screw the elbow pos 43 to the pump head pos 42 and to the discharge pipe pos 44. Insert the
discharge pipe into the hole in the plate (photo 6) and place the pump head on the cover. Rotate the
column until the pipe is perpendicular to the plate and parallel to the column. When you find the
correct position check if everything is ok and remove the pump head and the pipe.
N. 6 N. 7 N. 8
·Place the o-ring pos 26, the static bushing in PTFEC pos 27, the rotating bushing in ceramic (pos 35)
and the key pos 22 on the shaft (photo 9-11.) Prepare the impeller placing the o-ring in the rear
side, then place it on the shaft in the correct position guided by the key. (Photo 12-13).
N9 N. 10 N. 11 N. 12 N. 13
9. Place the o.ring pos 41 on the impeller and block everything with the nut pos 40. Then place o-ring
pos 37 on the cover (photo 17)

18 of 26
MANUAL HV-HVL PUMPS REV 1
GemmeCotti s.r.l. via Alessandro Volta, 85/A - 20816 Ceriano Laghetto (MB) –ITALY EU - tel. [phone] –
fax [phone] - [e-mail] –CF.P.IVA –VAT IT 02057740124
N. 14 N. 15 N. 16 N. 17
·Position the pump head with the discharge pipe placed in the hole in the plate as described in point 4.
Block the pump head with 8 screws M12 x 50 mm (pos 50). In order to fix the pump head follow the
following instructions:
1- Tight 2 bolts in metal one on each side of the pump head (opposite to one another) and tight
them
2- Position all the other remaining bolts in plastic and tight them gently without applying too much
strength
3- Remove the metallic bolts and replace them with the remaining 2 bolts in plastic following the
same procedure to tight them.
4- Check with the dynamometric wrench the correct tightening of the bolts.
·Fix the flow pipe with its flange pos 49 in which is located the suitable o-ring 59,69 x 5,33 (pos 52).
N. 18 N. 19 N. 20
4.6 Motor replacement
Proceed as indicated in the previous paragraph 4.4.2. Make sure that the characteristics of the
motor are equal to those of the replaced motor. The manufacturer of the new motor can be
different from that of the motor already mounted.
4.7 Tightening torque
The recommended tightening torque are written in the following chart:
chart 1
Bracket on the
motor
H
V/HVL
110
-
120
M10 X 40mm
–
10 Nm
HV/HVL
130
-
140
M10 X 40mm
–
10 Nm
HV/HVL
150
-
155
M10 X 60mm
–
15 Nm
HV/HVL
160
M10 X 60mm
–
15 Nm
HV/HVL
170
M10
X 60mm
–
15 Nm

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MANUAL HV-HVL PUMPS REV 1
GemmeCotti s.r.l. via Alessandro Volta, 85/A - 20816 Ceriano Laghetto (MB) –ITALY EU - tel. [phone] –
fax [phone] - [e-mail] –CF.P.IVA –VAT IT 02057740124
5. PROBLEM SOLUTIONS
1
M
o
t
o
r
/
o
v
e
r
l
o
a
d
2
I
n
s
u
f
f
i
c
i
e
n
t
/
s
p
e
e
d
/
o
f
/
t
h
e
/
f
l
o
w
/
o
r
/
p
r
e
s
s
u
r
e
3
I
n
s
u
f
f
i
c
i
e
n
t
/
p
r
e
s
s
u
r
e
/
f
r
o
m
/
t
h
e
/
d
i
s
c
h
a
r
g
e
/
p
i
p
e
4
I
r
r
e
g
u
l
a
r
/
d
e
l
i
v
e
r
y
/
p
r
e
s
s
u
r
e
/
f
l
o
w
5
N
o
i
s
e
s
/
a
n
d
/
v
i
b
r
a
t
i
o
n
s
6
B
l
o
c
k
e
d
/
p
u
m
p
7
P
u
m
p
/
o
v
e
r
h
e
a
t
i
n
g
8
A
n
o
m
a
l
o
u
s
/
w
e
a
r
9
L
e
a
k
/
i
n
/
t
h
e
/
p
u
m
p
Possible cause
Solution
· · Wrong direction of rotation of the
motor Invert the direction of rotation
· · · · Insufficient suction head (NPSH) Increase NPSH available:
·Raise the suction head (positive head)
·Lower the pump
· Pump clogged Clean the pump
· · · · Cavitation Increase the NPSH available
· · · · The pump sucks air The level of the liquid in the pump dip is too low
· · · The suction pipe is blocked Clean the pump dip
· · Discharge pressure too high Reduce the pressure increasing the diameter of pipes
and/or reduce the number of valves or bends
· · · Flow rate too high Reduce the flow:
·partially close the discharge valve
·reduce the rotation speed
· · · · · Liquid temperature too high Cool the liquid
· Wrong material of the o-ring for the
liquid Mount o-ring s of different material (contact us)
· · · · The impeller seizes up
·
Reduce the temperature

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MANUAL HV-HVL PUMPS REV 1
GemmeCotti s.r.l. via Alessandro Volta, 85/A - 20816 Ceriano Laghetto (MB) –ITALY EU - tel. [phone] –
fax [phone] - [e-mail] –CF.P.IVA –VAT IT 02057740124
·
Adjust the distance between the impeller, the
rear casing and the pump head
· · · · Foreign objects in the liquid Use a filter on the suction side
· Shut off valve closed on suction side Check and open the valve
· Discharge pressure too low Increase the suction pressure:
Install an impeller with bigger diameter (contact
GemmeCotti)
1 2 3 4 5 6 7 8 9
6. SPARE PARTS
6.1 How to order spare parts
A complete kit of spare parts for these kinds of pumps is available. Please contact
GemmeCotti or our distributors. To have the spare parts it's necessary to communicate the
model of the pump, the size, the material, the serial number, the year of construction and
the number relative to the spare part required. All the references are written directly on the
pump label and on the section drawings of the pump. If you don't have the necessary
drawings please contact the GemmeCotti sales office (tel. [phone]).
7. DATA
7.1 Performance curves