North Ridge Pumps NOVA ROTORS MN Series User manual

Product Specification Sheet
X-Cel House, Chrysalis Way, Langley Bridge, Eastwood, Nottinghamshire NG16 3RY
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FUNCTIONING AND
MAINTENANCE MANUAL
PROGRESSING CAVITY PUMPS

Pag.1 (Funct. and Maint.Manual n.03 – Fourth edition) OMI.EN-PCP001 R01
GENERAL
1.1 Introduction
This manual includes the instructions concerning the use and maintenance of
progressing cavity pumps made by NOVA ROTORS™ S.r.l..
The information included in the manual apply to the user, who must read and fully
understand it before using the pumps.
This instruction manual must always be available to the user for reference.
In case the manual is lost or damaged, you should require a new one to the pump
manufacturer.
Warning – The manufacturer is not held accountable for any improper use of the
pump should the manual be read in part or not read at all.
NOVA ROTORS™ S.r.l. is entitled to alter the specifications included in this manual or
the features of every pump. Some pictures in this manual may show parts that might be
slightly different from the ones assembled on the pump.
The manual is an integral part of each pump; therefore, it must be kept and equip the
pump also in the event that the pump may be made available to a different user.
1.2 Information about CE marking
As well as the CE mark, the details shown on the CE marking plate attached on each
pump include the following:
Manufacturer: NOVA ROTORS™ S.r.l.
Address: Via Carlo Cattaneo, 19/25
Town/City: 36040 Sossano (VI)
Machine: Progressing cavity pump
Model:
Manufactured in 2010
1.3 Compliance of pump with CE
Each progressing cavity pump is provided with a CE-compliance certificate issued by
NOVA ROTORS™ S.r.l.
The pump was made to comply with the basic safety requirements set out in these
applicable directives:
Directive on machinery: 2006/42/CE
Directive on low tension: 2006/95/CE
Directive on electro-magnetic compatibility.

OMI.EN-PCP001 R01 (Funct. and Maint.Manual n.03 – Fourth edition) Pag.2
In addition, pumps were designed and made in accordance with these standards:
UNI EN 809: 2009 – Pumps and liquid pumping units – General safety requirements.
UNI EN ISO 12100-1: 2005 – Machine safety. Basic principles, general design
principles. Part 1: Basic terminology, methodology.
UNI EN ISO 12100-2: 2005 – Machine safety. Basic principles, general design
principles. Part 2: technical principles.
CEI EN 60204-1: 2005 – Machine safety. Electric wiring. General rules.
1.4 Fields of application
Progressing cavity pumps are used to pump fluid as requested in the order concerned.
Any pump must not be used for fluid whose chemical and physical properties differ from
the ones set out in the order.
The max. pressure required must be lower than the max. pressure a pump can reach,
adequately reduced to take into account any leakage from delivery piping.
Unless otherwise stated, the pump must not be used in places where potentially-
explosive atmospheres may occur.
1.5 Noise
The average noise level A emitted by the pump must not be higher than 80dB(A).
1.6 Safety warning
1.6.1 Overpressure
The progressing cavity pump must be installed within a plant. The delivery pressure of
these pumps is only limited by the power of machines.
DANGER!
In case delivery of pump is intercepted, pressure rises until piping breaks or the pump is
damaged, which may cause leakage of fluid under pressure.
The plant must therefore be equipped with proper safety devices such as manostats
and fracture disks with return piping as shown in § 4.6.

Pag.3 (Funct. and Maint.Manual n.03 – Fourth edition) OMI.EN-PCP001 R01
1.6.2 Wiring
The wiring of machines equipped with electric motor must be made by the user in
accordance with the instructions set out in standard CEI EN 60204-1:2005.
Take care in:
•the choice of conductor section, which must be able to bear power at start-up with
locked rotor;
•connecting the conducting parts of pump to the earthing;
•connecting phases so as to perform the direction of rotation shown on the pump.
Little leakage of pumped fluid is expected for proper pump functioning.
DANGER!
All electric components installed close to the pump must be protected with casings
ranked IP 66 or higher.
1.6.3 Mobile parts of pump
The rotor of the progressing cavity pump is connected to the driving unit through a joint.
No removal of casings from mobile parts
The pump must not be started before placing and fixing the casing of driving unit.
1.6.4 Leakage of hazardous fluid
Should the pump be used with hazardous liquid such as poisonous, corrosive fluid, etc.,
fluid which may leak from seals must be collected and disposed without causing danger to
people or the environment.
1.6.5 Handling
Some pumps may reach considerable sizes and weights that they cannot be handled by
one single operator manually.
DANGER!
Before handling the pump, read the instructions in sect. 5 of this manual very carefully.

OMI.EN-PCP001 R01 (Funct. and Maint.Manual n.03 – Fourth edition) Pag.4
1.6.6 Pump maintenance
Pump maintenance work must be done when the pump is at a standstill.
Before removing the casings of mobile parts, make sure that the motor cannot be
started again before restoring safety conditions.
The pump must not be under pressure and must be cooled.
Pumps or units which feed substances affecting people's health must be
decontaminated.
Should a pump be disassembled to pump any hazardous fluid, the maintenance
operator must wear all DPI prescribed for handling such a substance.
Shortly after finishing maintenance work, all safety and protection devices must be
applied and set to work again.
Setting the pump to function again after maintenance work must be carried out following
the instructions set out in sect. 7.
1.6.7 Non-compliance with the instructions included in this manual
If the instructions included in this manual are not complied with, this may affect people's
health, the environment and the machine.
Such non-compliance may result in:
•inability to perform any key functions of the pump and/or plant;
•damage to the pump and/or plant;
•electric, mechanical and chemical dangers for people;
•danger for the environment due to leakage of hazardous substances.
1.7 Start-up, operation and maintenance
The plant in which the progressing cavity pump will be applied is not an integrating part
of the supply; therefore, the user must choose the pump which may best fit his needs, as
well as all the accessories needed to ensure the plant safety.
1.8 Safety warning for maintenance, inspection and assembly
The user must make sure that any maintenance, inspection and assembly of
progressing cavity pumps should be carried out by expert technicians. Before starting
work, the staff must have read this manual very carefully.
1.9 Alteration and discretionary production of spare parts
Any alteration or modification of the pump, within the extent of extraordinary maintenance,
are allowed subject to the manufacturer's agreement.
As for ordinary maintenance, original spare parts or any parts deemed to be suitable by
NOVA ROTORS™ S.r.l. must be used.
The use of non-original spare parts leads to the earlier termination of warranty.

Pag.5 (Funct. and Maint.Manual n.03 – Fourth edition) OMI.EN-PCP001 R01
2 PUMP FUNCTIONING
A progressing cavity pump is a rotating volumetric pump. The main parts of the system are
a rotary part called ROTOR (see Abelow) and a fixed part called STATOR (see B).
The rotor is a round thread screw with a very large pitch, a deep thread and a small core
diameter. The stator is double-threaded and has a pitch which is double compared to the
rotor, so that between the stator and the rotor there are delivery chambers. These move
continuously from the inlet side towards the outlet when the rotor is spinning inside the
stator.
In progressing cavity pumps the axis of rotation of the rotor A does not coincide with the
axis of rotation of the motor. The rotor is driven by a double-joint shaft. This shaft absorbs
eccentric motions and shifts axial stresses towards the motor shaft.
A B
The fluid coming from the stator/rotor group is conveyed to the central body, and then
ejected through the outlet.
3 BRIEF DESCRIPTION OF THE PRODUCT
3.1 Main technological features of progressing cavity pumps
* Steady capacity, proportional to motor speed.
* Self-priming, with a min. suction of 4 mt (NPSH), depending on the number of stages
and rpm of the pump.
01 Outlet
02 Rotor
03 Stator
04 Connecting Rod
05 Hollow shaft
06 Pump body
07 Shaft seal
08 Bearing housing
09 Close coupled
10 Male shaft
11 Shaft joints

OMI.EN-PCP001 R01 (Funct. and Maint.Manual n.03 – Fourth edition) Pag.6
* Pumping of non-homogeneus products, containing gas and abrasive or solid and
fibrous material in the fluid.
* Pumping of very high viscous liquids.
* Dosage of liquids.
* No inlet or delivery valves.
* Centrifugation-free pumping with low tension stress in the pumped material.
* High pumping pressure (6 BAR for each stage). Pumps may have one up to four
stages, according to the pressure required:
3.2 Classification
Progressing cavity pumps are divided into two main categories, according to the coupling
between pump and motor:
* Progressing cavity pumps WITH BEARING HOUSING.
* Progressing cavity pumps CLOSED COUPLED.
3.3 Motors
Motors can be of different kinds; the pump can be fitted to:
* Electric motors
* Hydraulic motors
* Gearmotors
* Torque converters
3.4 Available configurations
Progressing cavity pumps can be assembled in different configurations, according to the
needs:
* Feedbox and screw feeder
* Vibrating feedbox
* Barrel emptier
* Vertical
Note: customizations include specific inlet and delivery orifices, trailer-mounted base,
simple base, electric board, thermal protections etc.
4 COMPONENTS OF THE PRODUCT
4.1 Rotor

Pag.7 (Funct. and Maint.Manual n.03 – Fourth edition) OMI.EN-PCP001 R01
The rotor may be made of different materials, such as carbon steel and stainless steel. It
may also be coated with hardening surface treatments such as chromium plating, ceramic
treatment, gas and ion nitriding, etc.
4.2 Stator
The stator is built with a steel pipe internally coating with elastomeric material, chemically
compatible with the properties of the fluid to be pumped.
It may be made with different elastomers:
Class MST °C
MATERIAL
MAX
TEMP Class Stator
T4 135 VITON 180°C T4 VITON
T5 100 EPDM 120°C T5 EPDM
T6 85 NBR 90°C T6 NBR - SBR
SBR 90°C
CSM 70°C
MST: Maximum surface temperature allowed for machines of Group II (Cenelec standard
EN 50014).
Note: It is possible to manufacture teflon stators for special applications.
4.3 Couplings
4.3.1 Bearing housing coupling
Using the bearing housing coupling the pump is linked to the motor by the male shaft, and
it is mounted on a cast iron support through rolling bearings.
This configuration allows optimal resistance to the axial thrust towards the motor in those
models working under high pressure. The choice of the motor in this case is not affected
by axial thrust. The final coupling between motor and male shaft is made by elastic joints
with a protective case.
4.3.2 Closed coupling
Closed coupling mounting does not take into account the use of a male shaft, therefore the
hollow shaft of the pump is linked directly to the motor male shaft. In this case, it is
necessary to use motors (or motoreducer in the case) capable of standing axial stresses
coming from counter-pressure reactions during pumping.

OMI.EN-PCP001 R01 (Funct. and Maint.Manual n.03 – Fourth edition) Pag.8
Note: It is possible, for a special series of feedbox pumps, to link the propeller shaft
directly to an angular worm screw gearmotor, without any support.
4.4 Connecting rod joints
Depending on the type of pump, the connecting rod can use different types of joints (see
par. 9.3):
* Type SN1: Pin joint with elastomeric sleeve for smaller pumps.
* Type SN2: Universal joints with elastomeric sleeve and changeable bushing.
* Type SN3: Homokinetic joint with elastomeric sleeve.
* Type SN4: Pin joint with dual elastomeric sleeve and changeable bushing.
* Type SN5: Universal joint with elastomeric sleeve and changeable bushing for high
power.
* Type SN6: Universal joint with elastomeric sleeve and changeable bushing.
* Type SN7: Open Pin joint for use with foods without sleeve.
* Type SN8: Pin joint with short bell and flat sleeve.
* Type SN9: Pin joint with short bell for high power.
* Type SN10: Pin joint with short bell type “C”.
4.5 Sealing systems
The liquid sealing systems may change according to the type of fluid and to the
technologic conditions of pumping. The following types are available (see par. 9.4 and
Service manual):
* Type TEN 01: Packing seal.
* Type TEN 02: Fluxed packing seal.
* Type TEN 03: Oil seal.
* Type TEN 04: Single mechanical seal.
* Type TEN 05: Double fluxed mechanical seal.
* Type TEN 06: Mechanical seal for food application.
* Type TEN 07: Oil seal for worm gearmotors.
* Type TEN 08: Mechanical seal for food application with bearing.
* Type TEN 09: Mechanical seal with washing quench.
* Type TEN 10: Single mechanical seal (for pump type 010).
Note: Mechanical seals can be fluxed, or employ quench techniques.
On request, it is possible to manufacture mechanical seals complying with API 610
standards.
4.6 Accessories

Pag.9 (Funct. and Maint.Manual n.03 – Fourth edition) OMI.EN-PCP001 R01
All pumps may be equipped with accessories to improve their performance and in order to
improve safety of plant.
4.6.1 Dry-run protection
The protection against dry run prevents stator damage whenever the liquid is missing. A
thermal sensor is fitted to the stator, and linked to the electric board. If there is no fluid in
the stator, the stator rubber overheats and the increase in temperature activates the
electric circuit, which stops the motor. This device may be installed subsequently.
4.6.2 Protection against delivery overpressure
The overpressure protection consists of a security valve set to the desired pressure and a
bypass pipe which closes delivery or reduces the flow in case the pump may not be
stopped.
4.6.3 Return valve in delivery
In case it is necessary to convey part of the product back to the tank in order to mix or
make the product more homogeneus, it is possible to fit a valve in the delivery.
4.6.4 Electric board
Upon request, pumps can be controlled by an elecric board, consisting of a main switch, a
pilot light, a liter counter, two-position forward/backward selector and a reset emergency
switch. The boards are also equipped with a safety lock. All boards are supplied in
compliance to the low voltage equipment directive 2006/95/CE.
5 PACKING, TRANSPORT, STORAGE
5.1 Packing and transport
Progressing cavity pumps are shipped in containers (boxes on pallets, cases or cages),
unless the customer requires a different system.

OMI.EN-PCP001 R01 (Funct. and Maint.Manual n.03 – Fourth edition) Pag.10
The parcels are marked and supplied with handling instructions.
Upon receipt, check for possible damages.
Transport damages are to be reported immediately to the carrier.
Pumps are to be brought packed as near as possible to the installation site and kept
packed as long as possible.
Horizontal axis pumps, once unpacked, can be lifted exclusively with the base. Use
external holes and eyebolts on the base. (For dimensions, see drawing in the Service
Manual).
Vertical axis pumps can be lifted using the holes in the support plate or eyebolts or in the
bracket. The motor is usually at the top end. (For dimensions, see drawing in the Service
Manual).
WARNING!: do not lift machines with weight on top (with center of gravity above the
lifting point). Make sure they do not capsize.
Vertical axis pumps must never rest in upright position without adequate fixing!
Warning: they may fall! Always arrange them horizontally. Absolutely do not lift the
pump using the motor or reduction gear eyebolts. They are meant for transport of motor
or reduction gear only.
Due to the diversification of configurations, these are to be considered as general
instructions, usually meant for skilled personnel in charge of transport and assembly.
If more detailed instructions were needed, instructions related to specific machine can be
supplied.
For trailer-mounted pumps follow this:
* Before moving machine make sure that the motor is not running and that it can not be
accidentally started.
* Move the unit slowly and carefully, especially if over irregular ground.
Overturning hazard!
* Make sure that the position in the new resting location is steady; lock every stopping
devices on wheels/rolls, in order to avoid unwanted motion.
* Consider the reaction forces and the movements of flexible piping occuring during
pump working.
* Possibly fix the unit with additional wedges.
5.2 Storage
The pumps, unless otherwise agreed, are protected during transport.
In case of prolonged storage prior to the assembly:
•Stator: In case of prolonged stop, the rotor may permamently buckle the stator on
the contact surface (compression-set). This requires a greater pickup torque.

Pag.11 (Funct. and Maint.Manual n.03 – Fourth edition) OMI.EN-PCP001 R01
Therefore, remove the stator, pack it in order to shelter it from light and air, and
store it in a cool, dry place.
•Rotor: Rest it on wooden blocks and cover it for protection against mechanical
damage.
•Shaft packing: Remove the gland, and grease the shaft.
•Stainless steel parts: No protection needed.
•Other non-painted pump parts: Grease.
•Motors: see manufacturer’s instructions.
6 ELECTRIC CONNECTION – PIPELINE CONNECTION
6.1 Installation of motor
6.1.1 Electric connection
The work relating to electric connections shall be carried out by authorized and specialized
personnel.
In order to connect electric equipment to the machine please follows at the directive CEI
EN 60204-1:2005
The power supply must be equipped with a thermal magnetic overload cutout, or a fuse,
and a compulsory earthing system, as mentioned above.
The electric wire shall be double-insulated and fire-retardant and with an adequate cross-
section for every phase. The connecting to the Neutral must be coherent with safety
system of installation plant (TT-TN etc.).
Before starting the pump, check:
tension, frequency and number of phases conform with the electric motor
•motor connections (star/triangle) conform with the alimentation available.
•wire section conform with the amperage concerned.
6.1.2 Pump-motor coupling
6.1.2.1 Close coupled version
The coupling of a progressing cavity pump with its motor is not difficult, though problems
may arise since the mechanical seal (or packing) is installed on the hollow shaft which, if
not coupled to the motor/converter, can easily break the seal.
Therefore, during assembly, it is necessary to be careful not to move excessively the axis
of the hollow shaft. Oil the male shaft of the motor/converter, place it so that its key is in
line with the corrispondant bore.
Engage the propeller shaft until the two flanges (the motor’s and the pump’s) were
connect. Then turn the motor/converter until the bolts holes of the flanges coincide. Let the
pump shaft hit the motor shaft and tighten the grub screw (line it up with the cavity set it up
on the gearmotor shaft).
6.1.2.2 Bearing housing version (with elastic joint)

OMI.EN-PCP001 R01 (Funct. and Maint.Manual n.03 – Fourth edition) Pag.12
Insert the half-joints (or pulleys, if belt drive is employed) at the ends of the shaft without
using a hammer or other tools which may damage parts inside the support. For
assembly, use the threaded hole on the end of the shaft.
The accurate alignment of motor and the male shaft of the pump is an essential condition
for a proper operation.
If the pump is delivered completed, the alignment has already been carried out at the
factory.
Nonetheless, it is possible that during the positioning on the floor a misalignment may
occur, therefore it is necessary to remove the joint cover and check its alignment by
means of a ruler before startup. If the foundation is not properly leveled, the base may
buckle. The tolerances usually allowed in joints used by the NOVA ROTORS™ S.r.l. are:
•Allowed radial variation = 1%
•Allowed angular variation = 1°
6.1.3 Direction of rotation
The direction of pump rotation is shown on the label pump and described on the
confirmation order.
The direction of pump rotation sets the direction of the flow through the progressing cavity
pump.
Any different setup must be agreed with the supplier and approved by the same.
By changing the direction of pump rotation, the product flow reverses.
If the pump turns clockwise, seen from the motor side, it intakes from the orifice at the end
and delivers from the middle one; if the pump turns counterclockwise it intakes from the
middle orifice and delivers from the one at the end (see below)
Usually, the pump can work in both directions, be it mounted with packing or with a
mechanical seal (unless it uses omokinetic joints which allow just one direction).
It is advisable, though, to use the pump turning counterclockwise to prevent that the
packing rings (or the mechanical seal) or other parts were subject to high pressure that
could be difficult to monitor.
The pumps with a mechanical seal, though reversing, shall always turn in the direction
indicated on the pump label.
This direction of rotation shall be preset upon the order while the seal assembled shall be
preset at the factory.
Contact NOVA ROTORS™ S.r.l. if you need to change the direction of rotation for pumps
that use mechanical seal.
IMPORTANT!

Pag.13 (Funct. and Maint.Manual n.03 – Fourth edition) OMI.EN-PCP001 R01
In close coupled versions, it is necessary to check periodically that the shaft grub screw
were well tightened and fits properly in the propeller shaft cavity, especially if the pump is
employed in both directions. To this purpose, see par. 6.1.2.1 of this Manual.
6.2 Pipe assembly
6.2.1 Important premise
•Intake and outlet pipe diameters must be adequate, according to viscosity and
delivery involved.
•Accurately clean the pipes before connecting them to the pump.
•Pipes must be connected to the pump so that no external force may be applied to
the pump itself.
•Fit adequate compensators between pump and pipes to protect the pump from
vibrations which may damage the pump body.
•Intake and outlet pipes shall be fitted so that, the pump is not working, there is
some fluid upstream and downstream, in order to ensure that there is always
enough fluid in the pump to provide lubrication at startup.
•Minimize the air intake in the body pump.
Note: In case fluxed packing glands or fluxed mechanical seals or quenches were used,
the feeding system connections and system tuning must to be carried out prior to the first
startup.
6.2.2 Max allowed pressure
Unless otherwise set out in the order confirmation, it is understood that the maximum
pressure inside the pump body (i.e. with pump turning clockwise) is 6 bar per stage.
The maximum allowed pressure at delivery is related its features:
•flange: not exceeding nominal pressure (i.e. PN 16)
•female thread: not exceeding 25 bar
•sanitary male thread according to DIN 11851, up to DN 100:
single and double stage pumps: not exceeding 12 bar
multiple stage pumps: not exceeding 25 bar
Other configurations: In any case not exceeding 6 bar per stage of the stator being used.
6.2.3 Useful advice
It is advisable to fit to the pipe union a stub pipe of L length. This will allow the replacement
of the stator without the need of disassembling the pump. The L value is shown in the
table below, according to the size of the pump and the number of stages:
LENGTH L

OMI.EN-PCP001 R01 (Funct. and Maint.Manual n.03 – Fourth edition) Pag.14
7 STARTUP
IMPORTANT!
•Never operate the pump without product - this is mandatory, otherwise the
stator, made of elastomeric material will overheat and may burn. A few seconds are
enough to cause damage to the stator.
•The eccentric screw pump is of the volumetric kind, therefore it shall NEVER be
operated with a closed delivery valve. Since the theoretical pressure is infinite,
this would cause excessive stress with partial or total damage to the pump or
piping.
•Before startup, check that the direction of rotation were correct.
7.1 Advice for optimal operation
To achieve long life and high performance, it is useful to follow these recommendations:
•The pump is self-priming, but it is advisable to fill its body with the liquid to be
pumped before the first startup.
•Control the rate of delivery by modifying the rpm of the motor instead of setting
choking valves.
•Install an immediate stop device in case of absence of liquid at intake, by means of
a temperature sensor on the stator, to stop the pump after a few seconds of dry
operation.
7.2 Pumps for alimentary use
The startup of pumps to be used with food requires the plant to be perfectly clean.
Cleaning may be performed in two ways:
PUMP 1 STAGE 2 STAGE 3 STAGE 4 STAGE
010 - 80 - -
015 80 160 - -
020 110 170 - 360
030 160 300 - -
040 200 420 - -
050 260 - 530 -
053 - - - 530
055 270 550 - 980
060 440 - - 1230
062 320 630 - -
080 440 880 - -
120 500 - - -
200 540 - - -
300 540 1050 - 2110
400 660 1260 - -
500 820 1580 - -

Pag.15 (Funct. and Maint.Manual n.03 – Fourth edition) OMI.EN-PCP001 R01
•Disassemble the pump and wash every part of it with suitable detergent. Re-
assemble the parts making sure they stay clean.
•Perform Cleaning in Place (CIP) if the pump is suitable for this kind of cleaning.
7.2.1 When to perform cleaning
•Before startup
•After a prolonged stop
•After replacing parts
•After use if a prolonged stop is foreseen
Several companies supply products for CIP cleaning. Make sure the products used are
compatible with the material to be pumped.
7.2.2 CIP cycle
•Pre-washing with clean water, to empty the pump
•Basic washing with caustic soda (1-2% at 60-80°C for 10-20 min.)
•Intermediate washing with clean water for 5-10 min.
•Washing with nitric acid (1-1.5%) at 50-70° C for 5-10 min.
•Final washing with clean water for 5-10 min.
Note: The washing speed of liquid detergents should not exceed 2 m/s at any point.
In this cycle the stator is subject to high chemical and thermal stress. Therefore, in this CIP
cycle the pump shall stop and restart, that is, change the relative position of rotor and
stator every 2-3 minutes, turning just a few times to make sure that every part of the stator
gets cleaned.
7.3 Temporary rest
After stopping the pump, empty it and possibly wash it if:
•The fluid may solidify.
•The mechanical seal may get encrusted.
•The liquid inside the pump may freeze due to the low ambient temperature.
7.3.1 Procedures
7.3.1.1 Stator
In case of prolonged stop, the rotor may permanently deform the stator on the contact
surfaces (compression-set). In this case a greater pickup torque is required at restart.
It is therefore better to dismount the stator from the pump, pack it to shelter it from air and
light and store it in a cool, dry place.
7.3.1.2 Rotor
After the stator has been disassambled, rest the rotor on wooden blocks and cover it to
prevent damage.
Before reassembly, degrease and clean the rotor to prevent conflicts with the stator
material or with the product to be pumped.

OMI.EN-PCP001 R01 (Funct. and Maint.Manual n.03 – Fourth edition) Pag.16
8 MAINTENANCE
IMPORTANT: All maintenance and cleaning operations must be performed
with the machine at a standstill and cut out from any energy source.
After a stop and before restarting, the machine must be inspected to determine the cause
of the stop command, and act with appropriate measures in order to prevent that from
happening again.
The inherent vibrations of a progressing cavity pump are below 2.5 m//sec², therefore they
hardly cause risk or trigger possible failures. The vibrations, though, may lead to the
loosening of the screws of the pump. It is therefore essential to regularly check the
tightening of them.
8.1 Superficial cleaning
It is important to schedule regular cleaning operations, depending on the liquid to be
pumped. The pump may be cleaned:
•Through the cleaning windows if present on the pump body.
•Manually, disassembling the pump
•Automatically (CIP) for pumps with suitable connectors.
8.2 Stators and sealing systems
8.2.1 Stators
Approx. every 900 hours of operation, it is necessary to check the wear, especially for the
stator and the sealing system (packing or mechanical seal).
The frequency of control operations will be determined according to the wear of both of
them, not exceeding anyway 1500 working hours.
8.2.2 Seals
8.2.2.1 Packing seal
Packing seals limit the leakage of product, but do not prevent it entirely. A small leakage is
necessary to prevent excessive friction and subsequent possible overheating.
At startup, after replacement, tighten the gland bush lightly until it is set and in ideal
working conditions (for 10-15 min.), then tighten it more strongly to obtain the smallest
possible leakage.
In case the pack were excessively compressed, the following damages may arise:
•Dry working
•Burnt pack
•Scored shaft (with subsequent leakage of fluid).

Pag.17 (Funct. and Maint.Manual n.03 – Fourth edition) OMI.EN-PCP001 R01
NOTE: The packing seal is in optimal working condition if constantly damped by the
product to be pumped.
8.2.2.2 Single mechanical seal
The type and brand of the mechanical seal used is specified in the order confirmation. In
case of significant leakage, check the surfaces of the seal faces and seat. Replace them if
necessary.
8.2.2.3 Mechanical seal for vertical pumps
Use particular caution on vertical pumps with motor on top (type SV/VM).
At startup, the mechanical seal has not yet been in contact with the fluid and briefly works
dry until the air in the pump body has been expelled.
At first startup or after a prolonged stop, lubricate the mechanical seal before starting the
pump.
Lubricate with water, glycerine or oil, depending on the product to be pumped: check for
compatibility with the elastomers of the mechanical seal.
8.3 Control and replacement of articulated joints
The driveline joint is one of the most stressed parts of the pump, therefore needs regular
and adequate controls. On any kind of joint, it is always necessary, though the pump may
work normally, to immediately replace damaged sleeves, even if the damage is slight.
Sleeves of any kind are to be kept in warm water for some minutes before replacement, in
order to soften them and ease the fitting to both ends of the joint and prevent damage on
the elastomer they are made of.
8.4 Lubrication
8.4.1 General
The NOVA ROTORS™ progressing cavity pump is supplied with lubricant for about 3250
working hours. In case of replacement of parts involving lubrication, it is advisable to re-
lubricate. To this purpose, see the table below:
Universal joints: VN 2461 C
Chrome steel joints (Universal joint and Pin joint): Agip SM2 - Esso Beacon Q2
AISI stainless steel joints (Universal joint and Pin joint): Agip SM2 - Esso Beacon Q2
Bearings: Agip MU3
Rubber stators for food: Agip vaseline 1718
Steel Universal Joints Molycote VN 2461 C
Chromed steel, universal joint and pin joint Agip SM2 - Esso Beacon Q2
Stainless steel, universal and pin joints Agip SM2 - Esso Beacon Q2
Bearings Agip MU3
Food grade stators Agip vaseline 1718
8.4.2 Bearings

OMI.EN-PCP001 R01 (Funct. and Maint.Manual n.03 – Fourth edition) Pag.18
The male shaft bearings are greased at NOVA ROTORS™ . In case they were removed,
their seat shall be filled with grease according to the table above.
8.4.3 Propeller shaft joints
Pin joints with sleeve are to be periodically lubricated.
Moreover, every time parts were replaced with original spare parts, their grease shall be
replaced.
IMPORTANT: The pumps that uses sleeves over joints for food are supplied with
food-compatible grease.
8.4.4 Motor variator See Service Manual
8.5 Malfunctioning
Below you can find a synthetic table. Malfunctioning References:
A The pump does not work F The pump stops
B The pump does not intake G Faulty stator
C Wrong delivery H Faulty rotor
D Uneven flow I The seal leaks
E Noisy pump J Low delivery pressure
A B C D E F G H I J POSSIBLE CAUSE
1 X X New stator and rotor are stuck together
2 X X Faulty electrical contact
3 X X X X X Excessive delivery pressure
4 X X X X Unknown matter in the pump
5 X X X X X High temperature, the stator squeezed
6 X X X Stator of wrong material. Check the order
7 X X X X X Product granulometry too high.
8 X X X X X X X The product sediments when the pump is
stopped
9 X X X Air leakage at intake
10 X X X X Difficult intake
11 X X X X Air intake from seal or packing
12 X X X X Too Low speed
13 X X X X Wrong direction of rotation
14 X X X Available NPSH below required
15 X X X X X X The pump is working dry
16 X X X The stator is faulty – burned-over
17 X X X X X Spoilt stator. Check rubber
18 X X X X X Faulty rotor
19 X X X X Faulty connecting rod
20 X X The pump is not aligned to the elastic joint
21 X X Broken connecting rod
22 X X Spoilt bearings
23 X X X Too high speed
24 X X X X X Excessive viscosity
25 X X X X X X X The gland needs to be adjusted
26 X X X Inadequate sealing system

Pag.19 (Funct. and Maint.Manual n.03 – Fourth edition) OMI.EN-PCP001 R01
Reference for malfunctioning removal:
1) Fill the pump with suitable product, gliceryn or soap (DO NOT USE any kind of oil if an
EPDM rubber stator is used).
2) Check on the order for details concerning electric connections and compare.
3) Measure pressure with a manometer and compare that with the value signed in the
order.
4) Remove unknown material and replace damaged parts.
5) If the temperature can not be lowered, install a downsized rotor.
6) Check if the fluid corresponds to the order, change stator rubber.
7) Increase the liquid percentage. Install a grid at intake.
8) Clean the pump and repeat the operation after each single use.
9) Increase the level of liquid at intake to prevent air intake.
10) Check seals and carefully tighten the pipes unions.
11) Tighten or replace the gland. If a mechanical seal is used, carefully clean and replace
it if necessary.
12) Increase rpm.
13) Modify electric connections.
14) Increase the pressure at the inlet lowering the pump position and lower the inlet fluid
temperature.
15) Fill the pump, install a device preventing dry working.
16) Replace the stator.
17) Replace the stator, check if the fluid corresponds to the order and if necessary change
stator rubber.
18) Replace the rotor and try to identify the cause, which may be abrasion, corrosion or
cavitation.
19) Replace worn parts.
20) Re-align pump and elastic joint.
21) Replace broken part and re-align.
22) Replace bearings, lubricate and tight.
23) Lower rpm through variator.
24) Check viscosity and compare it with the order.
25) Check specific weight and compare it with the order.
26) Choose a different mechanical seal or packing.
Note: For any query, please contact NOVA ROTORS™ or our local agent.
9 DISASSEMBLY AND ASSEMBLY OF COMPONENTS
PREMISE
1. Comply with the safety measures set out in Chapter 1 of this Manual.
2. The pump and its piping shall be emptied and cooled.