Biral NT Series Manual

1
Operating and Maintenance Instructions VM No.: 460.0002 GB
Edition: 07.00
Ident No.: 550 088
Volute–Casing Centrifugal Pumps Retain
for future
Series NT use!
Order No.: Pump Ident. No.:
Machine No.: Pump Type:
Operating data, dimensions and other additional information can be found in the order–specific part of the
documentation.
These Operating and Maintenance
Instructions contain information from
the pump manufacturer. They may need
to be supplemented by instructions of
the operator company for its personnel.
These instructions do not take account
of specific information relating to opera-
tion and maintenance of the process
plant into which the pump is integrated.
Such information can only be given by
the persons responsible for construc-
tion and planning of the plant (plant
manufacturer).
Such specific instructions relating to
operation and maintenance of the
process plant into which the pump is
integrated have priority over the
instructions of the pump manufac-
turer. The plant manufacturer must
on principle observe the limits of
use!
Refer to the operating instructions of
the plant manufacturer!
Contents
1. General
2. Safety
3. Transportation and Intermediate
Storage
4. Description
5. Installation/Mounting
6. Start–up/Shutdown
7. Maintenance/Repair
8. Operating Faults, Causes and
Remedial Action
9. Associated Documentation
Important note:
This operating manual is to be supplemented
by the order–related informations.

NT
2
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
1 General
1.1 Pump designation
The exact designation can be found in the order–spe-
cific documents (see data sheet).
1.2 Proper use
Information on proper use of the pumps is provided in
the technical data sheet.
The pumped liquid must not contain any abrasive con-
stituents nor corrode the pump materials.
1.3 Types of construction
The pumps are supplied in various designs, differing
mainly in the shaft seals and the materials.
1.4 Performance data
The exact performance data can be taken from the or-
der data sheet and/or acceptance test report.
1.5 Warranty
Our warranty for shortcomings in the supply is laid
down in our delivery conditions. No liability will be un-
dertaken for damages caused by non–compliance with
the operating instructions and service conditions.
If at any later date the operating conditions change (e.g.
different fluid conveyed, speed, viscosity, temperature
or supply conditions), it must be checked by us from
case to case and confirmed, if necessary, that the pump
is suited for those purposes. Where no special agree-
ments were made, pumps supplied by us may, during
the warranty period, only be opened or varied by us or
our authorized contract service workshops; otherwise
our liability for any defects will cease.
1.6 Testing
Prior to leaving our factory, all pumps are subjected to
a leak and pressure test. Additional tests will only be
performed on request.
1.7 Availability
As a matter of principle, we recommend stocking
replacement pumps and withdrawable units (hydraulic
action system) where the supplied pumps are a
decisive factor in maintaining a production or delivery
process. In this way downtimes can be avoided, or
reduced to a minimum.
1.8 Pressure limit
The sum of inlet pressure and maximum delivery pres-
sure must not be greater than the permissible internal
pump pressure (see data sheet).

NT
3
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
2Safety
These operating instructions contain basic safety
instructions for installation, operation and
maintenance. It is therefore essential that they are read
by fitters and all specialist staff and customer personnel
prior to installation and start–up. They must always be
kept at hand at the place of installation.
The special safety instructions contained in the other
chapters must be observed in addition to the general
safety instructions in this chapter.
2.1 Identification of safety instructions in the
operating manual
The safety instructions contained in these operating
instructions which represent a danger to personnel if
not complied with are specially marked by the general
danger symbol:
Warning symbol
as per DIN 4844–W9
Warning of danger from electric voltage is indicated as
follows:
Warning symbol
as per DIN 4844–W8.
Instructions which are essential to avoid endangering
the machine and its operation are marked by the word
ATTENTION
Instructions affixed directly to the machine such as
SDirectional markers
SSigns for fluid connections
must always be observed and maintained in fully
legible condition at all times.
2.2 Personnel qualification and training
The operating, maintenance, inspection and mounting
personnel must be appropriately qualified for the duties
assigned to them. The scope of their responsibilities,
competency and supervisory duties must be closely
controlled by the customer. If the personnel do not have
the required knowledge, they must be trained and
instructed. If required, this may be provided by the
manufacturer/supplier on behalf of the customer. The
customer must additionally ensure that personnel fully
understand the content of the operating instructions.
2.3 Dangers in the event of non–compliance with
safety instructions
Failure to comply with the safety instructions may result
in danger to persons, and place the environment and
the machine at risk. Non–compliance with the safety
instructions will lead to the loss of any claims for
damages.
Non–compliance may result in the following dangers:
SFailure of important functions of the plant
SFailure of specified methods for maintenance and
servicing
SDanger to persons resulting from electrical,
mechanical and chemical effects
SDanger to the environment resulting from leakage of
hazardous substances
2.4 Responsible working practices
The safety instructions contained in these operating
instructions, current national accident prevention
regulations, as well as internal working, operating and
safety rules of the customer, must be observed.
2.5 Safety instructions for the user/operator
SHot or cold machine parts representing a danger
must be protected against accidental contact on
site.
SProtection against accidental contact for moving
parts (such as the coupling) must not be removed
while the machine is in operation.
SWhen operating pump aggregates in a dust–laden
environment (e.g. milling, chipboard manufacture,
bakeries), the surfaces of the pumps and motors
must be cleaned at regular intervals, depending on
local conditions, in order to maintain the cooling
effect and eliminate the possibility of spontaneous
combustion. Please also see explosion protection
regulations (ZH 1/10).
SLeakage (e.g. from the shaft seal) of hazardous
substances being handled, such as explosive, toxic
or hot materials, must be discharged in such a way
that no danger to persons or the environment is
created. Legal regulations must be observed.
SDangers from electrical energy must be eliminated.
For details in this regard, please refer to VDE and
local power company regulations.

NT
4
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
2.6 Safety instructions for maintenance, inspection
and installation
The operating company must ensure that all
maintenance, inspection and installation tasks are
performed by authorized and qualified specialist
personnel who have thoroughly studied the operating
instructions.
Work on the machine is only to be carried out when the
machine is at a standstill. The procedure for shutting
down the machine described in the operating
instructions must always be followed.
Pumps or aggregates handling fluids which are
detrimental to health must be decontaminated. All
safety and protective devices must immediately be
refitted and made operational on completion of the
work.
The instructions under Section 6.1, ”Preparation for
start–up”, must be observed before restarting.
2.7 Unauthorized conversion and production of
replacement parts
Conversion or modification of the machines is only
permissible after consultation with the manufacturer.
Original replacement parts and accessories approved
by the manufacturer are intrinsic to safe operation. If
other parts are used the manufacturer cannot be held
liable for the consequences.
2.8 Unacceptable modes of operation
The operational safety of the machine supplied is only
ensured when it is used in accordance with Section 1 of
the operating instructions. The limit values given on the
data sheet must not be exceeded under any
circumstances.
3 Transportation and Intermediate Stor-
age
3.1 Packaging
Attention must be paid to the figurative markings on the
packaging.
The suction and pressure side and all auxiliary connec-
tions must always be closed during transportation and
storage. The coverings must only be removed im-
mediately before connecting the pipeline.
3.2 Transportation
The pump or pump aggregate is to be safely trans-
ported to the place of installation, if required by means
of lifting gear.
The regulations for lifting loads in accordance with
VBG 9a must be observed. Crane and sling equip-
ment must be adequately dimensioned. Sling
equipment must not be secured to the lifting eyes
of the motor, except as additional protection
against overturning in the event of nose–heavi-
ness.
Transportation to and at the installation site
Make sure that the unit is transported safely and in a
stable position. Overturning due to nose–heaviness
must be prevented.
Transport damage
Check the pump for damage on receipt.
Any damage detected must be notified im-
mediately.

NT
5
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
3.3 Preservation / Storage of centrifugal pumps
3.3.1 Preservation
In the case of storage or prolonged standstill, the
pumps must be protected against corrosion. In those
cases, an outside and inside preservation is to be pro-
vided. The durability of the protection against corro-
sion, which is limited in time, depends on the composi-
tion of the preservative to be applied and the storage
conditions. Under normal circumstances the pumps
have no special preservative.
At an additional charge we can, however, supply
pumps and replacement parts ex factory with a preser-
vative adequate to the planned storage period.
3.3.1.1 Outside preservation
The outside preservative should be applied by painting
or spraying with a spray gun.
Points of preservation:
All bright and unvarnished parts (e.g. shaft ends, cou-
plings, flange facings, valve and manometer connec-
tions).
3.3.1.2 Inside preservation
(Not required for pumps made of stainless materials.)
Internal preservation is applied by painting, spraying
using spray guns, filling/dipping and subsequent drain-
ing. Finally, the suction and outlet branches as well as
all other supply and discharge branches must be
sealed with dummy flanges or dummy plugs (plastic
caps).
Points of preservation:
All bright parts inside the pump (e.g. pump casing in-
side, bearing bracket, shafts, impellers and diffusers).
3.3.1.3 Storage times
Depending on the required storage period and the sur-
roundings, we recommend the use of preservatives
from Valvoline GmbH, Hamburg.
Storage in a closed, dry and dust–free room
Storage time up to 6 months up to 12 months over 12 months À
Internal preserrvation Tectyl 511 M Tectyl 511 M Tectyl 506 EH
External preservation Tectyl 511 M Tectyl 511 M Tectyl 506 EH
Storage in the open–air, central European climate
Storage time up to 6 months up to 12 months over 12 months
Internal preservation Tectyl 542 Tectyl 542 Tectyl 506 EH
External preservation Tectyl 542 Tectyl 506 EH Tectyl 506 EH
Storage in the open–air, tropical climate, aggressive industrial air or
proximity to the sea
Storage time up to 6 months up to 12 months over 12 months Â
Intermal preservation Tectyl 542 Tectyl 542 Tectyl 506 EH
External preservation Tectyl 506 EH Tectyl 506 EH Tectyl 506 EH
ÀInternal and external preservation must be renewed after 48 months at the latest.
ÁExternal preservation must be renewed after 18 months at the latest.
Internal preservation must be renewed after 48 months at the latest.
ÂExternal preservation must be renewed after 12 months at the latest.
Internal preservation must be renewed after 48 months at the latest.
Note: The preservatives listed are to be regarded as a
recommendation. Alternatively, technically equivalent
products from other manufacturers can be used.
When handling preservatives, the safety hints con-
tained in the relevant DIN safety data sheets and those
of the manufacturer must be complied with.
3.3.1.4 Depreservation
Prior to setting the pump in motion, the inside preserva-
tion must be removed.
Environmentally compatible disposal must be en-
sured.
Preservatives can be removed with wax solvents, pe-
troleum ether, diesel, petroleum or alkaline cleaners.
However, the simplest method is to use a steam clean-
er.
Recommendation for Tectyl 506 EH: Allow petro-
leum ether to act for 10 minutes before any further ac-
tion.
Pumps that are used in the food or drinking water sector
must be dismantled and thoroughly cleaned prior to de-
preservation.
A suitable solvent that is compatible with the liquid to be
pumped (drinking water/food) can be used as the
cleaning agent, e.g. Spiritus, Ritzol 155 or suds with a
high alkaline content. Steam cleaning is ideal.
After a prolonged storage period (more
than 6 months), all elastomers (O–rings,
shaft seals) must be checked for elasticity of shape.
Embrittled elastomers must be replaced. EP rubber
elastomers (EPDM) must be replaced on principle.
3.3.2 Storage
During storage of the pump, the suction and outlet
branches and all other supply and discharge branches
must always be closed with dummy flanges or dummy
plugs.
Storage should be in a dry, dust–free room. During stor-
age, the pump should be cranked at least once a
month. During this process, parts such as the shaft and
bearings should change their position.
3.3.3 Monitoring of the preservation status
The preservation status should be checked at regular
intervals.
The preserved areas must be inspected every 6
months and re–treated, if necessary.
We cannot accept any liability for defects
that arise due to incorrect preservation
treatment.
3.3.3.1 Monitoring of preservation
The preservation must be checked at regular intervals.
The preserved areas must be inspected every 6
months and re–treated, if necessary.
We cannot accept any liability for defects
that arise due to incorrect preservation
treatment.

NT
6
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
4 Description / Principle design of the pump
The pictorial presentation may not correspond with the pump supplied.
The actual design will be stated in the specific order documents.
Volute casing
Impeller Bearing bracket
Shaft
Contact protection to EN 809
by coupling guard
Shaft seal
Earthing connection to EN 809
at the base plate

NT
7
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
5 Installation/Mounting
5.1 Installation
For installation methods and locations, please see in-
stallation drawing.
Other methods of installation are not permissible
without prior consultation with the manufacturer.
When installing the pump, please ensure
that the cooling air from the motor fan can
flow unimpeded over the bearing bracket to the casing
cover.
5.1.1 Place of installation
Temperature: min. –20 C
max. +40 C
relative air humidity:
permanent max. 85 %
temporary max. 100 %
Installation height: max. 1000 m above NN
For data differing from this, please consult the manu-
facturer. Intensive vibrations in the vicinity of the
pump unit can lead to bearing damage and
must therefore be avoided.
Pumpes used for the delivery of water
must be installed so that they are protected
against freezing.
5.1.2 Protective devices
In order to prevent injuries due to burns, at pumping
liquid temperatures higher than 60C protective de-
vices in accordance with EN 809 must be provided on
site.
Heat insulation
Only the volute housing may be insulated
with heat insulating material. In order to
enable optimum heat dissipation no other pump com-
ponents may be insulated.
5.2 Foundation
5.2.1 General
The foundation may be a floor/concrete base or a load–
bearing steel foundation frame.
The foundations must be constructed in
such a way that they can take the weight of
the pump unit and all operating forces that occur.
5.2.2 Characteristics of a steel foundation frame
A steel foundation frame must be constructed in such a
way that pump feet or base plate are supported evenly
and can be secured with screw fixings.
If the base plate is only supported at four
points the pump aggregate will hang down
in the middle. This will affect the alignment of the cou-
pling and may also lead to severe noise being gener-
ated.
5.2.3 Characteristics of a floor/concrete foundation
The foundation must be horizontal, flat and clean, and
be capable of bearing the full load upon it.
Note: Concrete foundations must be executed with
standard concrete of strength class B 25 as a minimum.
5.3 Alignment of the pump aggregate
The pump aggregate must be aligned to its pre–set
height and system dimensions. This is done using sui–
table steel shims, arranged directly adjacent to each fi–
xing bolt.
The overall height of the steel shims is determined by
the established system dimensions of the plant. The
steel shims and the base plate must be positioned
evenly and securely.
If the fixing holes are more than 750 mm apart, we re–
commend fitting additional steel shims in the middle of
the base plate.
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Steel shims Foundation
Base plate
==
> 750
Fig. 1: Alignment with steel shims
Horizontal alignment of the aggregate is produced by
way of flat–machined surfaces on the pump using a
machine spirit level. Measurements are taken in longi–
tudinal and transverse directions of the pump aggre–
gate.
Permissible deviation: max. 1 mm per 1 m length.
5.3.1 Fixing the pump aggregate
In order to prevent deformation of the base plate/pump,
this must first of all be screwed tightly at three points.
Before tightening the rest of the screws, spacers
should again be positioned around the screw, in order
to balance out the unevenness of the seating.
The prescribed tightening torque (Section
7.2.3) must be observed.
Precise details on the shape and dimension of the fixing
are provided in the installation drawing.
5.3.2 Checking the alignment
After aligning and tightening the screws, it must be
possible to turn the pump and drive by hand, without
any strain.
Note: The pump unit should not be welded to the base
for technical installation reasons.

NT
8
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
5.4 Checking the coupling alignment
5.4.1 Checking the coupling alignment in case of hori-
zontal setup on base plate
A complete delivered pump aggregate has been care–
fully assembled at the factory. After proper installation,
and prior to start–up of the pump aggregate, the align–
ment of the coupling must be checked.
The check can be made with a straight–edge and a
feeler gauge, or with other suitable equipment (such as
a laser alignment device).
The measurements are taken in two planes, each offset
by 90_, on the circumference of the coupling.
If a height, lateral or angle offset is detected between
the two coupling halves, the drive motor should be re–
aligned such that the coupling halves are flush with
each other (level out with flat packing shims as neces–
sary).
The gap between the two coupling halves must be the
same all round the circumference of the coupling. The
specified gap is shown in the installation diagram.
The spacing between the straight–edge laid over both
coupling halves and the respective shaft must be the
same all round the circumference.
Straight–edge
Feeler gauge
Figure 5.2: Alignment of the coupling with
straight–edge and fee–ler gauge
For couplings with a distance piece (removable coup-
lings) the alignment of the coupling can be checked
with dial gauges.
Figure 5.3: Alignment of the coupling with dial gauges
Note: The permissible axial and radial deviation,
measured on the front face of the coupling and the
coupling circumference respectively, may be max.
0.1 mm, but as far as possible should be kept below
0.05 mm.
Whe the fixing bolts have been aligned and tightened
the pump/drive motor unit must be able to be spun by
hand without pressure points.
Out–of–flush errors on the coupling may
lead to heavier wear of the coupling, the
anti–friction bearing and the shaft seal, and even cause
the shaft end to be torn off.
5.4.2 Coupling alignment of special designed couplings
(if used)
Refer to the operating instructions of the coupling
manufacturer.
5.5 Assembly of pump and drive motor
If the aggregate is only assembled at the place of use,
the following work is to be performed:
1. Coat the pump and motor shaft ends with a fine film
of molybdenum disulfide (e.g. Molykote) and insert
keys.
2. Push on the coupling halves on the pump and motor
side with the aid of a pusher device until the shaft
end is flush to the coupling hub.
If no puller is available, heating the coupling halves
to approx. 100C (without rubber buffer) facilitates
pushing. The possibility of shock and stress on
the pump and drive motor components
must be eliminated.
3. Tighten the grub screw on both coupling hubs.
4. When assembling the pump and motor, make sure
the specified gap between the coupling halves is
maintained (see our installation drawings).
5. In the case of horizontally mounted pump
aggregates fixed on a base plate or directly on the
foundation, the coupling must be aligned as
described in Section 5.4.
6. Mount the contact protection.
According to accident prevention regulations, the
pump must only be operated with a protection
against accidental contact.
5.6 Space required for maintenance and repair
The pump must be accessible from all
sides in order to be able to carry out
necessary visual inspections.
Adequate space must be provided for maintenance
and repair work, in particular for removal of the drive
motor or of the complete pump aggregate. It must also
be ensured that all pipelines can be attached and
removed without hindrance.

NT
9
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
5.7 Laying the pipelines
5.7.1 Nominal widths
The nominal diameters of the pipelines need not
necessarily correspond to those of the inlet and outlet
branch, however, they must not be smaller. Different
nominal diameters of suction branches and suction
pipelines are to be compensated by centric transition
pieces. Formation of air bags is to be avoided.
min. 5xDNs
min. 5xDNd
Figure DN 1
Recommendation for straight pipeline length
before and after the pump
Shorter pipelines on the suction side are
possible, but may lead to a deterioration of
the hydraulic performance data. Shorter pipelines on
the discharge side are possible, but may lead to in-
creased noise development.
5.7.2 Changes in cross–section and direction
Sudden changes in cross–section and direction, as
well as bends with a bend radius less than 1.5 times the
interior pipe width, must be avoided.
5.7.3 Supports and flange connections
The permissible pipeline forces according
to the installation drawing must not be ex-
ceeded in any operating status.
We therefore recommend on principle that a calculation
of the pipeline forces is performed, which takes into
consideration all operating status (e.g. cold/warm,
empty/full, depressurised/pressurised, etc.). Changes
in position of the pump flange must be observed.
Pipeline supports must always be free sliding and must
not rust in (check regularly).
How to assess a pipeline connection
To conduct an assessment, the pipeline must be de-
pressurised, completely drained and cooled. The
pumping liquid must be disposed of with respect for the
environment.
SDisconnect the pipeline from the pump at the con-
necting flanges.
SAfter disconnecting the connecting flanges, the
pipeline must be freely movable in all directions in
the area of expected expansion.
Note: up to Ø150 mm by hand
from Ø150 mm with small lever
SThe flanges must lie plane–parallel.
5.7.4 Cleaning pipelines prior to attachment
Prior to assembly, all pipeline parts and valves must be
thoroughly cleaned.
No impurities must reach the pump from
the pipeline system (e.g. welding beads,
residues from preservatives, etc.).
Flange gaskets must not protrude inwards. Blanking
flanges, plugs, protective film and/or protective paint on
flanges and seals must be removed completely.
Filters on suction side must be cleaned
regularly. We recommend monitoring with
differential manometer and/or contact manometer.
5.7.5 NPSH observation
The NPSH conditions of the system must be adapted to
the respective pump requirement (NPSHreq.).
An essential condition is fulfilled if the system NPSH va-
lue (NPSHavail.) is at least 0,5 m above the pump
NPSH value (NPSHreq.). The NPSHreq. can be taken
from the characteristic curves of the relevant pumps.
The applicable NPSH values in the char-
acteristic curves are for water with 20C.
For other media and/or temperatures, the NPSH value
may deviate from the characteristic curves.
Uncertainties in the determination of
NPSH conditions, particularly for media
other than water and/or other temperatures, must be
compensated for by increased safety factors (please
consult the manufacturer).
5.7.6 Suction and inlet pipeline
In order to avoid the formation of air bags, the suction
and inlet pipeline must be laid rising to the pump.
5.7.6.1 Foot valve and suction basket (suction mode)
For suction operation, the suction pipeline must be
equipped with a foot valve preventing the pump and
suction pipeline from running empty while at rest.
The suction basket must be attached so that neither dirt
from the sump nor air from the fluid level can enter.
5.7.6.2 Stop valve (inlet mode)
A stop valve is to be installed in the inlet pipeline. It must
be fully open during operation (see figure DN 1).
5.7.7 Pressure pipeline
5.7.7.1 Stop valve in the pressure pipeline
A stop valve should be installed in the pressure pipe-
line.
5.7.7.2 Non–return valve in the pressure pipeline
The pump must not run backwards. It is recommended
that a non–return valve is fitted between the pressure
branch and the stop valve.
5.7.7.3 Bleeding
In the pressure pipeline, bleeding facilities should be
provided at the highest point and in front of the non–re-
turn valve.
5.7.8 Auxiliary connections
The positions of the auxiliary connections on the pump
are shown in the installation drawing. All auxiliary
pipelines must be connected in accordance with the
installation drawing, stress–free and sealed.

NT
10
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
5.8 Safety and control devices
5.8.1 Manometers
We recommend to provide suitable pressure gauges in
the inlet and pressure pipelines, and in the pressurized
auxiliary pipelines.
5.8.2 Safety devices in the inlet, delivery and auxiliary
pipelines
Safety devices in the form of stop valves must be
installed in the pipelines, if not already provided, to
allow the pipelines to be shut off and disconnected
during maintenance and repair work.
5.9 Electrical connections
The power supply cables of the drive motor must be
connected by a trained electrician, according to the
motor manufacturer’s circuit diagram. The valid VDE
regulations, the regulations of the local electricity board
and the operating manual for the motor must be
complied with.
Danger due to electrical power must be excluded and
an EMERGENCY STOP switch in accordance with EN
809 must be provided.
The pump must not run dry, not even for
checking the sense of rotation.
Refer 6.1... Control of drive motor sense of rotation
5.10 Checking the pressure of the system with built–in
pump
If the whole system with built–in pump is to be sub-
jected to a final pressure test, the test pressure must
not be more than the maximum permissible internal
pressure of the pump (see data sheet).

NT
11
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
6 Start–up/Shutdown
6.1 Preparations for (initial) start–up
6.1.1 Filling and bleeding the pump
Prior to starting up, the pump and the suction and inlet
pipeline must be filled with delivery fluid.
During bleeding, the stop valves in the inlet and delivery
pipelines must be open to allow air pockets to escape
into the piping system, and out from there via the
bleeder pipeline.
If the pump fails to build up pressure when started up
(see manometer), bleeding must be repeated.
During bleeding of the pump and the plant, hazardous
or environmentally harmful fluid and gas emerging
must be safely collected and discharged.
6.1.2 Control of drive motor sense of rotation
The sense of rotation of the motor must match the
sense of rotation arrow on the pump. To check the
sense of rotation, the motor can be switched on briefly
when the pump is full.
The pump must not run dry, not even for
checking the sense of rotation.
In the case of pumps with a mechanical seal that is de-
pendent on the sense of rotation, the motor must al-
ways be disconnected in order to check the sense of
rotation.
If the sense of rotation is incorrect, the sense of rotation
of the three phase motor can be reversed by switching
any two phases.
6.1.3 Switching on any additional devices
Before starting up the pump, any additional devices
must be switched on and must have reached the nec-
essary flow rates/temperatures/pressures.
Note: Pay attention to the flow rates/temperatures/
pressures quoted on the order data sheet or in the
manufacturer’s instructions.
External flushing, external blocking, quench
The liquids for external flushing, external blocking
and/or quench must be suitable for mixing with the ma-
terial to be pumped.
6.2 Start–up
6.2.1 General
Before starting, all filling and venting openings must be
completely closed.
6.2.2 Checking the coupling alignment
Prior to starting and after the first run–up of the pump to
operating temperature, the coupling alignment is to be
checked. Readjust, if necessary (please refer to Sec-
tion 5.4 above). The pump shaft must be capable of
being cranked by hand and without any pressure
points.
6.2.3 Starting
To avoid overloading the drive motor, the pump should
be run up only against a closed pressure stop valve dur-
ing starting.
The stop valve in the inlet pipeline must be fully open.
6.2.4 Drive
Switch on the motor.
Refer to the operating instructions of the drive motor
manufacturer.
6.2.5 Minimum rate of flow
Immediately after reaching the operating speed, the
pressure–side stop valve must be opened and the
pump operated up to at least the minimum rate of flow
(see data sheet).
6.2.6 Setting the pump power output values
The pressure–side stop valve must be opened until the
required pump power output values are obtained (see
data sheet).
6.2.7 Temperature
In order to prevent injuries due to burns, at pumping
liquid temperatures higher than 60 protective de-
vices in accordance with EN 809 must be provided on
site.
It must be ensured that the pump housing
is evenly heated. Differences in tempera-
ture between the top and bottom of the pump, as well as
sudden temperature changes, should be avoided.
Temperature changes in the material of more than
50°C per minute are not permissible.
6.2.8 Adjusting the stuffing box (if fitted)
Any increased leakages at the stuffing box in the initial
operating hours are normally eliminated in the course
of the run–in period. If necessary, tighten the hexagonal
nuts on the gland slightly.
A slight leakage must be set at the stuffing
box. This will discharge any frictional heat
occuring at the sealing surface.
6.2.9 Spare pump
A spare pump belonging to the plant must always be
kept ready for operation. For these purposes, the stop
valve on the supply side must be completely open. The
stop valve on the outlet side must be opened to such a
degree that the pump, filled and bleeded, has operating
temperature.
In plants in which impermissible tempera-
ture may arise due to failure of the operat-
ing pump, a standby pump of sufficient output must be
provided.
Two independent energy sources must be provided for
the operating and standby pumps.
6.3 Shutdown
SPressure pipeline
If a non–return valve is installed in the pressure pipe-
line, the stop valve can remain open. Without non–
return valve, the stop valve must be closed.
SDrive
Switch off the motor. Make sure the pump runs down
smoothly and evenly.
SInlet line
Close stop valve in inlet line.

NT
12
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
SAdditional devices
Switch off any additional devices (external flushing,
external sealing, quench).
In the case of double–acting mechan-
ical seals, the pump and system must
be depressurized before switching off the sealing
pressure.
It must be ensured that the pump does not run back-
wards after switching off. Otherwise, the pump may
reach unacceptably high speeds, and shaft seals de-
pendent on the direction of rotation will be severely da-
maged.
6.4 Measures in the event of standstills
Pumped liquid
... Measures in the event of
brief standstill Measures in the event of
prolonged standstill
May solidify
+
has a preservative effect ÀHear or drain puump Drain pump
May solidify
+
does not have a preserva-
tive effect Hear or drain puump Drain and preserve pump
À
Does not solidify
+
has a preservative effect
À
– –
Does not solidify
+
does not have a preserva-
tive effect –Drain and preserve pump
À
ÀSee section 3.3

NT
13
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
7 Maintenance/Repair
7.1 Maintenance
SThe instructions in Section 2, Safety, must be
observed in maintenance and repair work.
SRegular monitoring and maintenance of the pump
and the drive motor are essential for optimum ser-
vice life and safety.
7.1.1 General monitoring
1. The pump must not run dry.
2. The pump must not run in cavitation.
3. The minimum delivery rate must always be main-
tained (see Section 6.2..).
4. The drive motor must not be overloaded.
5. The bearing temperature must not exceed 
6. The shaft seal must have no inadmissible leakage.
7. Changes to the normal operating data may indicate
faults. The causes must be established.
8. Installed standby pumps must be started up once a
week.
7.1.2 Maintenance of components
7.1.2.1 Bearing and lubrication
The nominal service life of the bearing is designed for a
minimum of 2 years continuous operation, in accord-
ance with DIN ISO 281. The actual usable life may be
lower, due to intermittent operation, high temperature,
low viscosity or the like.
The running noises and the temperature in the bearing
area must be checked at regular intervals. We recom-
mend monitoring bearings by means of shock pulse
measurements. If damage to a bearing is detected, the
bearing must be replaced.
The bearing area can become very hot.
Risk of burning if touched!
As a precautionary measure, we recommend that
the groove ball bearing is replaced every 2 years.
7.1.2.2 Shaft seal
The shaft is sealed either by a stuffing box or
mechanical seal.
SStuffing box
Any increased leakages at the stuffing box in the
initial operating hours are normally eliminated in the
course of the run–in period. If necessary, tighten the
hexagonal nuts on the gland slightly.
Ensure that there is slight leakage at the stuffing
box. This will discharge any frictional heat occurring
on the sealing surface.
If the leakage increases excessively, and if it also
cannot be reduced by repeated slight tightening of
the hexagonal nuts, the packing rings have lost their
elasticity of shape and must be replaced.
SMechanical seal
A maximum dripping rate of 10 g/h may occur during
operation and is normal. If the dripping is heavier,
the shaft seal must be replaced.
SAdditional devices
Any additional device at the shaft seal (external
flushing, external sealing, quencher) must be moni-
tored.
A defective shaft seal can cause uncontrolled dis-
charge of pumping liquid.
This constitutes a hazard to people (possibility of
spraying liquid) and to the environment!
7.1.2.3 Coupling
Following initial start–up, after first heating of the pump
to operating temperature and at regular intervals, the
alignment of the coupling and the condition of the flex-
ible elements in the coupling is to be checked (please
refer to Section 5.4 above).
Note: Worn flexible elements are to be replaced.
7.1.2.4 Drive
Refer to the operating instructions of the motor
manufacturer.

NT
14
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
7.2 Repair
General
The system operator is responsible for ensuring that in-
struction in safety is provided. The personnel must be
made aware of all hazards that can arise in connection
with the pumped liquid or the plant.
Mounting and repair work
Trained Service fitters are available on request to carry
out mounting and repair work.
For all repairs, it must be ensured that the pump is de-
pressurised, completely drained and cool. The motor
must be protected against unintended switching on.
We must refuse acceptance of repair work on pumps
filled with fluid, for the protection of our staff and for
environmental reasons. The expenditures for disposal
with respect to the environment are to be carry by the
customer/operating company.
Hazardous substances
Where repairs are to be carried out on pumps which
have been operated with hazardous substances À
and/or environmentally harmful media, the
customer/operator must inform its own personnel on
site, or our personnel where repairs are returned to our
factory or a service workshop, without being
specifically requested to do so.
Together with the request for a Service fitter a
verification of delivery material, for example in the form
of a DIN safety data sheet, must be submitted to us.
Alternatively, you can request a certificate of safety
(form no. 448/191) from our Service department, filling
it out truthfully, correctly and in full. Send the completed
form to the center commissioned with carrying out the
repair, or hand it to our Service fitter.
ÀHazardous substances are:
SToxic substances
SHealth–endangering substances
SCorrosive substances
SIrritants
SExplosive substances
SFire–inducing substances
SHighly flammable, easily flammable and normally
flammable substances
SCarcinogenic substances
SSubstances impairing fertility
SGenetically distorting substances
SSubstances in other ways hazardous to humans
Pumps or units which pump hazardous substances or
substances that are dangerous to the environment
must be completely decontaminated.
7.2.1 Dismounting the centrifugal pump
Before dismounting, the following work must be carried
out:
SElectrical danger must be eliminated! The motor
must be secured against being switched on. If
necessary, the power supply cable must be
disconnected from the motor by an authorized
electrician.
SClose all stop devices in the inlet and delivery pipe-
line, and in the auxiliary pipelines.
SAllow the pump housing to cool to ambient
temperature.
SDrain the fluid in flowable condition from the pump.
Note: Use a collecting tank.
SThe pump must be depressurized and drained.
SHazardous substances and/or environmentally
harmful media must be drained off and collected
such that no danger to life and limb is created.
Environmentally compatible disposal must be
ensured.
SRemove auxiliary pipelines, if fitted.
SDismount manometer lines, manometers and hold-
ing devices.
SDismount protection against accidental contact.
The pump must be dismounted by a qualified
technician using the pertaining drawings.
To prevent damage, it is especially important to ensure
that the components are dismounted concentrically
and that they are not tilted.
Dismounting instructions:
SThe pumps are produced as standard in process de-
sign. This means that the insert unit can be dis-
mounted without the need to remove the volute
housing and the pipes.
SIf a coupling with a distance piece is used, the motor
can remain on the base plate during this process.
SThe fitting position of all components must be accu-
rately marked before dismounting.

NT
15
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
7.2.2 Mounting the centrifugal pump
Before remounting check all parts for wear
and aging and, as necessary, replace with
original replacement parts.
Clean all parts before mounting. Always fit new
gaskets.
The pump must be mounted by a qualified techni-
cian using the pertaining drawings. The prescribed
tightening torque must be observed.
To prevent damage, it is especially important to ensure
that the components are mounted concentrically and
that they are not tilted.
Mounting instructions:
SThe markings applied when dismounting must be
observed. The components must be put back in their
original fitting position.
SWhen assembling, screws and nuts must be painted
with a suitable high–temperature screw paste (e.g.
Molykote P37).
SAfter fitting the insert unit, the pump shaft must lie
exactly flush with the motor shaft.
SAfter tightening the screws, it must be possible to
turn the pump and drive manually without straining
points.
Mounting the rolling bearings
SRolling bearings with guard discs are already filled
with grease and are ready for installation.
SOpen rolling bearings must on principle be provided
with a new permanent grease filling.
Fill with grease
SFill hollow spaces between the rolling bodies up to
approx. 40% with grease.
Bearing bracket
size Rolling bearing
Abbreviation Grease quantity in grams
530
585
700
6410 J C3
6413 J C3
NU 2219 ECJ
ca. 35
ca. 65
ca. 50
SScrape off excess grease (most suitably with your
fingers; do not use metal objects).
Rolling bearing greases
For the lubrication of the groove ball bearing, we
recommend to use the below–listed rolling bearing
greases or equivalent. The order of producers is no
quality ranking.
Producer Brand name Designation
to DIN 51825
Agip Agip GR MU3 K3K–20
ARAL Aralub HL3 K3K–20
BP BP Energrease LS3 K3K–20
ESSO BEACON 3 K3N–30
Fuchs RENOLIT FWA 220 K3N–20
Klüber MICROLUBE GL 263 K3N–20
Mobil–Oil Mobilux 3 K3K–20
Shell Shell Alvania Fett R3 K3N–30
SKF SKF–Fett LGMT3 K3K–30
If none of the listed rolling bearing greases is available,
we recommend in any case a multi–purpose grease on
lithium basis which corresponds to the above DIN
designation.
Grease mixture with grease grades of different basic
oils and thickeners leads to a reduction of the
lubricating properties and must therefore be avoided.
7.2.3 Tightening torque
Note: With poor and lightly greased surfaces, the va-
lues must be increased by 10–15%, in order to reach
the required performance.
Part no. Thread Quality Tightening
torque
[Nm]
901.03 M 16 8.8 150
901.04
901.05 M 12 5.6 35
901.10 M 16 8.8 150
901.13 M 12
M 16 8.8 31 150
902.01 M 16 8.8 150
902.05 M 12 A4–70 44
902.06 M 20 A4–70 204
903.01
903.02
903.03
903.04
903.05
903.06
903.26
G 1/4
G 3/8
G 1/2St 10
15
30
914.01 M 8
M 10
M 12
M 16 8.8 19
35
63
150
914.02 M 12 8.8 63
914.04
914.05 M 6
M 8
M 10 8.8 9
22
35
914.07 M 16 8.8 150
914.10 M 20 8.8 300
922.01
M 12 x 1,5
M 20 x 1,5
M 24 x 1,5
M 30 x 1,5
M 36 x 1,5
M 48 x 1,5
1.4021
20
96
157
279
565
700

NT
16
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
Following the mounting the centrifugal pump, the
following operations are to be performed.
SAlign coupling (please refer to Section 5.4 above).
SAttach protection against accidental contact and
supporting foot, if any.
SAttach auxiliary pipelines.
SAttach manometer pipelines, manometer and hold-
ing devices to the pump.
SElectrical danger must be eliminated! Power supply
cables must only be connected by qualified
electricians. Pay attention to sense of rotation.
Start up pump as per instructions in Section 6.
7.3 Replacement parts
The application guidelines in accordance with DIN 24
296 can be taken as a basis for spare parts stock hold-
ing (see Section 7.3.2).
However, for reasons of operational safety, we recom-
mend the stocking of complete insert units or spare
pumps.
Advantage: In the event of damage, a defective unit
can be replaced by a spare unit without great expendi-
ture and in a very short space of time.
7.3.1 Ordering spare/replacement parts
The following details are required for handling orders
for replacement and spare parts:
SPump abbreviation À
SPump number À
SYear of construction À
SPart number
SDenomination
SQuantity
Àrefer to name plate
7.3.2 Replacement parts for two–year continuous operation as per DIN 24 296
Part No. Part denomination Number of identical pumps (including standby pumps)
2 3 4 5 6 and 7 8 and 9 10 and more
Set/Replacement parts quantity
171.01 Diffuser (all two–stage pump sizes) 1 1 1 2 2 3 30%
210.01
210.02
210.03
À
Shaft or
Shaft or
Shaft with impeller nut 922.01 or
impeller nut 922.02 with
spring washer 934.01 or
spring ring 936.01 or
O–ring 411.10
1 1 2 2 2 3 30%
230.01 Impeller (all single–stage pump sizes) 1 1 1 2 2 3 30%
230.02
230.03
514.01
904.05
Impeller first stage and
Impeller second stage with À
Threaded ring and
Hexagon socket with cup point 1 1 1 2 2 3 30%
321.01
321.02
321.03
321.04
322.01
Groove ball bearing
Groove ball bearing
Groove ball bearing Á
Groove ball bearing
Radial roller bearing
1 1 2 2 3 4 50%
–ÀBearing bracket complete, consisting of:
Shaft, Groove ball bearing, bearing cover etc. – – – – – 1 2
433... Mechanical seal 2 3 4 5 6 7 90%
461.01 Stuffing box packing (set) 4 4 6 6 6 8 40%
502.1
502.2 Wear ring Wear ring 2 2 2 3 3 4 50%
diverse ÀGaskets for pump casing (set)
Other gaskets (set) 4 6 8 8 9 12 150%
ÀCan be purchased as assembly group/sale group.
ÁDepending on bearing bracket size.

NT
17
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
8 Operating Faults, Causes and Remedial Action
8.1 Faults with reference number for cause and remedial action
The table below is intended as a guide to identifying faults and their possible causes.
If faults occur which are not listed here, or which cannot be traced back to the listed causes, we recommend consulting the
factory, or one of our branch offices or sales offices.
The pump must be depressurized and drained when faults are being rectified.
Centrifugal pump faults Reference numbers for cause and remedial action
Delivery rate too low 1, 2, 3, 4, 5, 6, 7, 8, 9, 21, 22
Delivery head too low 2, 3, 4, 5, 6, 7, 8, 9, 21, 22
Power consumption of pump too high 9, 11, 12, 16, 17, 21, 22, 25
Delivery pressure too high 9, 12
Bearing temperature increased 16, 17, 18, 20, 25
Pump housing leaky 23
Heavy leakage of shaft seal 10, 13, 15, 16, 17, 27
Pump not operating smoothly 1, 2, 3, 4, 5, 6, 8, 11, 16, 17, 24, 25, 26
Pump gets hot 2, 5, 26
8.2 Causes and remedial action
Ref. no.: Cause Remedial action
1Delivery head higher than nominal delivery head
of pump. 1. Open stop valve in pressure pipeline until operating point is reached.
2. Install impeller with larger diameter.
3. Increase rotation speed (turbine, frequenzy control, ...). À
2Pump or pipelines not properly bled or filled. Bleed and top up pump or pipelines.
3Inlet pipeline or impeller blocked. Clean pipelines and impeller.
4Air pockets forming in pipeline. Perhaps install a vent valve, or lay pipeline differently.
5 NPSHplant (inlet) too low. 1. Check fluid level in inlet tank.
2. Open stop valve in inlet pipeline fully.
3. Lay inlet pipeline differently if friction losses are too high.
4. Check filter in inlet pipeline, if fitted.
5. Check inlet flow conditions of pump.
6Wrong direction of rotation of pump. Reverse polarity of any two phases on motor.
7Rotation speed too low. Increase rotation speed (turbine, frequenzy control, ...). À
8Excessive wear on inner pump parts. Replace worn parts.
9Density or viscosity of delivery medium does not
comply with pump design data. Consult the factory in the event of faults due to non–compliance with design data. À
10 Shaft sleeve damaged. Mount new shaft sleeve.
11 Delivery head lower than nominal delivery head
of pump. 1. Regulate operating point with stop valve in pressure pipeline. 2. Turn off impeller in event of continuous overload.
12 Rotation speed too high. Reduce rotation speed (turbine, frequenzy control, ...). À
13 Shaft seal damaged. Check shaft seal parts for wear and replace if necessary.
14 – –
15 Packing material unsuitable for the delivery me-
dium.
Gland is askew, or too loosely tightened.
1. Wrong packing material used. Repack pump with suitable
material.
2. Tighten gland evenly.
16 Pump aggregate wrongly aligned. Re–align pump as described.

NT
18
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
17 Pump twisted. Check pipelines for twists in connections.
18 Excessive axial thrust. Clean relief bore holes in impeller.
19 – –
20 Specified coupling half gap not complied with. Set coupling half gap as per installation diagram.
21 Motor voltage incorrect. Use motor with correct voltage.
22 Motor runs only to two phases. 1. Check cable connection.
2. Replace fuses.
23 Screws not tight. 1. Tighten screws.
2. Replace gaskets.
24 Impeller out–of–true. 1. Clean impeller.
2. Re–balance impeller.
25 Groove ball bearing defective. Replace groove ball bearing.
26 Delivery rate below minimum. Increase delivery rate to minimum.
27 Pumped liquid corroding mechanical seal mate-
rial. Check pumped liquid (e.g.: incorrect temperature, concentra- tion, dosing of additives, etc.)
ÀConsult factory

NT
19
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
9 Associated Documentation
Shaft seal: Stuffing box with internal sealing
Abbreviation: U1B
Sectional drawing –Series NT
Sizes at bearing bracket size 360, 470 and 530
Mechanical seal unbalanced
U3...D oder U3...K
U3...K only with bearing bracket size 360
Mechanical seal
unbalanced
U8F
Mechanical seal
unbalanced
U3.9D, U3.12D
Mechanical seal
balanced
U2...D
Stuffing box with
external sealing
U1C
Design with intermediate ring
Design of the bearing and
impeller protection with
bearing bracket size 530
Bore only with
U3...K

NT
20
VM 460.0002 GB/07.00 –Ident–Nr. 550 088
Sectional drawing –Series NT
Two–stage sizes at bearing bracket size 360
Mechanical seal unbalanced
U3...D
Mechanical seal unbalanced
U8F
Casing cover design with pump size
2/40–250 and 2/50–250
Denomination Part No.
–––––––––––––––––––––––––––––––––––––
Volute casing 102.01
Stage casing 108.01
Casing cover 161.01
Casing cover 161.03
Casing cover 161.01
Casing cover 161.06
Casing cover 161.08
Casing cover 161.09
Casing cover 161.10
Casing cover 161.11
Casing cover 161.12
Diffuser 171.01
Supporting foot 183.01
Shaft 210.01
Shaft 210.02
Shaft 210.04
Impeller 230.01
Impeller first stage 230.02
Impeller second stage 230.03
Groove ball bearing 321.01
Groove ball bearing 321.02
Groove ball bearing 321.03
Groove ball bearing 321.04
Bearing bracket 330.01
Bearing cover 360.01
Bearing cover 360.02
Gasket 400.01
Gasket 400.02
Joint ring 411.01
Joint ring 411.02
Joint ring 411.04
Joint ring 411.07
Mechanical seal 433.01
Mechanical seal 433.04
Mechanical seal 433.05
Mechanical seal 433.06
Gland 452.01
Lantern ring 458.01
Stuffing box packing 461.01
Thrower 507.01
Denomination Part No.
–––––––––––––––––––––––––––––––––––––
Intermediate ring 509.01
Threaded ring 514.01
Nilos ring 516.01
Nilos ring 516.02
Shaft sleeve 523.02
Spacer sleeve 525.01
Clamping sleeve 531.01
Distance washer 551.01
Compensating disc 557.01
Rivet 565.01
Pipeline 700.01
Pipe 710.02
Pipe union 730.01
Threaded pipe union 731.04
Threaded pipe union 731.05
Threaded pipe union 731.06
Threaded pipe union 731.07
Hexagon screw 901.13
Stud bolt 902.03
Screw plug 903.01
Screw plug 903.02
Screw plug 903.04
Screw plug 903.07
Grub screw 904.01
Grub screw 904.02
Grub screw 904.04
Socket–head cap screw 914.01
Socket–head cap screw 914.02
Socket–head cap screw 914.04
Socket–head cap screw 914.05
Nut 920.03
Impeller nut 922.01
Circlip 932.10
Spring washer 934.01
Spring ring 936.01
Key 940.01
Key 940.02
Key 940.03
Name plate 971.01
Connections
––––––––––––––––––––––––
BI External sealing
FD Draining
FF Filling
LO Leakage outlet
PM2 Pressure measuring
device