Desmi MVA Series Troubleshooting guide

OPERATION AND MAINTENANCE INSTRUCTIONS
Vertical Multistage Centrifugal Pump
Series: MVA, MVS
DESMI Pumping Technology A/S
Tagholm l, DK-9400 Nørresundby, Denmark
Tel.:
[phone]
Fax:
[phone]
E-mail:
[email protected]
Internet:
www.desmi.com
Manual:
T1536
Language:
English
Revision:
A1(03/20)

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DESMI Pumping Technology A/S 2
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Table of Contents
1. NOTES..........................................................................................................................................................4
1.1 PREFACE ....................................................................................................................................................... 4
1.2 ICONS AND SYMBOLS ...................................................................................................................................4
2. WARRANTY..................................................................................................................................................4
2.1 WARRANTY CLAUSES....................................................................................................................................4
3. PRODUCT .....................................................................................................................................................5
3.1 PRODUCT INTRODUCTION ...........................................................................................................................5
3.2 MODEL DESCRIPTION ...................................................................................................................................5
3.3 MECHANICAL SEAL CODE .............................................................................................................................5
3.4 RATED CURRENT........................................................................................................................................... 6
4. SAFETY AND ENVIRONMENT........................................................................................................................6
4.1 GENERAL ......................................................................................................................................................6
4.2 USER.............................................................................................................................................................6
4.3 SAFETY MEASURES .......................................................................................................................................7
4.4 SAFETY PROTECTION MEASURES .................................................................................................................7
4.5 ENVIRONMENTAL ASPECTS..........................................................................................................................8
5. PURPOSE AND APPLICATION SCOPE ............................................................................................................8
5.1 PRODUCT FESTURES.....................................................................................................................................8
5.2 PURPOSE ......................................................................................................................................................8
5.3 APPLICATION SCOPE.....................................................................................................................................8
5.4 WORKING MEDIUM......................................................................................................................................8
6. TECHNICAL PARAMETERS.............................................................................................................................9
6.1 AMBIENT TEMPERATURE .............................................................................................................................9
6.2 LIQUID TEMPERATURE ................................................................................................................................. 9
6.3 CACULATION METHOD FOR MINIMUM INLET PRESSURE ............................................................................9
6.4 PRESSURE AND TEMPERATURE ..................................................................................................................10
6.5 ELECTRICAL PARAMETERS..........................................................................................................................10
6.6 MOTOR STARTUP/SHUTDOWN TIMES .......................................................................................................10
6.7 SIZE AND WEIGHT.......................................................................................................................................10
6.8 NOISE LEVEL ............................................................................................................................................... 10
7. PRECAUTIONS BEFORE INSTALLATION AND OPERATION ...........................................................................11
7.1 PLEASE OPERATE AS FOLLWS DURING INSTALLATION TO AVOID PUMP DAMAGE .................................... 11
7.2 CHECK BEFORE PUMP STARTUP .................................................................................................................12
7.3 STARTUP STEPS .......................................................................................................................................... 13
8. PERFORMANCE PARAMETERS....................................................................................................................14
9. MAINTENANCE ..........................................................................................................................................15
10. TRANSPORTATION AND STORAGE ...........................................................................................................16
10.1 TRANSPORTATION ...................................................................................................................................16
10.2 STORAGE ..................................................................................................................................................16
11. TROUBLE SHOOTING................................................................................................................................16
12. SIZE DIAGRAMS........................................................................................................................................18

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DESMI Pumping Technology A/S 3
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13. EXPLODED VIEWS.....................................................................................................................................27

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DESMI Pumping Technology A/S 4
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1. NOTES
1.1 PREFACE
This manual contains important information for correct, reliable and effective operation and
product application. Compliance with the operational instructions is crucial to assurance of
product reliability, longer service life and avoidance of any risk. This chapter contains
information about this manual and general safety. The following chapters provide information
about normal operation, installation, maintenance and repair of products.
•Familiar with contents of the manual;
•Accurately abide by instructions and notes;
•Comply with the manual and never change the sequence required by operations;
•Put this manual or its duplicate copy at a fixed position near the product so that all
operators can use it.
1.2 ICONS AND SYMBOLS
The following icons and symbols are used in this manual and all relevant documents.
Warning
Dangerous voltage: Comply with safety symbols of IEC 417 - 5036.
Warning
Operation or procedure: If you operate carelessly, it may cause personal injury or
product damage. General hazard symbols comply with ISO7000 -0434.
Caution
Used to introduce safety instructions. Inobservance may result in product damage
or dysfunction.
Environmental instructions
The product complies with environmental instructions.
2. WARRANTY
2.1 WARRANTY CLAUSES
The warranty period depends on your contract clauses or at least general clauses and
conditions for sales.
Caution
Change to products can be made only after communication with and permit by the
manufacturer. The original spare parts and fittings authorized by the manufacturer shall be
used so as to assure safety. Utilization of other unauthorized parts and components shall
exempt the manufacturer from any liability for relevant damage.
Caution
Any warranty for product reliability and safety is effective only when the user
complies with this manual and uses products correctly. In no cases, shall the extent stated in
the data sheets shall be exceeded.
In case that one or more of the following problems occur, this warranty becomes invalid:

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•The buyer makes any change by himself.
•The buyer repairs the product by himself or asks a third party to repair it.
•The product is treated or maintained improperly.
•Non-original pump parts are installed on this product.
Defects to be rectified during the warranty period:
•Defects caused by design, material or manufacturing.
•They are reported during the warranty period.
Other warranty clauses included in general delivery clauses may be provided upon request.
3. PRODUCT
3.1 PRODUCT INTRODUCTION
MVA, MVS are vertical multistage series centrifugal pumps. They are characterized by low
noise, high efficiency, compact structure, small volume and light weight, nice looking,
convenient operation and maintenance, and specifically designed for conveying the cleaning
medium. Pump suction and discharge connection is via flange or thread so that the pump can
be installed easily. The pump is driven by motor and all pressure-bearing components are
made of stainless steel or cast iron.
3.2 MODEL DESCRIPTION
MVA3-10-S-A
MV
A
3
-10
-S
-A
Sign
MV
Product ID, high-efficiency vertical multistage centrifugal pump
series
Material code
A
Machine base and pump cover are made of cast iron
Parameter
3
Rated flow (m3/h)
10
Pump stage quantity
Connection
-S
The stainless steel is AISI316 (AISI304 not indicated)
-A
Pipe connection codes: A-Oval flange; B-Thread; K-Quick
connection; DIN flange not indicated
MVS200-3-C-D
MV
S
200
-3
-C
-D
Sign
MV
Product ID, high-efficiency vertical multistage centrifugal pump
series
Material code
S
All flow passage components are made of stainless steel
Parameter
200
Rated flow (m3/h)
-3
Pump stage quantity
Connection
-C
One small impeller C
-D
One small impeller D
3.3 MECHANICAL SEAL CODE
Materials of mechanical seal
Description
Material
Symbol
Notes
Dynamic ring
configuration
Silicon carbide
Hard alloy
SiC
TuC
Normally configured silicon carbide
Hard alloy is optional

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Static ring
configuration
Graphite
Silicon carbide
Hard alloy
C
SiC
TuC
Normally configured graphite, silicon
carbide
Hard alloy is optional
Rubber configuration
NBR
EPDM
Fluororubber
NBR
EPDM
FPM
Normally configured EPDM
Others are optional
Spring
CrNiMo stainless steel
CrNiMo
-
Other metal parts
CrNiMo stainless steel
CrNiMo
-
3.4 RATED CURRENT
The allowed nominal current of motor for pump configuration is indicated on the motor
nameplate. This shows the nominal working scope of motor and can be used to protect the
motor.
Warning
When using, you must protect not only the motor but also the pump.
4. SAFETY AND ENVIRONMENT
4.1 GENERAL
MVA, MVS vertical multistage centrifugal pumps are developed with the most advanced
technology. It is carefully manufactured and subject to continuous quality control. DESMI
assumes no liability for any damage and injury caused by failure to comply with operational
instructions described in this manual or by negligence during product installation, operation
and maintenance. Failure tocomply with safety instructionsmay endanger safety of personnel,
environment and product itself, and will also result in forfeiture of right to claim compensation
for damage.
Non-compliance will result in the following situations:
•Loss of important pump system functions
•Failure of specified maintenance and repair methods
•Injury to people caused by electrical, mechanical and chemical effects
•Danger to the environment caused by leakage of harmful substances
•Explosion
Depending on activities, additional safety measures may be required. In case of any potential
danger during operation, please contact DESMI.
Caution
The product owner is obliged to abide by local safety regulations and the user’s
internal company guidelines.
Caution
Abide by not only general safety instructions in this chapter but also those under
specific titles.
4.2 USER
All personnel engaged in product operation, maintenance, inspection and installation must
be completely qualified to perform relevant operations, and clearly understand their own
duties and authorized operations all the time. If any relevant person has not mastered
necessary expertise, he/she must be given proper training and guidance. If necessary, the

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service provider may entrust the manufacturer/supplier to organize relevant trainings.
Besides, operators shall ensure that the responsible persons have completely understood
the operating instructions.
4.3 SAFETY MEASURES
This product is well designed. Original parts and fittings comply with safety rules. Any
structural modification or utilization of non-original components may bring safety risks.
Caution
Make sure that the product is running within its working scope. Only in this way can
the product performances be guaranteed.
4.3.1 PRODUCT LABEL
Icons, warnings and notes for products form a part of safety rules. Labels shall not be
removed or covered, and shall be kept clear during the whole life cycle of the product.
Please replace any damaged label immediately.
4.4 SAFETY PROTECTION MEASURES
4.4.1 DURING NORMAL OPERATION
•Please contact the local power supply company in case of any power supply problem.
•Please do not directly touch the covered part of the product since it will produce heat.
•Before the pump is put into use, an undeformed coupling protection cover shall be
always used to protect the coupling, so that the protective plate of coupling will not touch
the rotating coupling.
•The connection box of motor shall be always closed.
4.4.2 DURING INSTALLATION, OPERATION AND MAINTENANCE
Only the authorized personnel can install, maintain and check products, and repair electrical
components. Abide by the local safety rules.
Warning
Before installation, maintenance and repair, be sure to shut off the product power
supply safely.
Warning
The pump surface may be hot after continuous running.
Warning
When starting the pump, make sure that nobody can come close to the rotating
component.
Warning
Carefully operate the pump filled with dangerous liquid. Avoid any danger to
persons or the environment when repairing water leakage, draining water and discharging
air. It is strongly suggested that an air leakage pan shall be placed under the pump.
Warning
Once work is done, immediately re-install and/or re-start all safety-related protective
devices.

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Warning
Before the product is put into operation, please abide by all notes stated in
“Precautions before installation and operation”.
4.5 ENVIRONMENTAL ASPECTS
4.5.1 GENERAL
This product is always friendly to the environment throughout its life cycle. Therefore, if
applicable, biodegradable lubricant shall be used for maintenance.
Environmental instructions
Always comply with the laws, regulations and instructions relevant to health, safety
and environment.
4.5.2 DISMANTLING
The Owner is obliged to dismantle and environmentally dispose of the product.
Environmental instructions
Consult the local government regarding reuse of waste materials or environment-
friendly disposal.
5. PURPOSE AND APPLICATION SCOPE
5.1PRODUCT FESTURES
Low noise, high efficiency, compact structure, small volume and light weight, nice looking,
resistant to mild corrosion, high sealing reliability, convenient operation and maintenance,
etc.
5.2 PURPOSE
•Boiler water supply & condensate system
•Water treatment, permeation and filtration system
•Food, beverage industry
•Water supply & drainage of high-rise buildings
•Agriculture, nursery, golf course irrigation
•Fire protection system
•Industrial cleaning system
•Liquid conveying, circulation and lifting
5.3 APPLICATION SCOPE
•Medium temperature: -20°C ~ +120°C
•Flow range: 0.7~240m3/h
•Max pressure: 33bar
•Medium PH: 3 - 9
•Highest ambient temperature: +40°C (please refer to 6.1 or consult DESMI)
•Max altitude: <=1000m (please refer to 6.1 or consult DESMI)
5.4 WORKING MEDIUM
A thin, nonflammable and non-explosive liquid, contains no solid particles or fiber. The liquid
causes no chemical corrosion to pump materials.
If the density or viscosity of the conveyed liquid is greater than that of water, the motor with
high power shall be considered.

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If all flow passage components required by the system are made of high-grade stainless
steel, a special material is needed.
6. TECHNICAL PARAMETERS
6.1 AMBIENT TEMPERATURE
The product runs in the environment with a max temperature of +40°C. In case that ambient
temperature exceeds +40°C or the motor is installed above 1,000m altitude, the motor rated
output power (P2) will decrease due to the poor motor cooling effect caused by low air
density, as shown in Chart 1. In this case, a motor with higher output power shall be used.
Relationship between motor output power (P2) and ambient temperature
6.2 LIQUID TEMPERATURE
The following chart shows the relationship between liquid temperature and maximum
allowable working pressure.
Note: The maximum allowable working pressure and liquid temperature range are based on
the pump’s own bearing capacity.
6.3CACULATION METHOD FOR MINIMUM INLET PRESSURE
Minimum inlet pressure “H” (unit: meter water column) is calculated as below: H=Pb x 10.2 -
NPSH - Hf - Hv - Hs
Pb = Atmospheric pressure, in unit bar (atmospheric pressure regarded as 1bar), Pb in a
closed system means the system pressure (unit: bar).
NPSH = Net positive suction head, in unit m (taken from NPSH performance curve).
Hf = Friction loss in pipeline at the suction side (in unit m)
Hv = Vaporization pressure (in unit m)
Hs = Safety margin, take 0.5 at least
If the result of calculated H is positive, it means the suction height at the suction side equals
to “H”m. If the result is negative, at least positive Hm pressure is required at the inlet to avoid

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cavitation.
6.4 PRESSURE AND TEMPERATURE
6.5ELECTRICAL PARAMETERS
Refer to the motor nameplate.
6.6MOTOR STARTUP/SHUTDOWN TIMES
Less than 4kW (inclusive): Max 100 times/hour
More than 5.5kW (inclusive): Max 20 times/hour
6.7SIZE AND WEIGHT
As for size, refer to size diagrams of all models
As for weight, refer to package labels
6.8NOISE LEVEL
Electric pump noise
Fig. 2

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7. PRECAUTIONS BEFORE INSTALLATION AND OPERATION
7.1 PLEASE OPERATE AS FOLLWS DURING INSTALLATION TO AVOID PUMP DAMAGE
No.
Diagram
Information
1
The arrow on the pump base plate indicates
the direction of liquid going through the
pump.
2
This information is indicated in Chapter 12
(size diagrams):
• End-to-end length
• Base plate size
• Pipe connection
• Diameter and location of foot bolt
3
The pump can be installed vertically or
horizontally. However, the motor shall be
installed neither below the horizontal plane
nor upside down. Make sure that the motor
cooling fan provides sufficient cool air
circulation. It is suggested that supports shall
be added to a motor above 4KW.
3A
Additional support. Since the pump center is
relatively high, we suggest that one
additional support bracket is provided for
the pump installed on the boat, in an area
with earthquake danger or in the movable
system. The bracket can be installed on
motor base, ship wall, building rigid wall or
rigid component.
4
In order to minimize any noise made by the
pump, we suggest that you install expansion
joints at both sides of the pump.
Install isolating valves at both ends of the
pump so as to avoid system discharge when
it is necessary for pump cleaning,
maintenance and replacement. Use a check
valve to prevent backflow of medium and to
protect the pump.
5
Install pipes to avoid air lock, especially at
the inlet side of the pump.

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6
If your installation is characterized by one of
following features, please install one vacuum
valve near the pump.
●The discharge pipe is sloped downwards
in the direction of leaving the pump.
●Siphonage may occur.
●It is necessary to stop backflow of unclean
water.
Please carefully read warning signs on the pump motor base before startup.
Caution: Do not start the pump before water is filled and air is discharged. In case of dry running,
pump bearing and shaft seal will be damaged. When discharging air, pay attention that water
drained shall not injure people or damage objects, especially avoid scalding by sprayed hot water
when it is used to convey hot water.
Electrical connection
The motor shall be provided with reliable earthing.
Before dismantling the motor connection box or the pump, make sure that the power supply is
disconnected.
One-phase motor is provided with a heat protector inside while three-phase motor shall be provided
with a three-phase protector before installation.
7.2 CHECK BEFORE PUMP STARTUP
• Check if foot bolts are tightened.
• If the pump is full of water or not.
• If the voltage of power grid is correct or not.
• If the rotating direction is correct or not.
• If all pipes are tightly connected or not, if pipes can
• provide water normally or not.
• If valves on inlet pipes are completely opened or not. The outlet valve shall be opened
slowly after the pump is started up.
• Check working pressure if a pressure meter is installed.
• All controls required by normal running.
If the pump is controlled by the pressure switch, check, adjust, start and disconnect the
pressure. Check if the full-load current of the motor exceeds the maximum allowable current
via the pressure switch.
Please carefully read warning signs on the pump
motor base before startup.
Caution
Do not start the pump before water is filled and air is discharged. In case of dry
running, pump bearing and shaft seal will be damaged. When discharging air, pay
attention that water drained shall not injure people or damage objects, especially avoid
damage to materials at the outlet caused by the liquid flowing at a high speed when it is
used to convey hot water.

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7.3 STARTUP STEPS
1. Open the inlet valve and close the outlet valve.
2. Screw off the water injection plug and start filling water
3. Check rotating direction of the motor
4. Start up the motor
5. Loosen the discharge valve and slowly open the outlet valve
Fig. 5
Lock nut
Drain valve

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6. Adjust the outlet valve to the required pressure
7. Tighten the discharge valve
8. If you have any question, please read the instructions or call DESMI.
8. PERFORMANCE PARAMETERS
Model
Flow M3/h 50Hz
Minimum flow
Maximum flow
Rated flow
1
0.7
2.4
1
2
1.0
3.5
2
3
1.2
4.5
3
4
1.5
8
4
5
2.5
8.5
5
10
5
13
10
15
8
23
15

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20
10.5
29
20
32
15
40
32
45
22
58
45
64
30
85
64
90
45
120
90
120
60
150
120
150
80
180
150
200
100
240
200
The pump may run with 60hz motor. The flow, head and power of the pump running at 60hz
will be changed. As for running at 60hz, please consult DESMI.
9. MAINTENANCE
Before maintenance, confirm that the pump is shut off so as to avoid accident. Pump bearing and
shaft seal require no maintenance.
Motor bearing
The motor without a nozzle requires no maintenance. The motor with a nozzle (including
motor above 11kW) shall be lubricated with lubricant or similar high-temperature lithium base
grease. For more details, refer to instructions on the windscreen. In case of seasonal
running (motor shutdown for over 6 months), lubricate before starting the motor.
The pump installed as per this manual will work effectively without much maintenance.
The mechanical seal is adjusted automatically. The contact surface of dynamic ring and
static ring in the seal will be lubricated and cooled down by the liquid conveyed by the pump.
The sliding bearing in the pump will be lubricated by the liquid conveyed by the pump.
If the pump is installed at a place where it is likely to freeze, proper quantity of antifreezing agent
must be added so as to avoid damage to the pump due to freezing of the liquid conveyed by the
pump.
If the pump is out of service during a frost period, you should drain the liquid inside it so as to
avoid any damage to the pump. The liquid inside the pump may be drained via the water
injection hole at the pump head and the drainage hole at bottom. Pay attention to safety of
persons and objects during water drainage (cold or hot). When using the pump once again,
firstly tighten the vent plug and drainage valve. When it is necessary to replace the drainage
valve, you must loosen the bypass valve, then unscrew the drain plug (refer to Fig. 5). If you
want to install the drainage valve, firstly tighten the drain plug, then tighten the bypass valve.

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10.TRANSPORTATION AND STORAGE
10.1 TRANSPORTATION
1. Transport the pump to the tray or the position specified on
the package.
2. Make sure that the pump is stable.
3. If any, please follow the instructions on the package.
Warning
The pump must be lifted as per the current lifting
guideline. Only qualified personnel are allowed to lift the
pump.
Warning
Do not lift the pump with the frequency converter (if
provided with a frequency converter), electric appliance parts
or motor cover. Make sure that the pump keeps balanced
when it is lifted.
Warning
The pump may be inclined when it is lifted. Before
correct placement and installation, do not dismantle the lifting
device on the pump.
Warning
All pump motors are provided with lifting-eye bolts. If such bolts cannot
withstand the weight of the whole pump, the water pump with a standard motor
shall be lifted at the pump head via steel belts or in a similar method.
10.2 STORAGE
It is suggested that ethylene glycol is filled into the pump chamber during pump storage so
as to avoid frost.
Storage
Ambient temperature (°C)
-10 / +40
Maximum humidity
Less than 80% and no condensation
occurs to the pump at 20°C
11. TROUBLE SHOOTING

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Warning
Before installation, maintenance or restoration, please abide by general safety
measures.
Problem description
Possible reason
Solution
Check point
Leakage along the
shaft
Running surface of the
mechanical seal is
damaged
Replace the mechanical
seal
Check dust/grinding part
of the pump
New pump: The
mechanical seal is
blocked during assembling
When the pump is running,
rapidly open and close the
outlet valve
The mechanical seal is
installed incorrectly
Install the mechanical seal
correctly, use water and
soap as a lubricant during
installation
The elastomer is damaged
due to impact of the
medium
Choose correct
mechanical seal elastomer
The pressure is too high
Use mechanical seal of
correct type and pressure
range
The shaft is worn
Replace the shaft and
mechanical seal
The pump runs without
water, it is a dry running
Replace the mechanical
seal
Leakage at pump
bracket top or pump
bottom
The O-ring is damaged
Replace the O-ring
The O-ring does not
withstand the pumping
medium
Replace with an O-ring
suitable for the pumping
medium
The pump is deformed due
to too much stress at the
pump foot
Reduce the pressure on
the pipe
There is no pressure when
installing the pump foot
The pump and the pipeline
connecting part are
supported additionally
Pump vibration and
noise
The coupling is installed
incorrectly
Check and re-install the
coupling
There is no medium in the
pump
Fill the pump and
discharge air
There is no medium input
Make sure that there is
sufficient medium at the
inlet
The pump bearing or
motor bearing is damaged
Replace the bearing
There is very little usable
NPSH, and the pump has
suffered cavitation
Increase pressure at the
inlet
The pump fails to run
within the specified
operating range
Choose other pumps
Adjust the system so that
the pump runs within the
specified range
The pump is installed on
an uneven surface
Adjust installation

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Pump malfunction
The pump interior is
blocked
Check the pump interior
Pump startup failure
No power
Check the power supply
●Current
●Main switch
●Fuse
Check the safety setting of
the motor
●Leakage switch
●Heat protection switch
The heat protection switch
of the motor is triggered
The heat protection switch
of the motor. If this
problem often occurs,
please contact the
supplier.
Check if the set value is
correct
Motor started but pump
failure to work
The coupling between the
pump and the motor is
loose
Check and tighten the
coupling bolt
The pump shaft is
damaged
Contact the manufacturer
to replace it
Insufficient flow or/and
pressure of pump
The outlet or inlet valve is
closed
Open the valve
There is air in the pump
Discharge air in the pump
Pressure at the pump
suction end is low
Increase pressure at the
pump suction end
The pump rotating
direction is wrong
Replace two phases of
three-phase wiring
There is no air discharge
in the suction pipe
Discharge air in the
suction pipe.
There is air leakage at the
suction end
Check the air leakage
position.
Water flow is very low, the
bubble pump is blocked
Make sure that flow is
increased or a smaller
pump is used
The diameter of suction
pipe is small
Increase the pipe diameter
The bottom valve is
blocked
Clean the bottom valve
The impeller or pump
chamber is blocked
Clean the pump interior
The O-ring of the diffuser
is damaged
Replace the O-ring
The O-ring is not suitable
for the pumping medium
Replace with an O-ring
suitable for the pumping
medium.
12. SIZE DIAGRAMS

_______________________________________________________________________________
DESMI Pumping Technology A/S 19
www.desmi.com
Tagholm 1
9400 Nørresundby –Denmark
Tel: [phone] Fax: [phone]
E-mail: [email protected]
Sizes of Models MVA2, MVS2
Pump
model
Size
Oval flange
(MVA)
DIN flange
(MVS)
B1
B1+B2
B1
B1+B2
D1
D2
2-2
220
440
245
465
140
110
2-3
238
458
263
483
140
110
2-4
256
476
281
501
140
110
2-5
274
494
299
519
140
110
2-6
297
547
322
572
160
125
2-7
315
565
340
590
160
125
2-8
333
583
358
608
160
125
2-9
351
601
376
626
160
125
2-10
269
619
394
644
160
125
2-11
384
637
412
662
160
125
2-12
422
712
447
737
180
125
2-13
440
730
465
755
180
125
2-14
458
748
483
773
180
125
2-15
476
766
501
791
180
125
2-16
494
784
519
809
180
125
2-17
512
802
537
827
180
125
2-18
530
820
555
845
180
125
2-19
548
838
573
863
180
125
2-20
566
856
591
881
180
125
2-21
584
874
609
899
180
125
2-22
602
892
627
917
180
125
2-23
628
958
653
983
190
140
2-24
646
976
671
1001
190
140
2-25
664
994
689
1019
190
140
2-26
682
1012
707
1037
190
140
DIN flange (MVS)/F
Oval flange (MVA)/A
Threaded connection (MVS)/G Anulated connection (MVS)/K
Threaded connection (MVS)/G Anulated connection (MVS)/K
Oval flange (MVA)/A
DIN flange (MVS)/F
Sizes of Models MVA1, MVS1
Pump
model
Size
Oval flange
(MVA)
DIN flange
(MVS)
B1
B1+B2
B1
B1+B2
D1
D2
1--2
238
468
264
494
136
109
1--3
256
486
282
512
136
109
1--4
274
504
300
530
136
109
1--5
292
522
318
548
136
109
1--6
310
540
336
566
136
109
1--7
328
558
354
584
136
109
1--8
346
576
372
602
136
109
1--9
364
594
390
620
136
109
1--10
382
612
408
638
136
109
1--11
400
630
426
656
136
109
1--12
422
672
448
698
155
124
1--13
440
690
466
716
155
124
1--15
476
726
502
752
155
124
1--17
512
762
538
788
155
124
1--19
548
798
574
824
155
124
1--21
584
834
610
860
155
124
1--23
620
870
646
896
155
124
1--25
672
982
698
1008
175
137
1--27
708
1018
734
1044
175
137
1--30
762
1072
788
1098
175
137
1--33
816
1126
842
1152
175
137
1--36
870
1180
896
1206
175
137

_______________________________________________________________________________
DESMI Pumping Technology A/S 20
www.desmi.com
Tagholm 1
9400 Nørresundby –Denmark
Tel: [phone] Fax: [phone]
E-mail: [email protected]
Sizes of Models MVA3, MVS3
Pump
model
Size
Oval flange
(MVA)
DIN flange
(MVS)
B1
B1+B2
B1
B1+B2
D1
D2
3--2
238
468
264
494
136
109
3--3
256
486
282
512
136
109
3--4
274
504
300
530
136
109
3--5
292
522
318
548
136
109
3--6
310
540
336
566
136
109
3--7
328
558
354
584
136
109
3--8
350
600
376
626
155
124
3--9
368
618
394
644
155
124
3--10
386
636
412
662
155
124
3--11
404
654
430
680
155
124
3--12
422
672
448
698
155
124
3--13
440
690
466
716
155
124
3--15
476
726
502
752
155
124
3--17
528
838
554
864
175
137
3--19
564
874
590
900
175
137
3--21
600
910
626
936
175
137
3--23
636
946
662
972
175
137
3--25
672
982
698
1008
175
137
3--27
708
1018
734
1044
175
137
3--29
744
1054
770
1080
175
137
3--31
784
1114
810
1140
195
151
3--33
820
1150
846
1176
195
151
3--36
874
1204
900
1230
195
151
Sizes of Models MVA4, MVS4
Pump
model
Size
Oval flange
(MVA)
DIN flange
(MVS)
B1
B1+B2
B1
B1+B2
D1
D2
4-2
238
458
263
483
140
110
4-3
265
485
290
510
140
110
4-4
297
547
322
572
160
125
4-5
324
574
349
599
160
125
4-6
351
601
376
626
160
125
4-7
395
685
420
710
180
125
4-8
422
712
447
737
180
125
4-9
449
739
474
764
180
125
4-10
476
766
501
791
180
125
4-11
503
793
528
818
180
125
4-12
530
820
555
845
180
125
4-13
565
895
590
920
190
140
4-14
592
922
617
947
190
140
4-15
619
949
644
974
190
140
4-16
646
976
671
1001
190
140
4-17
673
1003
698
1028
220
150
4-18
700
1030
725
1055
220
150
4-19
727
1057
752
1085
220
150
4-20
754
1084
779
1109
220
150
4-21
781
1111
806
1136
220
150
4-22
808
1138
833
1163
220
150
Threaded connection (MVS)/G Anulated connection (MVS)/K
DIN flange (MVS)/F
DIN flange (MVS)/F
Oval flange (MVA)/A
Oval flange (MVA)/A
Threaded connection (MVS)/G Anulated connection (MVS)/K