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InnovationInnovation

A completely new concept of a magnetic-drive pump

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Subdivision of the presentationSubdivision of the presentation

1.) Weakness of the magnetic-drive pumps in classical design in cases of intermittent flow (quasi-dry running)

2.) New concept to locate the radial slide bearings*

3.) New concept of a close coupled pump*

4.) New concept to absorb the axial thrust by the magnetic coupling itself*

5.) Photo of the magnetic-drive pump type MONSUN * applied for patents

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Intermittent flow and its Intermittent flow and its consequencesconsequences

The intermittent flow is one of the most frequent and gravest cause for breakdowns of centrifugal pumps.

Losses at the rate of some millions of € are resulting from those failures, to the pleasure of the after-sales service departments of the pump manufacturers.

Especially the magnetic-drive pumps often are not worth a repair (economical total loss).

To achieve a competitive advantage many pump manufacturers are trying to find technologies to prevent those kinds of damages.

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Reasons for intermittent flow Reasons for intermittent flow

Emptying of the suction tank (as shown) Low plant resistance (pump operates far right on its curve) Closed suction valve Dirty filters or plugging in front of the pump High gas content (e.g. caused by swirls)

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The problem zone of classic The problem zone of classic magnetic coupled pumpsmagnetic coupled pumps

Slide bearings radial far inside

Low circumferentia

l speed

No real

sliding, but

mixed friction

Need for high

grade,

wear resistant

materials

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Intermittent flow: What happens Intermittent flow: What happens inside the pump?inside the pump?

The liquids tear-of is displayed in the Q-H-diagram as quick reduction of the volume

flow along the plant resistance curve !

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Intermittent flow: What happens Intermittent flow: What happens inside the pump?inside the pump?

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Intermittent flow: What happens Intermittent flow: What happens inside the pump?inside the pump?

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Intermittent flow: What happens Intermittent flow: What happens inside the pump?inside the pump?

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Intermittent flow: What happens Intermittent flow: What happens inside the pump?inside the pump?

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The bearings lie fully dry, though a rest of liquid is circulating in the pump:

Quasi dry runRemaining radial forces act upon the

bearings, which are not lubricated anymore:Hot run

Intermittent flow: What happens Intermittent flow: What happens inside the pump?inside the pump?

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Other state-of-the-art designs (1)Other state-of-the-art designs (1)

Bearings still fully in the

“problem zone”

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Bearings still fully in the

“problem zone” as well

Other state-of-the-art designs (2)Other state-of-the-art designs (2)

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The shaft less pump as right wayThe shaft less pump as right way

CORRECT: Slide bearings

to the outside!!!„Shaft less concept“

DISADVANTAGEOUS: Thin isolation shell is used as

bearing (Emergency and start-up bearings

still required)

DISADVANTAGEOUS: Bearings

difficult to reach

SUBOPTIMAL: Why not even farer to the outside??

WHY NOT THERE ?

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Shaft less concept MONSUNShaft less concept MONSUN

Sliding bearings radial outside to the maximum

possible

Magnetic driver positioned at

the inside

Simple bearing geometries

possible due to real sliding

Impeller and drum bearings form one single

unit

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Direct access to the bearingsDirect access to the bearings

Option: temperature control

Option: flushing - very simple

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Liquid tear-ofLiquid tear-of

Bearings are located in the wetted area

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Very low static head

Bearings lie dry

Liquid tear-of – worst caseLiquid tear-of – worst case

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The solution : A lubrication The solution : A lubrication reservoirreservoir

Rotating lubrication reservoir

Circular partition wall prevents empting of

the lubrication reservoir

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Cooling stream from electrical motor

Cooling rips at the casing guide the

friction heat away

Cooling of the lubrication reservoirCooling of the lubrication reservoir

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Conventional Conventional closed coupled designclosed coupled design

Advantage: Short axial dimension

Disadvantage: The assembly of the magnetic driver requires the final assembly of the electrical motor.

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Ball bearings located inside the isolation

shells opening: large bearing distance.

Pump is premountable and not depending on

variants. Good for stockholding!

MONSUNMONSUNball bearing conceptball bearing concept

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Universal shaft endUniversal shaft end

Alternatively: Journal part of a coupling…

… or shaft end of a standard pump

Flywheel mass

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MONSUN 50-200MONSUN 50-200

New magnetic coupling acts

additionally as magnetic thrust

bearing

Dynamic throttling gab regulates axial position of the rotor as well

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MONSUN 50-200MONSUN 50-200

Temperature sensor (Option)

1500 1/min:Δt10min´= 2,5 °C

3000 1/min:Δt10min = 10 °C

Temperature rise of emergency reservoirrelated to speed: (ca. values for water)

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Classic magnetic couplingClassic magnetic coupling

Same polarity in axial direction

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Axial reset capability of the classic Axial reset capability of the classic magnetic couplingmagnetic coupling

Number of green triangles

is important

100 N

100 N

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400 N

100 N

Alternating polarity in axial

direction

Axial reset capability of the Axial reset capability of the MONSUN type magnetic couplingMONSUN type magnetic coupling

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MONSUN type magnetic couplingMONSUN type magnetic coupling

Low losses of transferable nominal torque (circa 80% of classic coupling). Increasing the axial reset forces by a multiple.

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MONSUN as MONSUN as standard pump (ISO 2858)standard pump (ISO 2858)

MONSUN 32-200

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MONSUN in closed coupled designMONSUN in closed coupled design

MONSUN 32-200 F

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End of the presentationEnd of the presentation