Immersion pumps - overview​​
Classification
Immersion pumps are flow pumps. The submersible pumps manufactured by Strobl Pumpen are axial-flow, normal-priming, single-stage or multi-stage centrifugal pumps.
(Depending on the source, these pumps are also described as submersible pumps).
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Construction
Submersible pumps are used in a vertical position, with the pump head submerged in the liquid but the motor remaining dry. Alternatively, a submersible motor can also be used if the motor is also to be submerged in the liquid or must be protected against flooding.
The entire pump is made of iron or steel (see materials).
The pressure connections are equipped with flanges according to DIN or ANSI. The suction connection is fitted with an inlet strainer on most versions.
In the VS6 version, the suction connection is fitted with a flange to DIN or ANSI.
Motor technology: Asynchronous motors in IMV1 design are used as drive motors. The three-phase motors are designed as standard in efficiency class IE3 in accordance with EN 60034-30. Motors in efficiency class IE 4, NEMA Premium or Ex versions are optionally available.
Drive sealing: Sealing by throttle, dry-running gas seal or mechanical seal (single or double-acting)
Explosion protection - ATEX: Explosion-proof versions are available as an option.
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Functionality
The axially inflowing liquid enters the pump head directly via the suction mouth of the pump and is accelerated by the rotary motion of the impeller and conveyed to the discharge side at a higher pressure. Depending on the design, the discharge side is guided over the liquid level by means of a pipe fixed to the pump or inside the pump.
The delivery pressure and the delivery rate are determined by the pump performance (pump characteristic curve), the impeller geometry and the pressure losses on the discharge side of the system. The delivery rate and the delivery pressure can also be varied by speed control or bypass solutions.
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Power range
Pressure: to 16 bar
Delivery rate: to 360 m^3/h
Viscosity: up to 150 mPas
Temperature: depending on version on request
Power: 0.55 kW to 110 kW
Solids content: up to 25
Solids size: depending on pump size and impeller design
Immersion depth: max. 25m (without suction pipe extension)
Connections: Flanges according to EN 1092-2 or ANSI B16.5
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Applications
The submersible pumps are mainly used for pumping clean liquids from containers and tanks. The double casing pumps of the VS6 version are specially designed for systems with low NPSH values and offer the possibility of pumping a wide range of aggressive liquids from the chemical or petrochemical industry due to the available material variants.
For applications with solids-laden media, the VS4 versions of the submersible pumps can also be combined with impeller variants from the waste water series, such as channel or vortex impellers.
The submersible pumps are used successfully in various areas, such as emptying tanks and containers, pumping liquids in plants, water treatment as well as in offshore plants and refineries.
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Sealing technology
Depending on the version, the rotating seal at the shaft transition to the motor is equipped with a throttle, a single-acting mechanical seal, a double-acting mechanical seal or a magnetic coupling*.
There are a number of different variants in terms of design and material combinations.
Explosion protection - ATEX: Explosion-proof versions are available as an option.
The drive shaft is realised by means of a throttle (for VS4), dry-running gas seal (for VS4) or mechanical seal (single or double-acting (for VS1, VS6)).
*A magnetic coupling is available as an option, but only for the VS1 and VS6 variants.
This variant is very critical due to potential gas accumulation in the pot and requires intensive technical clarification if necessary.
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Materials
Materials: Depending on requirements, the housings are made of cast ironnor stainless steel.
Special materials are always possible on request: e.g. cast steel, chrome steel, stainless steel, duplex, super duplex, super austenite
All parts in contact with liquids are, after prior design, media-resistant, including the appropriate sealing materials.