Immersion pumps - overview​​
Classification
Immersion pumps are flow pumps. The submersible pumps manufactured by Sager + Mack are axial-flow, normal-priming, single-stage centrifugal pumps.
(Depending on the source, these pumps are also described as submersible pumps).
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Construction
Immersion pumps are used in a vertical position, with the pump head immersed in the liquid but the motor remaining dry. The pump head is made of plastic or stainless steel, with welded connections (flange / screw connection / hose nozzle). The special tubular impeller of the Sager+Mack immersion pumps is fixed on a stainless steel shaft (not in contact with the medium).
The shaft is mounted in the dry area at the top, up to an immersion depth of 400 mm (without suction pipe extension).
From 400 to 600 mm immersion depth, the shaft requires a media-lubricated plain bearing made of high-quality silicon carbide (SIC)
Free suction mouth without resistances affecting NPSH.
Due to the use of solid material for the wetted components, these pumps offer very smooth running, high corrosion resistance and diffusion density, as well as robustness against abrasion and thermal distortion, therefore these machines are considered to be very operationally safe, reliable.
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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 with higher pressure. The discharge side is guided over the liquid level by means of a pipe fixed to the pump.
The delivery pressure as well as the delivery rate are determined by the pump performance (pump characteristic curve), the impeller geometry as well as the pressure losses on the pressure side of the system. The delivery rate as well as the delivery pressure can also be varied by speed control or bypass solutions.
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Power range
Pressure: 0 to 6 bar
Flow rate: 0 to 120 m^3/h
Viscosity: up to 100 mPas
Temperature: 5 to 95 °C (plastic) / 0 to 120 °C (stainless steel)
Power: 0.8 kW to 9.2 kW
Solids content: up to 25
Solids size: depending on pump size
Immersion depth: max. 600 mm (without suction pipe extension)
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Applications
Immersion pumps made of plastic or stainless steel are mostly used as transfer pumps or circulation pumps. They are mounted on tanks or installed in pump sumps that have level control.
They are in use in numerous processes, often using environmentally hazardous, corrosive substances or liquids, such as acid, alkalis, chemicals or chemically contaminated waste water.
The special impeller geometry of the centrifugal pumps from Sager+Mack offers advantages in the area of contaminated media with solids content. This impeller geometry also produces a relatively flat pump characteristic curve, which provides process advantages in many applications.
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Sealing technology
The rotating seal at the shaft transition to the motor is sealed to the outside by means of a labyrinth seal. Depending on the medium, this can be designed as a gas-tight* version.
*Not according to Technical Instructions on Air Quality Control
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Materials
Plastic (PP/PVDF), stainless steel (V4A), other special materials on request.
All parts in contact with liquids are, after prior design, media-resistant incl. the matching sealing materials.