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Liverani Miniverter Flexible Impeller Pump

Viscous Fluids & Food Grade Pump

Liverani Miniverter Flexible Impeller Pump
Flow Rate Up to 5.76 m³/Hr
Max Head (pressure) Up to 32 M
Max Temperature Max. 100°C
Max Viscosity Up to 50,000 cP
Outlet Sizes ¾” BSP M up to 1½” RJT

Flow Rate Up to 5.76 m³/Hr
Max Head (pressure) Up to 32 M
Max Temperature Max. 100°C
Max Viscosity Up to 50,000 cP
Outlet Sizes ¾” BSP M up to 1½” RJT

The Liverani Miniverter Flexible Impeller Pump offers all the advantages of the FEP MINI and MIDEX pumps but with integrated variable speed control. This combined with the SS316 materials of construction and various sealing and impeller material options, enables these flexible vane pumps to be used in a plethora of different applications. 

Flexible impeller pumps are very versatile in applications that are suitable for thanks to several design benefits. Firstly, thanks to their supple vanes they are able to handle not only clean, light fluids, but also viscous, solid laden slurries. Secondly, the multiple materials the impellers are made out of mean they are compatible with many fluids e.g. NBR for fats and fuels, EPDM for chemicals and hot fluids and natural rubber for water based liquids. Flexible vane pumps with EPDM and NBR impellers are able to be supplied with FDA Certification, making them a popular electric food grade pump solution. Their low shear operation also makes the ideal for handling delicate fluids that can be altered by other pump designs.

Flexible impeller pumps are also renowned for their dry self-priming capability, making them ideal for applications where good suction lift capacity is needed such as the emptying of tanks, sumps and other containers. 

It is possible to adjust the speed range of the Miniverter flexible impeller pump from 285 to 1400 rpm, and to choose the direction of flow using the integrated potentiometer and rocker switch fitted to the terminal box whilst still retaining its standard IP55 protection rating. Carrying handles and trolleys are available as optional accessories to increase the Miniverter flexible vane pumps’ portability when being used for a variety of site applications.

Read more about the working principle of flexible impeller pumps and what processes they are commonly selected for here.

Features of the Miniverter Series Flexible Vane Pump:

  • Close coupled flexible impeller pump with variable speed (inverter dial integral to terminal box)
  • Smooth, pulsation free flow for the easy pumping of shear sensitive liquids.
  • Solids passage capability - 3mm (MINI), 5mm (MIDEX)
  • Self priming up to 6m without requiring a non return valve.
  • Pumps can be operated in either direction through a reversing switch mounted on the panel.
  • Pump head can be rotated and mounted in several positions.
  • Wide range of connection types available including DIN, BSP Male & Female, Triclover, SMS, RJT, Friederich, Garolla, and Macron
  • Stainless Steel AISI 304 Pipe Fittings for easy integration of the pump into existing applications are available.
  • NOTE: flexible vane pumps are supplied with BSP connections as standard with hose fittings, clamps and seals included.
  • Flexible vane pump heads are SS316.
  • Optional manual (MINI) and spring loaded (MIDEX) by-pass, these units can also be used with nozzles for dispensing applications.
  • Automatic drum filling kits complete with stainless steel nozzle, non return valve & pressure switch are available if required
  • Optional carry handles and trolleys to increase portability



Material options for the Miniverter flexible impeller sanitary pump:

Description Stainless Steel AISI 304 Stainless Steel AISI 316 Nitrile (NBR) Natural Rubber (NR) Neoprene (CR) EPDM Silicon (VMQ) St. St. / Graphite / NBR Tungsten Carbide / NBR Tungsten Carbide / Viton
Part List
Pump Body X X
Impeller X X X X X
Mechanical Seal X X X


1.Changes in Mechanical Seal Materials are at cost. All pumps are supplied with Ceramic / Graphite / NBR as standard.

2.Changes in Impeller Materials are Free of Charge. All pumps are supplied with Natural Rubber Impellers as standard.

3. EPDM and NBR impellers are available with FDA certification

The beauty of the Mininverter flexible impeller pump is it's versatility. Thanks to the following features it is an option that can be applied to many application requirements. 

  • Handles solids up to 5mm – Supple impellers bend to pass viscous fluids and slurries up to 50,000 CP and solids without damage to the pump
  • Applies low shear – Ideal for delicate, shear sensitive fluids that can be damaged or altered by other pump types such as cream that gets thicker when whipped.
  • Reversible operation – Allows cleaning solution to be ran through after use for hygienic pump applications, and tank to tank transfer applications.
  • FDA approved – EPDM and NBR impellers with FDA certification for food grade pump assurance. Stainless sanitary enclosures and Tri-clamp couplings available.
  • Smooth, steady pumping – Provides a consistent flow ideal for dosing ingredients, chemicals and process fluids and filling finished product into packaging.
  • Self-priming up to 6m – Enables the emptying of tanks and drums without a non-return valve or regular manual priming being required. 
  • Various moutning positions - Allows for versatile installation to fit the pipework at hand
  • Various accessories available - Trolley for portability, bypass valve for nozzle dispensing, control panel, variable speed drive, level sensors and dry run protection

Flexible impeller pumps are a versatile design of pump for relatively low pressure applications, mainly with thanks to their impellers being produced in a wide range of materials for fluid compatibility including food grade applications. As the impellers are made of a supple, rubber type material that is able to bend, flexible vane pumps are also able to handle viscous fluids and those with solid content without causing damage. They also apply little shear to the pumped medium, making them suitable for shear sensitive fluids and their ability to be operated in reverse makes them ideal for tank to tank transfer. These design benefits make them suited to many applications including:

Marine Applications Industrial Applications
  • Contaminated bilge water pumping
  • Oil and lubricant transfer
  • Black and grey water pump
  • Sludge and slurries
  • Fish waste pump
  • Tank to tank seawater transfer
  • Food processing and transfer
  • Dairy products
  • Brewery and distilleries
  • Chemical pumping
  • Waster water pump containing solids
  • Oil and lubricants
  • Viscous fluids, sludges and slurries
  • Soaps, creams and gels
  • Paints, glues and detergents

Castle Pumps are fully accredited to enable you to buy with confidence. Our accreditation includes: Our accreditation A division of the CTS Group, Part of Flow Max Ltd.