Aseptic and sterile tank processes demand absolute product integrity. Every gram of residue left behind in a mixer is lost yield. Every wear particle generated is a contamination risk. Every hour of unplanned maintenance is costly downtime. The Alfa Laval LeviMag aseptic magnetic mixer addresses all three challenges through a single engineering principle: a magnetically levitating impeller that never makes mechanical contact inside the tank.

How does a levitating impeller mixer work?

At the heart of the LeviMag is a radial-bladed impeller installed inside the process tank. A magnetic coupling transmits torque from the external drive unit through the tank wall, rotating the impeller without any shaft seal penetration. The unique design of the Alfa Laval magnetic coupling ensures the impeller levitates at all times — during mixing, during cleaning, and even when the tank is empty.

This permanent levitation means the impeller can run dry without damage. There is no mechanical contact between the impeller and the bearing surfaces during normal operation, which eliminates axial wear entirely. The female bearing is manufactured from silicon carbide to EN 12756, providing exceptional hardness and longevity. Because there is no seal to fail and no contact surface to degrade, wear-particle contamination is effectively removed from the process.

Why full drainability matters for product yield

Conventional bottom-mounted mixers trap product in seal cavities, bearing gaps, and stagnant zones around the impeller shaft. The LeviMag eliminates these dead spaces. Because the impeller floats freely, all process fluid drains completely from the tank under gravity. Alfa Laval describes this as "mixing down to the last drop" — and the design backs up the claim.

Full drainability also delivers superior CIP and SIP performance. During cleaning, CIP liquid and steam flow freely around every surface of the mixer internals with no hidden areas where residue can accumulate. The LeviMag supports CIP at temperatures up to 95 °C (at a maximum of 50 RPM) and SIP at up to 125 °C (at 50 RPM) or 150 °C when the impeller is stationary. This thorough cleanability reduces cycle times, lowers chemical and water consumption, and gives you confidence that every batch starts in a fully sanitised environment.

Hygienic construction and materials

The impeller and weld plate are manufactured from AISI 316L (UNS S31603), the industry-standard austenitic stainless steel for hygienic process equipment. All product-wetted surfaces are mechanically polished to Ra <0.8 µm, ensuring a smooth finish that resists biofilm formation and simplifies cleaning.

The drive rotor, shaft, and console flange are constructed from AISI 304 (UNS S30400). Standard seals are EPDM, with FPM and FFKM available as options for processes involving more aggressive media or higher temperatures. The gearbox uses USDA H1 food-compatible oil, and the painted gear motor meets DIN 12944 C2 (NSF/ANSI 51-2009e). For clean room environments, an optional drive unit finish uses a Permanent Bond Surface treatment (nsd tupH) that complies with FDA Title 21 CFR 175.300.

These material choices directly support compliance with EC Regulation 1935/2004 for food contact materials, FDA CFR 21 for non-metallic parts, and GMP requirements. When paired with the optional Q-doc package, the LeviMag provides full traceability from raw material to finished component.

Flexible sizing for tanks from 30 to 40,000 litres

The LeviMag is available in two model variants. The WP50 accepts 100 mm and 150 mm impellers and attaches to the tank via a clamp ring connection. The WP81 supports 200, 250, and 300 mm impellers and uses a flange-bolt connection. Both models are available with a standard console height or an extended console for insulated tanks.

Across these five impeller sizes, mixing speeds range from 10 RPM up to 800 RPM (for the 100 mm impeller). Larger impellers operate at lower maximum speeds — 480 RPM for the 150 mm and 200 mm sizes, 230 RPM for 250 mm, and 200 RPM for the 300 mm impeller. This speed range supports four distinct duty levels:

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  Sizing is straightforward using the Alfa Laval configurator or the published selection charts. However, two preconditions must be met: the liquid height must be equal to or less than 2.5 times the tank diameter, and the specific gravity of the media must not exceed 1.1. If your process falls outside these parameters, contact Euroflow or Alfa Laval Global Technical Support for a custom sizing assessment.
  
  
  The standard drive unit features an IPMSM operating at IE5 efficiency — the highest motor efficiency class available. It is enclosed to IP66 for protection against dust and high-pressure water jets. The motor requires a frequency inverter suitable for IPMSM motors; this frequency converter is not included in the Alfa Laval scope of supply and must be ordered separately.
  The drive uses a high-efficiency helical bevel right-angle gearbox lubricated with food-compatible oil. Maximum mounting angle is 0° to 45° from horizontal, and the motor must not point downwards. The standard finish is painted blue (RAL 5010) with fan ventilation. The clean room option replaces this with a Sealed Surface Conversion Treatment that produces a smooth, sealed body without a fan — ideal for controlled environments.
  For regions requiring specific certifications, three additional motor variants are available. The Premium/CUS motor (US/CA country code) delivers Premium efficiency class with power ratings of 0.37 kW (WP50) and 0.75 kW (WP81). The ATEX/EX motor (EU and general regions) carries an IE2/IE3 efficiency rating and safety class Ex db eb IIC T4 Gb. The LV Explosion Proof motor (US/CA) meets Class I Div 1 Group D requirements at Premium efficiency. All motor options maintain IP66 protection.
  
  
  Every LeviMag ships with a 2.2 certificate as standard. For industries where full supply chain traceability is mandatory — particularly pharmaceutical production and biotechnology — the optional Alfa Laval Q-doc package provides an extensive documentation set. This includes 3.1 material certificates per EN 10204 for all wetted parts, compliance declarations for EC Regulation 1935/2004, GMP, and FDA CFR 21 (covering elastomers, ceramics, and gear oil). TSE/ADI declarations and surface finish compliance declarations are also included.
  For installations in potentially explosive atmospheres, the Q-doc package covers compliance with ATEX directive 2014/34/EU. This level of documentation eliminates delays during audits and qualification processes, giving you a clear paper trail from raw material sourcing through final assembly.