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How it Works

Benefits of choosing a ROSS PreMax Batch Ultra High Shear Mixer

What does a ROSS PreMax do?

A batch-style ultra-high shear device, the ROSS PreMax was engineered to address the limitations of rotor/stator mixers when processing higher viscosity products over 20,000 cP, or products requiring an extremely fine particle or droplet size distribution.

How does a ROSS PreMax work?

The ROSS PreMax is a patented (US Patent No. 6,000,840), top-entering batch mixer with Delta ultra-high shear rotor/stator technology. The Delta rotor is specially contoured for high pumping capacity and shear intensity. Product is drawn from above and below the rotor, then expelled radially through the stator slots at high velocity. This generates upper and lower vortices allowing for extremely efficient powder additions and rapid turnover rates. Very fine droplet sizes are achieved while solids are quickly wetted out instead of floating on the liquid surface.

Features at a Glance

Why Choose a ROSS PreMax?

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    Design - The PreMax is typically used as a stand-alone unit and does not require supplemental agitation for products up to 50,000 cP. For higher viscosity products, it is supplied in a multi-shaft mixer arrangement equipped with an anchor agitator.

  • product feature

    Scalability – PreMax Mixers are available from bench top laboratory models to very large production models (5 HP to 150 HP).

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    Sub-surface Powder Induction – Compatible with the ROSS Solids/Liquid Injection Manifold (SLIM) Technology. When the SLIM option is chosen, the mixer is equipped with a special rotor/stator that generates an intense vacuum in the high shear zone and sucks in powders sub-surface.

  • product feature

    Unparalleled Performance - The patented Delta rotor turns at tip speeds up to 5,000 ft/min. It produces highly superior dispersions compared to all other batch style mixers including high speed dispersers, traditional rotor/stators and immersion mills. The dispersion quality achieved in the PreMax is often comparable to one or two passes through a media mill.


Technical Data


  • 5 HP through 150 HP.
  • Driven by an explosion-proof motor designed for 230/460 volt, 3 phase, 50/60 Hz.
  • Mixing head hydraulically raised by an air/oil hydraulic lift.
  • Patented Delta rotor and stator.
  • Stainless steel type 316 wetted parts polished to an 80-grit finish.
  • Stellite rotor shaft bushing and shaft wear sleeve.
  • All non-stainless steel external surfaces coated with a two-part acrylic urethane enamel paint.
  • Clamping device to secure mix vessel.
  • Safety limit switches to prevent operation of mixer while in the raised position or without a vessel in place.

ROSS PreMax Batch Ultra-Shear Mixer Specifications

Photo Gallery

  • Hsmbatch4 Copy
  • Pm 150 Bottom R S View Copy
  • Pre Max with Slim Wand Attachment
  • Ross Pre Max Model Pm 120 (1) Copy
  • Ross Pre Max Ultra High Shear Mixer Copy
    • Additional Resources

      • Maximize pigment dispersion efficiency during pre-mixing

        Processing of pigments can be optimized by choosing an efficient pre-mixer that can disperse agglomerates as close as possible to the desired specifications. This leads to a reduction of mill passes, often the most time-consuming step of the pigment dispersion process. In some applications, specially designed rotor/stator pre-mixers can eliminate milling entirely.

      • Move your media mill process to an ultra-high shear mixer

        Specially designed rotor/stator mixers achieve ultra-high shear conditions which often result in extremely fine dispersions of pigments and other raw materials. More than just an ordinary `pre-mixer`, an ultra-high shear rotor/stator device can produce results comparable to one or two passes through a media mill.

      • Selecting the best rotor/stator combination for your batch process

        The batch rotor/stator mixer is an integral part of many manufacturing processes with various styles and models available in the market today. Determining the most suitable mixer configuration for your particular application is important in ensuring process-line efficiency and consistent finished product quality..

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