High Shear Mixers

What is a High Shear Mixer?

In a high shear mixer the combination of high speed and close rotor / stator tolerance creates a high energy zone where liquid / liquid and liquid / powder mixtures are rapidly homogenised.

Mixer head design is matched to process requirements in order to achieve optimum particle size and maximise mixing efficiency, whilst minimising aeration.

High Shear Mixers are commonly used to emulsify oils in water and in the creation of ultra-smooth powder-in-liquid mixes.

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Bottom Entry High Shear Mixer

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In-line High Shear Mixer/Pump

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Why a Greaves
High Shear Mixer?

  • Scalable from laboratory to bulk, delivering consistent results regardless of batch size
  • Sector leading rotor/stator gap tolerances, maximising shear rate and minimising
    batch times
  • Head/baffle/impeller options to optimise flow and shear
  • Class-leading safety features and lifting systems, CE Certificate of Conformity
    ATEX variants to Zone 0 & Zone 20 IIC T4
  • De-aeration capability
  • Abrasive and corrosive resistant options
  • Stator options for particle size down to 3 microns
  • In-line and bottom entry variants
  • High pressure & vacuum shaft sealing options

Shear Stator Options

general purpose shear stator
General purpose shear stator
emulsification shear stator

Emulsification shear stator

1.5mm shear stator

1.5mm shear stator

500 micron shear stator

500 micron shear stator

Shaft sealing options

Shaft seal selection is a critical factor in specifying any mixing system. Greaves offers a comprehensive range of high performing seal options to meet the most demanding process requirements.

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High Shear Mixers FAQ’s

At high rotational speed, the precision engineered impeller rapidly draws unmixed material into the rotor head. The outer face of the impeller then forces the same material into the mixing zone. This is where the fine tolerance stator /impeller gap creates intense shear forces which mix the product as it passes through the stator back into the mixing vessel.
See more here: https://www.youtube.com/watch?v=vUNxoMonf10&t=6s

3 key reasons:

  • The industry-leading shear-rate and flexibility of Greaves’ High Shear Mixer. This performance is achieved by (a) class-leading technology – rotor-stator tolerances and (b) Greaves’ unique adjustable baffle plate system. These factors ensure that a completed mixing cycle is achieved quicker and consistently so the resulting mix has superior stability and longer shelf life.
  • Greaves are experts in shear mixing. We collaborate with our customers to combine our engineering skills with their specific product knowledge. We work with you consultatively by listening, learning and offering blending solutions that consistently exceed expectations
  • Greaves engineers always aim to provide the most sustainable solutions:
    1) Our mixing performance calculations not only deliver optimum mixing efficiency but also minimise process time and energy consumption.
    2) Batch removal is designed to minimise residual material, thereby cutting waste product and optimising clean-down time with minimum consumption of cleaning water / solvent

We are a very approachable family company who deal with customers from diverse backgrounds with varying degrees of process knowledge. Make contact and we will guide you to the best equipment for your needs!

A high shear mixer usually involves a rotor-stator type mixing head for emulsification of material with minimum liquid surface displacement. Conversely, HSD mixers often create a vortex, leading to down-thrust which enables rapid wetting-out of challenging “difficult to wet” powders or agglomerates. Generally, HSD mixers are more effective processes with higher loading of powders, pigments or dense, buoyant solids – including food processing!
Usually yes. The precision engineered tolerance between the rotor and stator combines with a high peripheral speed. This is so intense the particles tend be reduced in size and this contributes to consistency throughout the mix. Where particle size reduction is a key objective we can offer options from a range of alternative stators.
Greaves offers a complete range of solutions from Zone 0 & 20 to Zone 2 & 22. These apply to all mixer types with Notified Body certification. Greaves experienced team will be pleased to provide assistance in solve any hazardous area mixing requirements. We can also assist you with DSEAR if you don’t know which risk category your flammability materials fall in to.

The shear rate of a high shear mixer is calculated using the shaft speed, rotor diameter and the gap between the rotor and stator:-

In use the shear rate of Greaves High Shear Mixers can be adjusted using the rotational speed control. This enables the operator to control the energy input, thereby affecting flow rate and particle size. Our mixing experts will also be pleased to advise on selection of the most appropriate rotor stator head for your applications.

In a word – Hugely!
Viscosity is a measure of a fluid’s resistance to flow. Measured in centipoises or Brix, it plays a key factor in determining which mixer types are appropriate, their diameters, speeds and the power required to drive them. Get in touch with our team who will be pleased to help.

Since 1947, so almost 80 years!