Inline High-Shear Mixer

What is the Inline High-Shear Mixer?

An inline high-shear mixer places a rotor-stator head in a pipeline housing so that product passes through the shear zone in a single or recirculating loop. It gives narrow particle size distributions and scale-up from laboratory to production.

Overview

The inline mixer has a rotor-stator head in a closed housing with an inlet and an outlet. The product is pumped through, typically from a vessel and back, and experiences a defined number of passes through the shear zone. This produces a narrower droplet and particle size distribution than a batch mixer. Laboratory inline units handle flows of 10 to 500 L/h with rotor speeds up to 26,000 rpm, and the same generators are often available at pilot and production scale, which makes scale-up predictable. The housing can be jacketed and fitted with sanitary connections such as tri-clamp. Some models combine pumping action with shear, so an external pump is not needed. The design reduces air entrainment, since the head is always flooded, and is suited to emulsions, pastes and dispersions with viscosities up to about 10,000 mPa·s.

How does it work?

A high-shear mixer rotates a rotor at high tip speed, commonly 10 to 40 m/s, inside or next to a fixed stator. Fluid is drawn axially into the rotor, accelerated outward, and forced through the narrow gap between rotor and stator, typically 0.2 to 1 mm, and through slots or holes in the stator. In the gap the fluid experiences very high shear rates, often above 20,000 s⁻¹, plus turbulence and cavitation, which break droplets and particles and wet powders. Disperser-type heads use a toothed or saw-tooth blade in an open vessel. Main components are the motor and drive, the mixing head with interchangeable generators, a shaft with seals, a vessel or inline housing, and speed control. Results depend on tip speed, gap, generator geometry, viscosity and batch time.

What are the key features?

• Closed pipeline housing with inlet and outlet connections
• Defined number of passes through the shear zone
• Narrow droplet and particle size distribution
• Same generator geometry available for scale-up
• Flooded head that limits air entrainment
• Sanitary tri-clamp connections and jacket options

What are the technical specifications?

A typical inline high-shear mixer configuration offers flow rate of 10–500 L/h, rotor speed of Up to 26,000 rpm, tip speed of Up to 40 m/s, motor power of 0.5–7.5 kW, viscosity range of Up to 10,000 mPa·s and connections of Tri-clamp or threaded. Values are indicative of the product class; the exact figures for each configuration are confirmed on the quotation and the calibration documents supplied with the instrument.

Which applications is it used for?

The Inline High-Shear Mixer is used in emulsion scale-up studies, pharmaceutical dispersion, cosmetic lotion preparation, food emulsions and sauces and recirculating dispersion of pigments. Across the wider High-Shear Mixers class, laboratories also deploy it for emulsion and cream preparation, pigment and filler dispersion and pharmaceutical suspension development.

Which standards and certifications apply?

Relevant standards and methods include IEC 61010-1, EN ISO 12100, ISO 13320, ASTM E2651 and GB 4793.1. Certification candidates for this model are CE, RoHS and ISO 9001 manufacturing; each is to be confirmed for the specific configuration before shipment, and certificates are supplied only where they have been issued.

Secure the mixer on a stable stand or clamp and keep the head fully immersed before start-up to avoid air entrainment and dry running of the seal. Use guards and emergency stops, and never operate with loose hair or clothing near the shaft. Keep the gap between rotor and stator clean, since worn generators lose shear efficiency and should be inspected regularly. Flush or clean-in-place between batches to avoid cross-contamination. Control temperature, since shear heats the product, and use jacketed vessels or cooling where needed. Sanitary seals and polished surfaces are important for pharmaceutical and food work. Comply with IEC 61010-1 and machinery safety standards, and record speed, time and temperature for batch documentation.

How do I select the right Inline High-Shear Mixer?

Choose an inline high-shear mixer when narrow size distribution, scale-up predictability or continuous processing matters. Batch units are more flexible for small trials. In the RFQ, specify flow rate, viscosity, pressure, connection type, housing material and whether a pump and jacket are needed.

How does it compare with other High-Shear Mixers variants?

Select a high-shear mixer by batch size, viscosity, target particle or droplet size and process type. Batch rotor-stator mixers suit volumes from 0.1 to 100 L and offer interchangeable generator heads. Inline models process continuous or recirculated flow and give narrower size distributions. Vacuum emulsifiers combine shear with degassing and heating for cosmetics and ointments. Dispersers suit pigment and filler wetting in coatings and inks. Powder-induction designs draw powders into the liquid to prevent lumps. Check tip speed, motor power, generator options such as coarse, medium and fine slots, and materials of construction such as 316L stainless steel. Consider cleanability, sanitary design and seals if the products are pharmaceutical or food grade. Verify noise levels and safety guarding, and ask for trials if particle size specifications are critical.