High Viscosity Mixers

A formulation needs a high-viscosity mixer once it stops flowing back into the void created by the disperser blade. That behavior, rather than a specific viscosity number, is the practical threshold. A high-speed disperser works by drawing material into a vortex and shearing it as it circulates, so when the batch no longer returns on its own, the blade is only working the product immediately adjacent to it while the rest of the slurry in the vessel remains stationary. Restoring movement at that point requires a low-speed agitator that carries material through the vessel. 

Both units combine low-speed and high-speed agitation on independently driven shafts, and both are available with helical or anchor sweep low-speed options. The dual shaft configuration pairs one low-speed agitator with one high-speed element. The triple shaft adds a third independently driven shaft, allowing a second high-speed element to operate in the batch simultaneously. Formulations that require simultaneous bulk movement and more than one mode of high-shear input are the typical case for the triple shaft.

Hoist mounting raises the mixer assembly above the vessel, allowing a single machine to serve multiple tanks. That suits operations running several products or frequent changeovers, since one batch can be moved out for discharge or cleaning while the next tank is positioned.

Tank mounting fixes the mixer to a dedicated vessel, which simplifies the installation and is generally the better fit for continuous production of a single formulation. Both HHL-II and HHL-III units are available in either configuration.

Horizontal mixers move material along the axis of the vessel rather than around a vertical shaft, which works well for very stiff pastes and doughs that will not circulate under vertical agitation. They also discharge differently, since the geometry lends itself to emptying heavy material without relying on gravity flow.

Yes. Both the HHL-II and HHL-III are available in laboratory benchtop scale and production scale of up to 3,500 gallons within the same design elements, which make scale-up data meaningful. Developing a formulation for equipment that shares the agitator geometry and drive characteristics with the production machine reduces the risk that a process validated at a small scale will behave differently at volume.

Construction material affects all three. Stainless steel is required where the product cannot tolerate iron pickup or where sanitary cleaning standards apply, which covers most food, cosmetic, and pharmaceutical work. Carbon steel is a durable and more economical choice for products that are chemically compatible with it, such as many sealants, adhesives, and industrial pastes. Hockmeyer offers the HHL-II and HHL-III in either material.