VARISHEARS® And Super Productivity

The unique Varishear® Mixer manufactured and marketed by Jones Industrial Mixers is a superb productivity machine. It is capable of handling mixes of up to 100000 centipoises. The Varishear is also particularly popular in the paint industry, where its super productivity comes most to the fore in dispersion processes. Numerous different factors contribute to achievement of the best dispersion results in the shortest possible process time and certainly impellers play a critically important role. Since the Varishear impeller is so unique in its design and variability, we will highlight some of the main productivity features through a discussion of the critical impeller function in dispersion mixing.

The ratio of impeller to tank dimensions is important in any mixing application. Generally a ratio of 1/3 is required with standard high shear dispersion blades, but this does, however, also depend on the nature of the batch and the mixing objective.

Let us assume a powder product very difficult to disperse in a liquid, and where the liquid is non-viscous. This is the most difficult type of dispersion application, because a product that is hard to disperse requires high kinetic speeds to achieve results. In our section on dispersion theory elsewhere on this site, we explain that cycling (compared to turbulence) is essential and that proper balance of the dispersion process will lead to successful and efficient results.
As the liquid is non-viscous, turbulence will rapidly result in a tank of 1/3 ratio. With a standard impeller this dispersion would be very difficult, but with adaptable impeller arrangements, such as available in Varishear dispersers, the number of vanes can be reduced (from 8 to 2 if necessary) or the diameter varied by opening and closing the vanes. Proper cycling can be achieved with a high kinetic speed maintained, by maintaining the same impeller outside dimensions (but as stated with the lesser number of vanes).

Let us now assume that the liquid is very viscous. Two options arise with adaptable impeller arrangements. The number of vanes can be increased, until cycling occurs. With the Varishear machines, the vane angles can also be varied and cycling may occur with an intermediate number of vanes. The ability to vary the impeller diameter by opening and closing the vanes and to also vary the number of vanes themselves enables a great range of adaptation to the product needs.
Batch times have been shown to reduce by 65% and more by efficient, fast dispersion processes with the Varishear Mixer.

The question of impeller/tank ratios is mainly a matter of power. In fact, if there is an excess reserve of power available, then the same Varishear impeller might treat in the same size tank, either a very liquid or a very viscous product. The variation in power absorbed will be high. If a fluid or non-viscous product absorbs 1 kW, then a very viscous product could absorb 30 or 40 kW. Power savings in any particular application of up to 25% may be achieved by careful impeller selection.

The Varishear impeller is not limited by the 1/3 ratio rule. It is easily capable of operating between ratios of 1/2 to 1/5 depending on the viscosity of the material. This enormous variation demonstrates the flexibility of the Varishear impeller, which can handle differences in power or differences in impeller/tank ratio.

Truly a super productivity mixer!

Please contact us for further information on productivity advantages of the Varishear® Mixer and a quotation for your plant. Industries where the Varishear has already been successfully applied are listed below.

VARISHEAR® EXTENDED APPLICATIONS LIST WORLDWIDE

FOOD INDUSTRY 

Alcohol – ageing

Apple (puree)

Aromatic extracts

Biscuits

Butter – colouration

Cheese

Chocolate – drinks

Citrus – juice extracts

Confectionery

Cotton – seeds

Emulsions

Fillings – biscuits

Fish (pastes-wastes)

Flavourings – various

Food – various

Gravies

Homogenising

Honey – clarification

Insecticides

Lotions (all)

Lipstick

Magnesia (milk)

VARIOUS 

Fibreglass Gel Coats

Foundry Mould Coats

Pharmaceutical Emulsions and Solutions

Rubber Solutions (Tyre Industry)

Sealants and Low Viscosity Mastics

Shoe and Floor Polishes

Textile Pastes and Dies

Tile Adhesives (PVA and Bitumen Bases)

Wax Crayon Solutions