Sigma blade impeller

Kneaders, Z- and sigma-blade, and Banbury mixers as shown in Figure 7.20, are generally used for the mixing of high-viscosity liquids, pastes, rubbers, doughs, and so on. The tanks are usually mounted horizontally and two impellers are often used. The impellers... 

For the batch mixing of thick pastes and doughs using ribbon impellers and Z- or sigma blade mixers, the tanks may be mormted horizontally. In such imits, the working volume of pastes and doughs is often relatively small, and the mixing blades are massive in construction. 

With high-intensity mixers, plasticizer is not held back all liquid ingredients are charged. Under cooling and agitation, resin and then other solids are added to the mixer vortex in a high-speed impeller mixer, or metered into a sigma blade mixer, at which point vacuum can be applied. 

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