Sigma blade

Fig. 38. Various mixer types for viscous pastes (a) the change-can mixer, (b) rake mixer, (c) double-rake mixer, and (d) sigma-blade kneader.

Many other blade designs have been developed for specific applications. The double-naben blade (Fig. 18-41 is a good blade for mixes which ride, that is, form a lump which bridges across the sigma blade. 

Screw-Discharge Batch Mixers A variant of the sigma-blade mixer is now available with an extrusion-discharge screw located in the saddle section. During the mixing cycle the screw moves the material within the reach of the mixing olades, thereby accelerating the... 

Kneadermaster This mixer (Patterson Industries, Inc,) is an adaptation of a sigma-blade mixer for continuous operation. Each two... 

Since paste mixing is not within the scope of this section, such widely used paste mixers as the sigma blade and banbury types will not be covered here but instead are discussed in Sec. IS. 

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... 

Hah, K. R. and Godfrey, J. C. Trans. Inst. Chem. Eng. 46 (1968) 205. The mixing rales of highly viscous Newtonian and non-Newtonian fluids in a laboratory sigma blade mixer. 

Sigma-blade mixer, in bar soap manufacture, 22 751 Signaling smokes, 5 827, 830 Signal processing in the element (SPRITE), 29 162-163... 

Mixing of the crystalline ingredients of oxidant, fuel elastomer binder (butadiene-2-methyl-5 vinyl-pyridine copolymer plasticized with the formal of diethylene glycol monobutyl ether) 26% by vol is done in a sigma blade mixer. The completed mix is blocked in a hydraulic press to form a chge suitable for extrusion. The extruded strand is cut into grain blanks which are cured at... 

In the manufacture of cellulose ester plastic, the appropriate ester is blended with plasticizer and other additives, such as stabilizers, ultraviolet inhibitors, dyes, and pigments, commonly in a large sigma-blade mixer. The mixture thus obtained is heated to its softening temperature and kneaded until it is homogeneous. This is done on hot milling rolls, in a compounding extruder, or in a Banbury mixer. The molten mass of plastic that results is formed into small rods or strips that are then cut into cylindrical or cubical pellets, which ordinarily have dimensions of about J inch (3 millimeters). See Fig. 2. 

A pilot scale evaluation of a 15 gallon Beken Duplex Mixer for propellant manuf, conducted at PicArsn, indicated that it can be successfully substituted for other mixers, such as a sigma blade mixer... 

Acrylic latex sealants. Basic acrylic latex sealant formulations were compounded in a sigma blade mixer, as shown in Table 3. The water-borne silanes were then incorporated into a base. Standard wet and dry peel adhesion determinations from various substrates were performed periodically in accordance with ASTM C794-8. 

The expts were conducted in stainless steel sigma-blade type mixers with proplnt mixing capacities of 60, 600 and 2000 lbs, respectively. Radioactivity measurements on samples taken from various locations in the batch at different mixing times were performed with a sodium iodide scintillation detector system... 

BMC is processed by premix techniques, using the standard sigma-blade mixer. The only change is the use of Group 2a metal oxides and hydroxides. 

In the standard wet granulating method used to produce tablet feed in the pharmaceutical industry, sigma blade or heavy duty planetary mixers are often employed [12]. These machines may handle 220 or 440 lb (100 or 200 kg) batches and employ 7 to 10 hp (5.2 to 7.5 kW) drives to knead and... 

Fillers may be added to low-viscosity resins by conventional sigma-blade mixer or the same type of equipment used for mixing paint systems. Three roll mills are generally employed for more viscous systems to obtain thorough wetting of the filler by the resin matrix. 

Salt Attrition. The crude is ground in a ball mill or a double-arm, sigma blade mixer in the presence of a large excess of sodium chloride and an organic solvent such as diethylene glycol or xylene to give the green-shade, beta copper phthalocyanine blue. 

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