Single screw kneaders

Figure 5.10 Schematic diagram of a single screw kneader. (Reprinted from Ref. 23 with kind permission from Gulf Publishing Co., Houston, Texas, USA.)...

Typical examples of the single screw kneader are the Buss Ko-kneader and the Baker-Perkins Ko-kneader. 

Fig. 13.1. Different types of extruders, a) single screw b) co-kneader c) non-intermeshing, mixing mode d) nonintermeshing, transport mode e) counter-rotating, closely intermeshing f) co-rotating, closely intermeshing g) conical counter-rotating h) self-wiping, co-rotating.

At times, low- or high-intensity blending alone can produce a suitable product for use by the fabricator. An example of this would be a polyvinyl chloride (PVC) blend used for several large-volume extrusion applications. More frequently, however, a compounding process is required to obtain the desired physical property. The five primary compounding processes used in the industry for controlling the above parameters are single-screw extrusion (SSE), twin-screw extrusion (TSE), continuous mixers, batch mixers, and kneaders. Table 18.1 summarizes key aspects of each process. 

Machine Type single screw extruder, twin screw extruder (co-rotating), twin screw extruder (counter-rotating), multi screw extruder, buss co-kneader, internal mixer, static mixer. 

EPR/PP Blends Lee and Chen [1983] investigated gamma-radia-tion-induced changes in the dynamic properties of PP, EPR and PP/EPR blends (Table 11.9). EPR pellets were ground in a Thomas-Wiley laboratory mill, and the EPR powder was dried at RT. PP powder was dried at 80°C in a vacuum oven for 2 h. The dried resins were mixed in a kneader, extruded using a single-screw machine and pelletized. The pellets were dried in the vacuum oven... 

Single screw extruders Buss-Kneader Twh screw extruders Multiple screw extruders ... 

Most of the research on reactive extrusion is performed in twin screw extruders, although a single-screw co-kneader has definite advantages if micromixing plays an important role. Franz (24) gave an overview of applications of reactive extrusion with a Busskneader in a paper discussing the polycondensation reaction of silanoles to produce silicon oils. Aeppli (25)... 

A particular type of single-screw extruder that can be used as a polymerization reactor is the co-kneader. Traditionally this machine is often used for processing of rubbers and foods. Though discovered in 1945 and commonly used in industry, its application is far ahead of theoretical understanding. 

SSE is single screw extruder PGE is planetary gear extruder KCK is Kishihiro Continuous Kneader... 

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