PLANETARY ROLLER

The planetary roller extruders are mostly used for processing heat-sensitive compounds, viz. rigid or plasticized PVC formulations [Collins, 1987 Anders, 1979]. The planetary roller section can also be used as an add-on mixer to SSE to improve the mixing performance [Rust, 1983 Huszman, 1983]. Degassing and addition of fillers or reinforcements into melt has also been carried out. 

Anonymous, Planetary Roller Extruder, Battenfeld Extrusion-technik (1989). 

Plain strain compression test 866 Planetary mixers (also Gear pump) 603, 623 Planetary roller extruders 620, 641, 690... 

Special types (ram extruder, planetary roller extruder, cascade extruder, Weis-senberg extruder). 

Anonymous, MPC/V,AP V Chemical Machinery, Bako-Perkins, Techn. Inf (1989e) Anonymous, Planetary Roller Extruder, Battenfeld Extrusiraiteclmik (1989f)... 

There are several types of extruders, which incorporate more than two screws. One relatively well-known example is the planetary roller extruder, see Fig. 2.11. 

Figure 10 Appearance of a planetary roller extruder. The arrows on the left side indicate the movements during extrusion.

Arising from these considerations the planetary roller extruder seems to be particularly suitable for the wet and melt agglomeration of pharmaceutical powder blends. In the following is described a system for continuous wet granulation based on a planetary extruder and the usage thereof. 

As mentioned earlier, the granulation is realized through a planetary roller extruder. By the feed screw the material is taken into the granulation section of the planetary system (Fig. 12). 

The planetary roller extruder (PRE) has a rotating, geared central shaft and a stationary geared... 

Planetary Roller Extruders Principle Components and Operating Principles... 

Planetary roller extruders (PRE) have been used for many years in the compounding of temperature sensitive polymers and rubber compounding [57-64]. PREs are comprised of long helically geared components comprising a driven central shaft, freely rotating planetary spindles and a stationary, temperature-controlled outer cylinder, all of which must closely intermesh. The planetary spindles are located between the central shaft and the outer cylinder. To illustrate this relationship. Fig. 12.43 shows... 

Figure 12.43 Cross-sectional view of a planetary roller extruder from US Pat. 4,192,617 showing reiationship of the helically geared rotating central spindle, planetary spindles, and the outer cylinder.

Figure 12.44 Side view of a typical, one processing section planetary roller extruder from US Patent 4,192,617 showing relationship of the planetary section components and a single-screw feed section and fully flighted planetary spindles.

Figure 12.48 Schematic diagram from EP0340407A2 of a planetary roller extruder with a single flighted feed section added to the central rotating cylinder ahead of the first planetary roller section.

Molten polymer is delivered by the planetary extruder to the exit of the extruder by the forwarding, or pumping, action of the turning central shaft, the planetary rollers in cooperation with the outer cylinder wall. The uniformity of the discharge pressure will be dependent on the rotational speed and the design characteristics of the planetary rollers and the helix angle of the planetary gearing. The level of the... 

Rust H. Planetary roller extruder with thrust ring. DE 19720916 C5 2014 (May 15). 

Macromolecular Materials and Engineering 287,No.ll, 12thDec.2002, p.815-23 COMPOUNDING UNIT PLANETARY ROLLER EXTRUDER... 

A description is given of a novel planetary roller extruder developed by ENTEX for the continuous mixing of rubbers and plastics. The efficiency of this extruder for compounding rubbers is demonstrated by a comparison with a discontinuous internal mixer. 

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