Visco seal

A visco-seal must be designed into the shank of the screw to prevent resin from flowing out of the barrel and onto the floor. These seals are relatively simple and consist of a small channel that is spiral cut into the shank and in the same direction as the main flights of the screw, as shown in Fig. 15.12. The pressure in the feed channel causes the resin to flow out of the extruder through the annular region between the shank of the screw and the barrel wall and also down the chan-... 

Figure 15.12 Schematic of a visco-seal on the shank of a melt-fed extruder screw...

Visco-Seal R. [United Catalysts] Castor/ organoclay complex thickeno, thixo-trope for caulks, sealants, mastics. 

Functional property tests were conducted in duplicate. AACC (21) methods were used for the determination of water hydration capacity (Method 88-04) and nitrogen solubility index (NSI) (Method 46-23). Oil absorption capacity was measured by the procedures of Lin et al. (22) and oil emulsification by a modification (22) of the Inklaar and Fortuin (23) method. Pasting characteristics of 12.0% (w/v, db) slurries of the flours and processed products were determined on a Brabender Visco/Amylograph (Method 22-10). The slurries were heated from 30 to 95°C before cooling to 50°C to obtain the cold paste viscosity value. Gelation experiments were conducted by heating 15% (w/v db) slurries in sealed stainless steel containers to 90°C for 45 min in a water bath C3). 

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