Extrusion surge suppressor and method

摘要

An apparatus and method for extruding an elastomeric polymer which is subject to periodic pressure surges. The apparatus includes a barrel having an upstream portion and a downstream portion, a hopper positioned for delivering polymer to the upstream portion of the barrel, a shaft rotationally mounted within the barrel and a drive means for rotating the shaft. The shaft has a conveying screw flight for conveying polymer downstream from the hopper through the barrel. The barrel has a discharge port located downstream of the hopper. A surge suppressor is provided on the shaft for reducing the pressure and flow rate surges in the polymer. The surge suppressor includes a screw flight downstream of the discharge port for urging the polymer upstream toward the discharge while permitting a portion of the polymer to flow downstream into the surge suppressor. A polymer seal is provided downstream of the surge suppressor.