20090086568 | CONTINUOUS BI-METALLIC TWIN BORE BARREL FOR SCREW EXTRUDER AND METHOD OF MAKING SAME - A continuous bi-metallic twin bore barrel is produced by forming first and second single bore barrels, centrifugally lining the bores of the single bore barrels with a bi-metallic liner, heating the single bore barrels to harden the linings, fastening each single bore barrel into a barrel machining jig, and cutting each single bore barrel along its length to expose its bore. The barrel machining jigs are fastened together such that two single bore barrels are positioned adjacent and in contact with one another and their bores are in communication with one another. The two single bore barrels are seal welded together to form a twin bore barrel. The twin bore barrel is removed from the jigs and clamped along its length. | 04-02-2009 |