Back vented barrel for an extruding assembly

摘要

A vent passage (28) extends from a main extruder passage (24) and is spaced from and between a feed extruder passage (26) and a back surface (16) of the barrel (10). The barrel (10) is characterized by the vent passage (28) being disposed to extend from the top surface (12) into the main extruder passage (24) and a vent passage adapter (36) in the vent passage (28) for controlling the venting of gases. The vent passage adapter (36) includes a restrictor member (44) extending downwardly from a mounting plate (38) to form a restricted passage (46) with a screw cover (40). The restrictor member (44) is removably attached to the mounting plate (38) whereby it may be removed for a less restricted venting of gases.