| 摘要 |
PURPOSE:To produce moldings of many kinds each in small quantities at a high working rate and reduce the amount of scatter in additive concentrations by providing a plurality of sets of additive injection passages which can be connected to the base polymer extrusion passage and allowing certain additive passages to be at rest. CONSTITUTION:The main extruding machine 11 for base polymer pellets is connected through an extrusion passage 12 and a static mixer 13 to a die 14. To the extrusion passage 12, a plurality of sets of additive injection passages 161, 162... are connected, some of which are rested by selectively opening valves 171, 172.... Each injection passage is provided with a quantitative pump. Thus, the additive injection passages at rest can be used in preparation for extrusion molding of polymer of the next kind as well as it becomes almost unnecessary to wash the additive injection passages. |
