zhoushan shenglong machinery co.ltd, which is located in zhoushan city,zhejiang province, is a main professional manufacturer of making screws and barrel for more than ten years. we specilized in design and manufacture of a full series of screws and barrels, applied for various extruding machines and plastic injection molding machines. in addition, we also design and manufacture screws with special alloys and special flight geometry to meet specific customer applications. we not only offer the best possible screws and barrels, but also provide solutions to help customers solve extruding and injection molding problems