The dual winder is fitted as a stand-alone unit at the end of an extrusion line for continuous plastic pipes and is used to wind the extruded pipe onto drums provided for this purpose.
The drums are of different sizes and are made of steel or wood; the largest drums have an outer diameter of 2.8 m and weigh up to 2 t when full. The maximum winding speed is about 50 m/min. The winders are designed for winding pipes with outer diameters ranging from 20 mm to 63 mm.
The laying unit holds the pipe in place while moving back and forth in the transverse direction during the winding process in order to lay the pipe neatly on the drum, or winding core; the travel speed in the transverse direction is therefore always dependent on the extrusion speed and the diameter of the pipe being wound.
The special feature of the dual winder is that it consists of two very compact winders positioned next to each other that wind pipe from the same extrusion line sequentially. At the end of the winding process, i.e. when the first drum is full, the laying unit automatically cuts the pipe and reinserts it into the other winder, which is waiting and was previously loaded with a second, empty drum, and the winding process then restarts automatically. This speeds up production, as it ensures that virtually no rejects are produced, allowing high-speed operation.