ew pipe head for extrusion of polyvinyl chloride is said by its manufacturer to offer substantial processing advantages including higher melt pressure after the torpedo, which leads to a better welding effect. The pipe head, branded as the RK Streamliner, is made and marketed by High Tech Extrusion.
The new pipe heads are available for single-strand extrusion for pipe diameters from 12 - 400 mm and for double-strand extrusion from 12 - 63 mm and 20 - 110 mm respectively. Not only does the high pressure help produce pipe that can be more easily welded. Because of this higher melt pressure after the torpedo, high melt pressure in the die set is not necessary to produce good pipe. Shorter die sets can be used, and a wider pipe diameter range can be processed for each pipe head. The 30 - 35 % decrease in volume of the pipe head reduces resistance time of material, which means formulations with less heat stabilizer may be possible.
High Tech Extrusion (Korneuburg, Austria) is the umbrella brand name for four companies involved in plastics extrusion: Theysohn, Technoplast, Topf and Extruder-Komponenten Salzgitter....