Extrusion International 3-2021

37 Extrusion International 3/2021 Since its foundation in 2006, Mole- cor has seen enormous growth and is known today as the world’s largest and most experienced PVC-O pipe manufacturing com- panies with production plants in Spain, Malaysia, South America and South Africa. “Thanks to our enormous wealth of experience, we make top-quality pressure pipes with an unparalleled price/ performance ratio,” Dolores Her- ran, Business Development Direc- tor at Molecor, presents the com- pany’s special competence. PVC is an ideal raw material for pipe production, recommending itself by its range of good properties at a relatively favorable price. When compared with the competing metal pipe sector, plastic pipes score with corrosion resistance and easier laying; when compared with PE pipes, PVC pipes win by their about 15 to 20% lower ma- terial price. A further special feature of PVC-O pipes is their profile of ideal me- chanical attributes with higher free section for more flow trans- portation resulting from a special production method. This consists of two process steps: production of a thick-walled preliminary pipe on a standard PVC pipe extrusion line, and subsequent heating this proforma pipe and further form- ing of the pipe by orientation in a special mold. While the length of the pipe remains unchanged, this leads to its external diameter being almost doubled, with a sig- nificant reduction of its wall thick- ness. During the orientation pro- cess, the polymer molecules orient themselves in the hoop direction , with the result of high mechani- cal properties: impact resistance, no crack propagations, fatigue resistance among others . When compared to conventional PVC-U pipes, PVC-O pipes come with up to 50% thinner wall thicknesses for the same pressure class. The resulting lighter weight per me- ter facilitates handling on build- ing sites enormously. This equally applies to comparisons with metal or polyolefin pipes. These advan- tages are driving the increasing global demand for PVC-O pipes in all sectors of water management. Molecor currently operates it- self seven extrusion lines from battenfeld-cincinnati at its main production plant in Loeches to produce PVC-O pipes with exter- nal diameters ranging from DN90 to DN1,200 mm. All of these lines are equipped with high-perfor- mance parallel twin screw ex- truders from the twinEX series, PVC-O spider pipe dies with in- ternal cooling and all necessary downstream components, such as vacuum bath, haul-off and cut- ting saw. Molecor manufactures itself and not only for its own production lines, the line compo- nents for the second process step, which include a heating station, the blowing station and a cooling unit. “Of course we make use of our own experience in pipe pro- duction for continuous optimiza- tion of our machine technology,” Dolores Herran highlights a fea- ture providing added value for customers. battenfeld-cincinnati and Mole- cor have now sold jointly more than 15 lines for producing PVC-O pipes world-wide, to destinations such as India, Kazakstan, Malay- sia, and Australia. “Our success proves us right: the ideally coor- dinated complete extrusion lines combined with Molecor technol- ogy offer pipe manufacturers a clear competitive edge,” Gernot Dorn sums up. Twin screw extruder twinEx for the extrusion of O-PVC pipes battenfeld-cincinnati Austria GmbH (Vienna, Austria) www.battenfeld-cincinnati.com Molecor Tecnologia SL (Loeches-Madrid, Spain) https: /molecor.com/en