This diploma thesis presents the investigation of a new extrusion conception for the manufacturing of PVC-U-profiles and -pipes. The production of PVC-U-profiles and -pipes is normally done with counter-rotating twin screw extruders. The disadvantage of this concept is the narrow range of the production, respectively throughput and material compounding, respectively product properties with one and the same extruder. The new conception uses a co-rotating twin screw extruder, followed by a gear pump. The function of the gear pump is to provide the necessary pressure build up for the system, whereas the co-rotating twin screw extruder is only responsible for the compounding and gelation of the material. The number of revolutions per minute of the gear pump sets the throughput rate of the system, whereas the number of revolutions of the co-rotating twin screw extruder provides the necessary shearing to crack and to distribute the PVC particles. With a comprehensive 48 channels data acquisition system all necessary process parameters were detected for setting up energy balances, and plotting pressure- and temperature-profiles. These investigations allowed the correlation between the process data and the product properties, as impact strength, yellowness index and gloss.