Pumping thermally sensitive rigid PVC has a long history of process-related challenges. With the launch of the extrex⁶ EC at Fakuma 2026, the MAAG Group is introducing an optimized gear pump that eliminates dead spaces, reduces the load on the extruder, and facilitates the processing of recycled material.
In extrusion processes, rigid polyvinyl chloride (PVC-U) is considered one of the most difficult media to pump continuously. Conventional gear pumps have internal gaps and D-shaped bearings where the medium can remain for too long. With PVC, this prolonged residence time inevitably leads to degradation, deposits, and burning of the material.
Swiss engineering firm MAAG Group has designed the internal flow geometry of the extrex⁶ EC in such a way that dead spaces and gaps have been eliminated. This prevents the polymer from accumulating.
Key benefits of the system:
Practical tests carried out by the REHAU Group show that the pump’s volumetric accuracy minimizes pressure fluctuations at the die head, even when processing heterogeneous batches of recycled material.
As the thermal stress on the melt is lower, discoloration is prevented, and the use of expensive thermal stabilizers in the formulation can be reduced or eliminated. This makes it economically viable to replace virgin PVC (virgin material) with regrind and recyclate.
Following a trial phase between 2022 and 2025, the system is now operational at one of REHAU’s production sites in Spain, after which it will be gradually rolled out across the global production network.
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