Method for producing fused unplasticised polyvinyl chloride articles
AssigneeSteer Engineering Private Limited
InventorBabu Padmanabhan
Life of this patent
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Abstract
A method for producing a fused unplasticised polyvinyl chloride (UPVC) article (126) is provided. The method includes feeding an UPVC blend (103) into a co-rotating twin-screw extruder (100). The method further includes melting the UPVC blend (103) and conveying fused UPVC to an outlet (120) of the co-rotating twin-screw extruder (100). The method also includes collecting the fused UPVC from the outlet (120) at a rate of at least 100 kilograms/hour per litre of free volume (124) of the co-rotating twin-screw extruder (100).
Claims10
A method for producing a fused unplasticised polyvinyl chloride (UPVC) article (126), the method comprising:
- a) feeding an UPVC blend (103) into a co-rotating twin-screw extruder (100);
- b) melting the UPVC blend (103) and conveying fused UPVC to an outlet (120) of the co-rotating twin-screw extruder (100), wherein the co-rotating twin-screw extruder (100) includes at least a pair of melt forming elements (MFEs) (128) to melt the UPVC blend (103), and at least one MFE (128′) of the at least a pair of MFEs (128) includes a lead ‘L’ and includes at least one flight (129) helically formed thereon, the at least one flight (129) being continuous, and transforms at least once from a first non-integer lobe flight into a second non-integer lobe flight in a first longitudinal fraction of the lead ‘L’ and transforms back to the first non-integer lobe flight in a second longitudinal fraction of the lead ‘L’;
- and
- c) collecting the fused UPVC from the outlet (120) at a rate of at least 100 kilograms/hour per litre of free volume (124) of the co-rotating twin-screw extruder (100).
Dependencies are inferred from the claim text.