Overturning device for overturning molten material in a melt channel and purging method

A method for performing a purge process in an extrusion device, comprising the following steps:

• Insertion of the molten material into a melt inlet of an overturning device for overturning a molten material in a melt channel comprising a melt inlet and a melt outlet, wherein between the melt inlet and the melt outlet at least a melt guiding means is assembled for a rearrangement of the molten materials from the centre of the melt inlet to the edge of the melt outlet and for a rearrangement of the molten material from the edge of the melt inlet into the centre of the melt outlet, wherein the at least one melt guiding means comprises a separation section with a first separation channel and a second separation channel, wherein in front of the separation section a divisional section for dividing the molten material to the separation channels and after the separation section a combination section from merging the molten material from the separation channels is assembled, wherein the combination section is configured for a central merging of the edge sections of the molten material,
• Rearrangement of molten material from the centre of the melt inlet to the edge of the melt outlet of the overturning device and
• Rearrangement of molten material from the edge of the melt inlet into the centre of the melt outlet,
• wherein a recombination of separation streams of the molten material occurs by a complete or mainly complete rearrangement.