Concentric-enveloping five-layer coextrusion blowhead for a blown film comprising five flow channel systems, wherein in each flow channel system, melt is guided in one of several layers of a blown film, each flow channel system comprising a group of spiral flow channels in a top of the blowhead and a main supply opening in a lower part of the die, wherein in the top of the die are provided six concentric shells circumferentially enveloping each other depending on their diameters, the central axis of the die using as the common center axis of these concentric shells, with each one A group of spiral flow channels is arranged between each two adjacent concentric shells, wherein five groups of spiral flow channels are arranged in order of size of their diameters from outside to inside, each group of s flow channels having each spiral flow channel provided with a starting point, wherein a total of 160 starting points are present in a die, with 32 starting points of a group of spiral flow channels in the circumferential direction uniformly arranged, with two adjacent starting points by an orientation angle of 11 , 25 °, characterized in that the lower part of the blowing head comprises four distribution discs, the lowest first distribution disc, the second distribution disc, the third distribution disc, the fourth distribution disc, which are circular in the horizontal projection view and arranged one above the other from bottom to top in that the six concentric sheaths arranged enveloping from outside to inside are arranged above the fourth distribution disk such that the central axis of the blow head is the common center axis of these four distributions That is, a horizontal interface between the lowermost first distribution disk and the second distribution disk serves as a first interface, a horizontal interface between the second distribution disk and the third distribution disk as a second interface, a horizontal interface between the third distribution disk and the fourth distribution disk as one third boundary surface is designated, and between the fourth distribution disc and the six concentric sheaths in each case an interface is formed, that the main supply openings of the respective flow channel systems at the edge of the first distribution disc are such that the main supply openings are lower than the first interface in the vertical direction, that the main supply port of the first flow channel system, the main supply port of the second flow channel system, the main supply port of the third flow channel system, the main supply port of the fourth flow channel system are arranged offset in each case in the counterclockwise direction by an orientation angle of 90 °, ...
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