A tubular film blowing head is provided with one outer and one inner nozzle ring between which a ring chamber is formed extending in a conical or parabolic manner towards the circular nozzle gap and of which the inner nozzle ring, which is provided with a central bore for exchanging the pressurized air, is connected by means of a screw connection to a central cone piece of the blowing head. This central cone piece has a bore that is aligned to the central bore. In order to create a screw connection between the inner nozzle ring and the center cone piece that is firm and simple to produce, the inner nozzle ring is connected to the central cone piece by means of a threaded bolt penetrating the central bore of the nozzle ring and provided with an axial bore in that the threaded bolt is screwed into the bore of the cone piece, which is embodied as a threaded bore.
Tubular film die head for extruding single-layer or multi-layer film which has at least the following features: a substantially annular die gap, fastening elements which fix at least two components with respect to one another which together border areas bearing plastic melt within the tubular film die head, coolant-carrying elements. At least one part of the fastening elements is structured as coolant-carrying elements.
