Abstract: A procedure and device for longitudinal sealing and cutting of a film web, in particular a foil tube, in which the film web shows at least two layers of film, made of thermoplastic synthetic material, and in which the film web is sealed and cut in a continuous process by leading it through the device, in which the film first contacts the heating element in order to seal the two film layers by welding, in order to cut this sealed seam in the middle of the seam by guiding the film web over the cutting element, which dividends the sealed seam into at least two partial film tubes.

Abstract: A procedure and device for longitudinal sealing and cutting of a film web, in particular a foil tube, in which the film web shows at least two layers of film, made of thermoplastic synthetic material, and in which the film web is sealed and cut in a continuous process by leading it through the device, in which the film first contacts the heating element in order to seal the two film layers by welding, in order to cut this sealed seam in the middle of the seam by guiding the film web over the cutting element, which dividends the sealed seam into at least two partial film tubes.

Abstract: An improved blown film extrusion apparatus is provided. The apparatus includes an annular die for extruding a film tube. At least one tube position transducer is provided and located adjacent to the extruded film tube. The tube position transducer transmits interrogating pulses to the extruded film tube and produces a position signal corresponding to a detected position under the extruded film tube. A bubble position control system is provided for receiving and processing the position signal. A valve is provided for varying a quantity of air within the extruded film tube in response to the bubble position control means. This urges the extruded film tube to a desired position. The apparatus further includes a collapsing frame assembly for receiving the extruded film tube and collapsing it. The collapsing frame assembly includes several frame boards. Typically, two opposing main boards and two opposing side boards are provided.

Abstract: A blown film extrusion apparatus and method is provided including a tube position transducer transmits interrogating pulses to the extruded film tube and produces a position signal corresponding to a detected position under the extruded film tube. A bubble position control system is provided for receiving and processing the position signal. The apparatus further includes a collapsing frame assembly for receiving the extruded film tube and collapsing it. A position transducer is provided for detecting the position of at least one of the frame boards. At least one board position actuator is provided for adjusting the position of at least one of the boards. A board control system is provided for receiving the board position information from the board position transducer and for providing control signals to the board position actuator to maintain at least one of the boards in a predetermined position.