New membrane plate improves bubble control and improves film quality

A key factor in the quality of the blown film is to ensure the control of the bubble from the die to the nip roller. The more control the operator takes in directing the bubble upward into the cradle and into the nip gap, the less chance of wrinkles, scratches or other damage to the film. Most towers hold the film before entering the nip roller either with a roller set or with an air plate. U.S. Battenfeld Gloucester Engineering combines the best features of these two systems with a unique and innovative approach to guarantee bubble control and film quality: while using non-contact air plates and composites Roller RollAir Scaffold.

RollAir herringbone provides stable control and film quality regardless of film thickness or surface properties. It works equally well for thin films, clear films, coextruded films, stretched films, and adhesive films. It combines the best characteristics of both the roller set and the air plate. The system uses two air floating components under a set of composite rolls. The air plate mounted on the lower shelf has hundreds of holes through which the air pressure floats. Providing air floats in this area, the bubble does not have to be traditionally in contact with the roller set. This eliminates scratches on the film.

The film then travels through the composite roll set, which draws the film bubble slightly in the machine direction as the bubble is directed toward the nip roll. As a result, all of the air sheet herringbone systems are used in comparison, and the film enters the nip roller in a more straight direction. This eliminates the potential for trapping air behind the bubble and improves the flat-fold quality. The composite roller is only half the weight of the aluminum roller, and its inertia is only half that of the aluminum roller, and it does not transfer the heat from the film like the aluminum roller.

Battenfeld Gloucester Engineering installed a RollAir herringbone at its technical center in Gloucester. The size of this herringbone frame is 1879.6 mm in width and 4064 mm in length. And they can be made in a wide variety of sizes and with different engineering designs to suit any Battenfeld Gloucester Engineering blown film line. Modifications to the production lines of other manufacturers can also be discussed.