Pinhole devices are used in conjunction with film blowing units, bag manufacturing machines or wrapping units. Perforated films are mainly used for shrink packaging and in addition, wherever the film is intended to provide air compensation. The pinhole devices consist of a roller equipped with needles and a low-wear counter-pressure brush roller. The brush roller (Ø 65 mm) can be raised manually from the needle roller.

The normal version of the needle roller (Ø 50 mm) consists of a base axle and two screw-fitted carrier shells for the needles. The edging of the carrier shell and the corresponding fixing holes cannot be equipped with needles.

Equipment of the carrier shells with a special customer-specific needle pattern is possible. Minor deviations in the predetermined needle pattern cannot be completely avoided however owing to the manual manufacturing method. The carrier shells are replaceable and can be redressed at the factory if desired. The needle and brush rollers are not driven; the self-driven film is transported through the perforating station.

The brush roller presses the film on to the needle base and the contact pressure exerted by the own weight of the roller is reinforced by spring resistance. The needles therefore perforate the film. The needle and brush rollers are driven by the own movement of the film. The needles remerge from the film by the rotation of the rollers and the film is perforated. The input and output angle of the film to the needle roller should be approx. 15° for optimum perforation results.