Hot Air Sealer

The Hot Air Continuous Plastic Seam Sealers are a patented new concept that can be conveniently installed on virtually any machine that requires perfect heat sealing of plastic films, either intermittent or continuous.

The Model HLS-170 D has a heating zone of 170mm.
The Model HLS-220 D has a heating zone of 220mm.
The Model HLS-220 D (LE) has a heating zone of 220mm
with a cooling zone and larger housing for use at higher temperatures.

These unique sealers are mounted with a narrow gap between the sealer and the back-up strip on the forming tube or table. The work pieces to be sealed must be guided through the gap where they are heated by temperature controlled hot air. The air is introduced under pressure to heat the plastic films and concurrently force them together against the back-up strip. Typical sealing speed is 30 ft /min. for two layers of 2mil polyethylene film.

The Hot Air is heated as it passes through a high response, precisely controlled temperature heating tube and impinges on the film as it is passed through. If the air supply is interrupted the temperature controller will automatically compensate to avoid overheating the system. During intermittent operation the air supply control valve (Customer supplied) must be set to shut down when the film is no longer advancing. At Start-up the temperature rise time for the heater from ambient to set-point is only two to three seconds.

The Hot Air Sealing Unit is usually mounted on a bag forming machine close to the forming tube in place of the sealing bar. Best results are obtained by passing the film layers over a raised back-up strip on the forming tube in the heating area. This together with parallel alignment of the hold down device and carefully controlled spacing between the Hot Air Tube and the back-up strip on the Forming Tube, will produce consistently good seals.

During operation the Hot Air Tube is moved into close proximity of the film by the actuation of a control valve (Customer supplied). When not sealing the air source is allowed to move back to its initial position. When the machine stops, the heating system and the compressed-air supply must be switched off, the unit will then be withdrawn from the film to avoid overheating. For momentary stops or intermittent operation, interruption of the compressed air pressure will be sufficient.