The COEX BUBBLE plant represents the state-of-the-art plant of the Torninova production range. Equipped with all of the most sophisticated technologies for air bubble film production, it ensures simplified production to the customer, thanks to the fully automated co-extrusion process, to obtain a film with air-barrier effect that keeps the air inside the bubble for longer. The main advantages of this film are as follows:

Improved protection (cushioning) capacity in comparison to a thicker mono-extruded air bubble film of higher grammage: the co-extruded film offers greater air retention (thanks to the internal layer of PA6) and therefore ensures effective long-term cushioning performances from packaging to final delivery. It also means that each bubble is extra resistant and therefore provides extra protection for the goods packed.

Improved protection with a thinner plastic film: results in greater performance with less raw material consumption.

Reusable: thanks to the long-lasting protective performances, the product can be used many times.

Recyclable: the co-extruded bubble film can be recycled with other polyethylene materials.

A 35 g/m˛ air bubble film produced by co-extrusion process can be compared with a 55 g/m˛ mono-extrusion air bubble film, in terms of resistance, resulting in a saving of 30% of the production cost.

Mainly, the COEX BUBBLE plant consists of three extruders: one for the PE layer, one for the PA6 layer and the third for the TIE layer between PE and PA6. These three extruders, by means of the latest generation adjustable geometry feed-blocks, enable the production of the special co-extruded air bubble films, each with ABCBA structure. The co-extrusion process can be easily understood through the following layout:

 

Essentially, each one of the 2 films required to create the bubble (base layer film and bubble layer film) consists internally of 5 very thin layers of 3 different materials. By  analyzing these films through a microscope, we see an internal structure as follows:

 

Once these films are thermoformed, to obtain the air bubble film, the PA6 layer – the layer that remains inside the layering – is the element that characterizes the final product, constituting an air barrier that prevents any air loss from the bubble, considerably increasing the lifespan of the product, in addition to granting greater cushioning. 
 

The COEX BUBBLE plant has got the following features:

Extruders with AC axis mounted alternating current motors and with universal screws in wear-resistant steel, featuring modular profiles with double barrier thread, in different diameters according to the level of production requested. Each extruder is equipped with a filter and a gear pump powered by gimbals and inverter and feedback loop controlled engine. The gear pump, via PID controller, automatically adjusts the speed of the extruder according both to the extent required by the formula of production and to the extrusion pressure required.

Two separate flat dies, for greater control and management of the produced films, constructed in steel with adjustable output.  The variable geometry of the feed-block grants an even inner layer of polyamide (PA6) across the entire width of the film and a thickness of less than 0.5 microns.

  

Gravimetric batcher ingredients for a more accurate and automated management of the granules to be extruded.  

  

Central group mounted on rails and rack rods, allowing automated movement during the production phase until the pause phase. The forming cylinder is mounted on a mobile structure (motorized and programmable by PLC) on both axes for adjusting the entry of the materials from the flat heads and for its rapid interchangeability.

  

Automatic thickness control: thanks to the gear pumps of each extruder and the encoder on the forming cylinder, the operator can determine the grammage to be produced directly from the control panel in automatic mode.

  

Control panel managed by PLC, complete with full supervisory software operated via a touch screen that allows programming and operation of the entire plant. Production management occurs through formulas that the operator can customize depending on the percentages of co-extrusion requested and the production speed.

  

The forming cylinder is thermoregulated by a water unit in order to maintain a more constant temperature during the production process.

  

Produced film width from 1,000 mm to 2,500 mm or more on request.

The plant can be equipped (also after installation, thanks to its modularity) with several accessories:

Moulder cylinder with bubble in different diameters.

Perforation unit with brushless motor.

Teflon casting cylinder thermoregulated by oil thermal power units for improved control of the thickness of the films produced.

Third and fourth layer units that enable in-line lamination of one or two sides of air bubble film, eliminating further operations.

Trimming unit and trims recycling, in keeping with in-line recovery through force hopper supply system.

FAST LOADING system on the rewinder that enables the automatic unloading of the produced roll with glue closing system and the loading of the new cardboard core with an application of “hot-melt” glue.   

The machines are fully customizable. Contact us to design the most suitable plant for your production and market needs.