Extrusion: MDO Stretches Film-Performance Limits
Systems rely on infrared heaters inside the cylinder.
Machine Direction Orientation (MDO) equipment from Colines features a patented heating system with infrared ray heaters inside the cylinder, so the orientation takes place without any temperature dissipation, which is a common fault found in standard cylinders. This reportedly minimizes the energy consumption as well. Moreover, the sensors detect the temperature directly on the film, resulting in a more accurate reading of the data. The IR heating system also guarantees reaching the operating temperature much faster than oil and water systems do, which means that IR heating system dramatically reduces scrap during line startup.
A further benefit, thanks to the possibility of adjusting the position, speed and temperature of the cylinders independently, is the significant reduction of the neck-in. The infrared eliminates the risk of potential oil and water leakage. It represents an enormous advantage as far as environmental sustainability goes.
Tests run by Colines at its lab in Italy show that a 15-18 micron MDO PP film can replace a 25-40 micron cast PP film. Naturally, this is achievable using specific film recipes and depends on the final applications of the film.
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