W&H 5 layer blownfilm line
|Machine||W&H 5 layer blownfilm line|
|Type of extruder||Blown|
|Number of layers||5|
|Diameter die||W&H Die 500 with Mulitcool|
|L/D ratio screw(s)||30D|
|Material & Min – Max thickness||Barrier film 10 – 200 mu|
|Max. film width||1420 mm|
|Max. output||380 kg/hour|
|Rewind manufacturer||Afex with Lenze Drive Retrofit incl. Safety Concept|
|Rewind type||Contact, Gab and LPC|
|Max. rewind reel diameter||1000 mm|
|Number & sizes airshafts for winder||5 pics, 3inch and 6inch|
|Type of screen changer||W&H, manuel system|
|Dosing unit||Main component with a few side components|
|Inline slitting||Yes, two up|
|Tower construction included||No|
|Special characteristics||5 layer barrier film|
W&H 5 layer
(Windmöller & Hölscher)
The W&H Group produces extruders, printing presses en converting machines. For more than 140 years W&H has been manufacturing converters for flexible packaging. They have sold over 5000 machines in more than 140 countries. This German based company has its plant in Lengerich.
Extrusion in the flexible packaging industry can roughly be devided in three kinds of extrusion: blown film extrusion lines, cast film extrusion lines and BOPP extrusion lines.
Blown Film Extrusion
Blown film extrusion is the most common technology to produce plastic film. Blown film extrusion is typically carried out upwards vertically.
Film is made out of polymer material. These polymeres are generally in the form of granulate. This material is melted and then forced or extruded through a die. Air is blwon thourgh a hole in the center of the die. This pressure causes a bubble. The bubble is a thin layer of film. The film is pulled upwards from the die to cool down and winded on the a roll.
Blown film extrusion exists in various layers, the more layers the thicker the film. The process with more layers is called coextrusion.