Krauss Maffei Extrusion of Munich Germany, a world leader in plastics processing machinery have recently completed a project for a manufacturer in Far East Asia to develop a machine that can extrude winding core tubes that will be used for winding various types of plastic films.
The advantages of using plastic winding tubes compared to paper or cardboard include the fact they are resistant to moisture, are reusable and compared to steel tubes - they are not subject to corrosion.
A major challenge in the project was the exceptionally tight tolerance ranges, within which the tubes had to be produced. Other challenges included the need for high melt homogeneity and stable temperature profiles together with effective degassing/extraction during the extrusion process.
Krauss Maffei were able to custom build a 36D KME 90-36 B/V single screw extrusion machine that could process HDPE and also HIPS and the amorphous ABS. They added a special venting port in the barrel, which allowed for the release of moisture during the melting process. A special pipe head design (KM-RKW 33) and calibration were able to meet the critical tolerance requirements.