Krauss Maffei Extrusion of Munich Germany, a world leader in plastics machinery is now offering an increased level of wear resistance for all parallel and conical twin screw extruders. This is achieved by the application of a plasma powder arc welding process (PTA) that coats the top-root edges of counter rotating screws.
"By using the plasma powder arc welding process, we can minimize the naturally occuring adhesive wear in counter rotating twin screw extruders and therefore increase the machine service times significantly" said Dr. Liebhold, Head of Extrusion Technology at Krauss Maffei. "Software developed specially for this application permits continuous welding even with incline changes in the flights to be coated and welding of the runouts depending on the selected screw geometry."
The system is designed for machining processing screws with diamaters ranging between 43 and 184mm and with the addition of the optional tungsten-carbide reinforcement coating, the treatment can add between 12,000 and 20,000 operating hours to the machines compared to standard machines. Tungsten-carbide coatings are typically used for highly abrasive applications, such as the processing of natural fiber composites for decking profiles.
Screw technology is a critical `know-how` for Krauss Maffei who manufacture all their screws and barrels in-house at their Munich facility.
Krauss Maffei is represented in Oceania by HBM Plastics Technologies.