Extrusion

Extrusion welding of HDPE is a typical welding procedure. Before welding begins, the surface of the polyethylene must be ground down, to expose virgin the HDPE. A spark test wire may be placed in the groove; this will be used to later test the quality of the weld. Now the extrusion gun is set in place and it begins to extrude a bead of molten polyethylene. Super heated air is forced out the nozzle, melting the surface. Molten polyethylene is then forced out of the extruder, where it bonds with the surface. A spark tester is used to test the integrity of the weld seam. The extrusion weld creates a molecular bond between the sections of polyethylene.