| 摘要 |
The lid (1), injection-moulded for example from polyethylene, for a wide-necked drum of plastic has an outer rim (4) surrounding the drum neck (3) and an inner rim (5) extending into the drum neck. Lid outer rim (4) and lid inner rim (5) form an annular space (7), from the base of which an annular web (8) projects axially. For manufacturing the lid seal (13), the annular space (7) is exposed to an open flame to activate the surface of the annular space. Subsequently the sealing material, preferably polyurethane, is injected with a foaming machine into the base of the annular space (7), and then the lid (1) is vibrated to degas the seal (13). The sealing material consisting preferably of foamed polyurethane contains a release agent with long-term effect. …<IMAGE>… |
