Closed-head drum with liner, and method for producing the same

A closed-head drum from thermoplastic plastics material, having a liner composed of a thin-walled plastics material film, comprising a cylindrical drum wall, a disk-shaped lower base, and a disk-shaped upper base in which two bung connectors, which are closable by means of a bung closure, are disposed, wherein one bung connector is configured as a filling and retrieval bung connector, and another bung connector is configured as a ventilation and aeration bung connector, one respective filling and retrieval liner connector and one ventilation and aeration liner connector of the liner each fastened in said filling and retrieval bung connector and ventilation and aeration bung connector, wherein the bung closure for the ventilation and aeration bung connector is configured in multiple parts and has at least one lower adapter ring and an upper union or ring nut, each of which is provided with one centric passage opening, and a centric bung plug, which is screw-fitted into the centric passage opening of the adapter ring, wherein the adapter ring is fixedly welded to an upper end of the ventilation and aeration bung connector of the liner, and by way of a flange ring of a screw-fitted ring nut is fixed in the ventilation and aeration bung connector of the closed-head drum,

• characterized by the following features:
• both bung connectors are configured as identically-sized standardized 2″ bung connectors having an internal thread (BCS 70×6 closure) and a sealing bed lying therebelow;
• the bung closure for the filling and retrieval bung connector is configured as a commercially available standardized 2″ bung plug having an external thread (BCS 70×6 closure) and a sealing ring lying therebelow, said sealing ring sealing against the sealing bed in the filling and retrieval bung connector;
• the filling and retrieval bung connector, below the internal thread at a tightest passage point of said filling and retrieval bung connector in the connector neck, has a smoothed, annular flat weld bed inner surface to which an upper end of the filling and retrieval liner connector of the liner is fixedly welded;
• the bung plug screw-fitted into the centric passage opening of the adapter ring is configured as a commercially available standardized ¾″ bung plug having an external thread and the sealing ring lying therebelow;
• the flange ring, engaged across by the screw-fitted ring nut, of the adapter ring, on a lower side thereof, on an external periphery has an encircling sealing ring, and seals a drum interior against the sealing bed below the internal thread in the ventilation and aeration bung connector.