Abstract: A closure system including a polymeric split ring clamp and a polymeric lid for a polymeric drum. To maintain the integrity of the closure, the lid rim region is formed having an annular restraining notch which cooperates with twist inhibiting blocking components formed within the interior of a cooperating inwardly opening polymeric split ring clamp. The blocking component may be provided as a sequence of regularly spaced block-like protuberances located within the inward upwardly disposed region of the ring clamp. A secondary closure arrangement is provided with the split ring clamp which receives a polymeric banding strap to prevent one end of the split ring from disengaging with an associated pivot arm. When the split ring clamp is in a fully open or pre-clamping mode orientation, a capture groove is formed with the ring pivot shaft formed at one end of the split ring clamp.

Abstract: A molded lid having an intermediate region configured as a sequence of waves, each of curved cross-section forming successively occurring crests and troughs, and exhibiting amplitudes increasing in value from the lid center toward the rim. The waves terminate at a ring band which is located to slide in adjacency with the inwardly disposed side of a plastic drum. The lid is provided with a polymeric gasket which is retained in position by a retainer band which is insertable in sliding compressive engagement within a retainer cavity.

Abstract: A split ring clamp for retaining a lid upon an enclosure such as a plastic or fibrous drum is provided which is formed entirely of polymeric material such as a high molecular weight, high density polyethylene copolymer. The assemblage includes two parts, a channel-form split ring and a pivot arm joining the two ends of the split ring together over the rim structure of a container. One end of the ring supports an integrally formed pivot shaft receiving notch as well as an outwardly extending toe with a rearwardly disposed contact surface. The opposite side of the ring is formed having a receiver channel within which there is provided an inwardly depending toe with a rearwardly facing contact surface. The pivot arm is formed having a transversely disposed arm pivot shaft and a ring pivot shaft receiving notch having a shaft access opening which is outwardly disposed and extends to a shaft bearing surface. Such an arrangement permits a more thin profile for the ring and pivot arm assembly.