Bung

A bung, stopper or cork is a truncated cylindrical or conical closure to seal a container, such as a bottle, tube or barrel. Unlike a lid, which encloses a container from the outside without displacing the inner volume, a bung is partially inserted inside the container to act as a seal. A bung, stopper or cork is a truncated cylindrical or conical closure to seal a container, such as a bottle, tube or barrel. Unlike a lid, which encloses a container from the outside without displacing the inner volume, a bung is partially inserted inside the container to act as a seal. A bung can be defined as 'a plug or closure used to close an opening in a drum or barrel. Called a plug when referring to a steel drum closure.' A glass stopper is often called a 'ground glass joint' (or 'joint taper'), a rubber stopper is sometimes called a 'rubber bung', and a cork stopper is called simply a 'cork'. Bung stoppers used for wine bottles are referred to as 'corks', even when made from another material. A common every-day example of a bung is the cork of a wine bottle. Bungs are used to seal the bunghole of barrels. Other bungs, particularly those used in chemical barrels, may be made of metal and be screwed into place via threading.