An apparatus and method for controlling the flow of molten material from a melt container. The apparatus includes a tubular insert sized for insertion into a tap hole formed in a sidewall of the melt container and a rod receivable within the insert. A cooling device is provided to cool the rod to a temperature below the temperature of the molten material. The rod is axially movable within the insert between a first position wherein the rod is positioned within the tubular insert for cooling a portion of the molten material located at the first end of the insert to form a plug and stop the flow of molten material through the passageway, and a second position wherein the rod is spaced from the first end of the insert to allow the plug to melt and start the flow of molten material through the passageway. A method for trapping gases emitted during the melt and tapping processes is also disclosed.