Abstract: An apparatus for consecutively applying relief valves to a wrapper sheet fed to the apparatus comprises a chute defining a substantially vertically oriented inner track for receiving the valves in a series; a channel introducing the valves into the track; a retainer for alternatingly holding back and releasing a momentarily lowermost valve in the track; a valve advancing mechanism for intermittently causing the momentarily lowermost valve to clear the retainer; a welding device situated below the retainer adjacent the chute externally thereof for cyclically bonding a valve to the wrapper sheet; and a positioning device situated underneath the retainer for aligning the valve released by the retainer with the welding device. The wrapper sheet passes between the positioning device and the welding device. The apparatus also has a cutter for cyclically providing an opening in the wrapper sheet at the intended location of the valves.