Abstract: A method, apparatus and system for testing the integrity of a container sealed by means of a closure comprising a resilient sealing element and a cup-like cap having a top and a depending skirt compressing the sealing element over the discharge opening in the container. The invention consists in measuring the change in thickness of the resilient sealing element resulting from compression of the sealing element on the container and comparing the change in thickness or a value determined therefrom to a predetermined standard known to indicate sufficient compression to provide an acceptable seal. Resilient sealing element thickness is measured by apparatus including a sensing head having an anvil engageable with the closure mounted on an actuator member of a dial indicator. A face of the anvil engages the top of the cap along a circular line adjacent of the corner radius at its juncture to the top of the cap.

Abstract: A container closure assembly for a container comprising an outer cap of generally cup-like form having a top and a skirt depending from the outer peripheral edge of the top and means for detachably securing the same over the opening in a container, an annular pocket formed in the skirt of the outer cap adjacent said top and a liner assembly consisting of at least a disc-like core of a resilient material, a shell for the core having a portion confronting the inside of the top of the outer cap and a locking portion to hold the core in said shell, said shell being of a predetermined dimension to permit limited axial movement in the pocket in the outer cap and anti-friction means between the shell and outer cap to permit relative rotation between the outer cap and the liner assembly.