Abstract: A pressure relief device for an internally pressurized container. The device is imperforate, forms an integral part of the container surface, and has a concave annular outer area integrally joined to an inwardly protruding circular central area by an annular intermediate area. These areas have different thicknesses resulting exclusively from the device having been drawn from a metal blank. The juncture of the annular outer and intermediate areas forms a first circular line of strain hardened material having a reduced thickness and increased hardness and strength as compared to the material thickness, hardness and strength of the annular outer area. The cross sectional configuration of the device is such that upon eversion thereof occasioned by an over-pressurization of the container contents, the material along the first circular line will fracture at at least one location, thereby allowing the container contents to escape therethrough.

Abstract: A pressure relief device for a metal container having a generally cylindrical side wall and being of the type adapted to contain fluids under pressure. The device includes a concave closure element circumferentially joined to one end of the container side wall. The closure element is deep drawn of tempered steel, with a generally convex tab member integrally formed in a central area thereof. The tab member is partially circumscribed by a weakened line of reduced material thickness, and the closure element has a structural integrity which reacts to an overpressurization of the fluid in the container by undergoing a partial eversion which initiates a fracture along the weakened line accompanied by an outward deflection of the tab member, thereby permitting the overpressurized fluid contents to escape through the fracture.

Abstract: A pressure release device for an internally pressurized fluid container has a dome-shaped inwardly concave closure element circumferentially joined to one end of the tubular container side wall. The closure element is deep drawn of tempered steel, with a circular central area spaced from an annular outer area by an annular intermediate area traversed by radially extending L/u/ ders Lines. A tab member is located in the central area. The tab member is partially circumscribed by a single weakened circular line of reduced material thickness, with the ends of the line being separated by a connecting area of substantially undisturbed material thickness and strength.

Abstract: A pressure relief device is disclosed for a container having a cylindrical side wall which is closed at one end by an internally concave bottom wall. The device comprises an externally protruding first cup formed as an impression in the container bottom wall. The first cup has a first circular wall which is joined at one end to the container bottom wall and which is closed at the opposite end by a first base portion; A tab member is located in the first base portion. The tab member is partially circumscribed by a line of reduced material thickness along which the first base portion is adapted to separate in response to an overpressurization of the container contents, thus freeing the tab member for outward deflection to provide an outlet through which the contents may escape. A second element having a second circular wall is forcibly received within the first circular wall of the first cup.