Abstract: A valve insert (40) is adapted to be removably mounted as a unit on a cylinder valve (41) to selectively enable a flow of fluid therethrough when a male coupling section (52) is inserted into the outlet of the cylinder valve. The improved insert includes a tubular body (55), a valve member (58) mounted for sealed sliding movement relative to the body, biasing means (97) and a docking member (59) mounted on the valve element and adapted to engage the nose of the male section. When the male section engages the insert and displaces a sealing cushion (80) off its seat (72), the pressure of fluid will urge the valve element (58) into tighter sealed engagement with the male section.

Abstract: An improved coupling device (e.g., 134) has a first section (e.g., 135), a second section (e.g., 136), and a sleeve member (e.g., 138) mounted on one of the coupling sections and arranged to selectively engage the other coupling section. The sleeve member is provided with a weakened portion (e.g., 156). The weakened portion is formed of a suitable material and is so configured and arranged as to permit the two coupling sections to be physically separated from one another through thermally-induced flexural deformation of the weakened portion, without rotation of the sleeve member relative to either section, when the temperature of the weakened portion is greater than about 200.degree. F. but less than about 300.degree. F., and preferably about 266.degree. F.

Abstract: A valve insert (40) is adapted to be removably mounted as a unit on a cylinder valve (41) to selectively enable a flow of fluid therethrough when a male coupling section (52) is inserted into the outlet of the cylinder valve. The improved insert includes a tubular body (55), a valve member (58) mounted for sealed sliding movement relative to the body, biasing means (97) and a docking member (59) mounted on the valve element and adapted to engage the nose of the male section. When the male section engages the insert and displaces a sealing cushion (80) off its seat (72), the pressure of fluid will urge the valve element (58) into tighter sealed engagement with the male section.