Abstract: A valve provides automatic switchover from a plurality of fluid pressure sources to a common outlet. The valve includes first and second spools respectively in first and second spool chambers, and each spool includes at least one sealing member carried thereon for selective sealing engagement with said first and second spool chambers. Fluid passageways transfer spool controlled fluid pressures between the first and second spool chambers. Each of said first and second spools are resiliently biased towards an open position, and fluid-biased towards a closed position. In an open position, the first and second spools are adapted to deliver pressurized fluid from an associated inlet port to an end chamber of the opposite spool chamber. In a closed position, the first and second spools are adapted via the at least one sealing member to inhibit delivery of pressurized fluid. A manifold assembly provides fluid communication to the common outlet.

Abstract: A valve provides automatic switchover from a plurality of fluid pressure sources to a common outlet. The valve includes first and second spools respectively in first and second spool chambers, and each spool includes at least one sealing member carried thereon for selective sealing engagement with said first and second spool chambers. Fluid passageways transfer spool controlled fluid pressures between the first and second spool chambers. Each of said first and second spools are resiliently biased towards an open position, and fluid-biased towards a closed position. In an open position, the first and second spools are adapted to deliver pressurized fluid from an associated inlet port to an end chamber of the opposite spool chamber. In a closed position, the first and second spools are adapted via the at least one sealing member to inhibit delivery of pressurized fluid. A manifold assembly provides fluid communication to the common outlet.

Abstract: A post valve yoke (35, 150) is operative to engage with a tank or cylinder (154) for placing the tank in fluid communication with a high pressure source of gas. The yoke includes a yoke body (148). The upper ends of the yoke body include a bore (160). A plunger (158) is operative to slide through the bore. The yoke body includes an opening (146) that is operative to receive a post valve (152) of the tank. The yoke is operative to urge the post valve with the plunger into sealed engagement with a passageway (144) in the lower end (174) of each yoke responsive to the movement of a lever arm (156) in pivoting connection with the plunger. A trigger lock (176) is operative to lock the lever arm in an engaged position to prevent the yoke from accidently disengaging with the post valve.

Abstract: A hydraulically operative post valve yoke mounting system. The system (10) includes one or more hydraulically operated yokes (41-44). Each yoke is operative to engage with a tank or cylinder (21-24) for placing the tanks in fluid communication with a high pressure source of gas (50). Each yoke includes a yoke body (140). The upper ends of each yoke body include a bore (116). A pin (104) is operative to slide through each bore. Each yoke body includes an opening (124) that is operative to receive a post valve (108) of a tank (110). Each yoke is operative to urge the post valve with the pin into sealed engagement with a passageway (142) in the lower end (114) of each yoke responsive to hydraulic fluid pressure. The hydraulic pressure may be supplied by a hydraulic pump (28) in fluid communication with hydraulic yoke.

Abstract: A post valve yoke (35, 150) is operative to engage with a tank or cylinder (154) for placing the tank in fluid communication with a high pressure source of gas. The yoke includes a yoke body (148). The upper ends of the yoke body include a bore (160). A plunger (158) is operative to slide through the bore. The yoke body includes an opening (146) that is operative to receive a post valve (152) of the tank. The yoke is operative to urge the post valve with the plunger into sealed engagement with a passageway (144) in the lower end (174) of each yoke responsive to the movement of a lever arm (156) in pivoting connection with the plunger. A trigger lock (176) is operative to lock the lever arm in an engaged position to prevent the yoke from accidently disengaging with the post valve.

Abstract: A hydraulically operative post valve yoke mounting system. The system (10) includes one or more hydraulically operated yokes (41-44). Each yoke is operative to engage with a tank or cylinder (21-24) for placing the tanks in fluid communication with a high pressure source of gas (50). Each yoke includes a yoke body (140). The upper ends of each yoke body include a bore (116). A pin (104) is operative to slide through each bore. Each yoke body includes an opening (124) that is operative to receive a post valve (108) of a tank (110). Each yoke is operative to urge the post valve with the pin into sealed engagement with a passageway (142) in the lower end (114) of each yoke responsive to hydraulic fluid pressure. The hydraulic pressure may be supplied by a hydraulic pump (28) in fluid communication with hydraulic yoke.

Abstract: A joint sealant composition that is compatible with Portland cement and with asphalt including, on a weight basis, from 57% to 75% of an aromatic petroleum tar boiling between 220.degree. C. and 650.degree. C., from 5% to 18% of an oil-soluble ground rubber, from 10% to 17% of inorganic filler, and from 3% to 6.5% PVC with the combined weight of PVC not exceeding 23% of the composition.