Abstract: A gas leakage detector includes a housing, an inlet coupling, internal fluid flow path and an outlet coupling enabling the housing to be installed and coupled permanently in-line with a gas supply line. The housing includes a cutoff valve, a gas pressure indicator coupling valve, a detachable gas pressure indicator, and a charging gas source coupling enabling a one way flow of optional use charging gas to enter the housing downstream of the valve and to pass into and through the gas supply line. Existing line pressure or charging gas pressure is monitored at the indicator to indicate the presence of any leaks downstream of the valve. The indicator may be attached to the coupling valve on the housing or to the external charging gas source.

Abstract: A gas actuated valve system includes a gas switch disposed in a primary gas circuit upstream of a gas driven actuator. The switch is movable to an open position when a pilot gas is supplied under pressure to the gas switch through a pilot circuit, and is movable to a closed position when the pilot pressure is released. A seismic valve coupled to the pilot circuit senses seismic activity and releases pilot gas pressure, thus moving the gas switch to the closed position, when seismic activity is detected.

Abstract: An air actuated valve system for shutting off fluid flow in a fluid conduit includes a seismic valve disposed in a seismic air circuit which is coupled to a primary air circuit. The primary air circuit delivers air at a high pressure to an air driven actuator which maintains a shut off valve in a fluid conduit in an open position. The high air pressure flows through an air switch which is operationally open and coupled to the seismic air circuit such that when the seismic valve is closed a pilot air pressure is prevented from flowing to the air switch. In the absence of the pilot air pressure, air pressure is bled from the air switch, causing the air switch to move from an open to a closed position, thus preventing air from flowing to the air actuator.

Abstract: A gas leakage detector includes a housing, an inlet coupling, internal fluid flow path and an outlet coupling enabling the housing to be installed and coupled permanently in-line with a gas supply line. The housing includes a cutoff valve, a gas pressure indicator and a charging gas source coupling enabling a one way flow of optional use charging gas to enter the housing downstream of the valve and to pass into and through the gas supply line. Existing line pressure or charging gas pressure is monitored at the indicator to indicate the presence of any leaks downstream of the valve. The system may be used to continuously monitor gas pressure.

Abstract: An air actuated valve system for shutting off fluid flow in a fluid conduit includes a seismic valve disposed in a seismic air circuit which is coupled to a primary air circuit. The primary air circuit delivers air at a high pressure to an air driven actuator which maintains a shut off valve in a fluid conduit in an open position. The high air pressure flows through an air switch which is operationally open and coupled to the seismic air circuit such that when the seismic valve is closed a pilot air pressure is prevented from flowing to the air switch. In the absence of the pilot air pressure, air pressure is bled from the air switch, causing the air switch to move from an open to a closed position, thus preventing air from flowing to the air actuator.

Abstract: A shock actuated shut-off valve for fluid flow lines is provided which includes a valve housing having a central chamber in communication with inlet and outlet conduits and with a hollow, outwardly enclosed stowage arm in upward, substantially plumb communication with the central chamber. A valve element having a longitudinal aperture incorporating non-occlusive abutment means is releasably supported in the stowage arm for vibratory displacement to and sealing engagement with the central chamber. An inner closure is sealingly disposed in the stowage arm above the valve element. A tether slidably and sealingly extends through an aperture in the inner closure and extends, in spaced relationship, through the aperture in the releasably supported valve element, with the lower end of the tether incorporating a lift member disposed, in a non-obstructive static position, below the abutment means.