Patent ID: 7703472

Claim:
A gas flow isolation device for isolating the flow of gas from one module into one or more other modules joined to said one module through one or more common headers, said gas flow isolation device including: an inlet passage and an outlet passage including a flow restricting orifice through which gas passes to reduce the pressure of gas downstream of said orifice, said inlet passage being adapted to communicate with an outlet from said one module to receive a flow of gas from said one module, and said outlet passage communicating with said inlet passage for receiving said flow of gas and directing said gas out of said isolation device; a module isolation valve movable from an opened condition to a closed condition to prevent the flow of gas from the inlet passage to the outlet passage when the pressure of the gas in the isolation device exceeds a predetermined level, said module isolation valve including: a rupture disk having a first face and a second face, said first face being in flow communication with the outlet from said one module when the outlet of said one module is placed in flow communication with the inlet passage of the isolation device and the module isolation valve is in an opened condition permitting the flow of gas from the inlet passage to the outlet passage of said isolation device, said gas engaging and applying pressure to said first face of the rupture disk, said second face of the rupture disk being in flow communication with a chamber maintained at a desired low pressure by being in flow communication with the flow of gas downstream of said flow restriction oriface, said rupture disk rupturing when a predetermined pressure differential occurs across said rupture disk; a valve seat between said inlet passage and said outlet passage; a valve stem having opposed first and second ends, said first end being mechanically linked with the first face of said rupture disk and the second end being coupled to a valve member, said valve member being spaced from the valve seat when the first end of the valve stem is mechanically linked with the rupture disk to permit the flow of gas from the inlet passage to the outlet passage and also to permit the flow of gas into engagement with the first face of the rupture disk when the inlet passage is placed in flow communication with the outlet from said one module; whereby said rupture disk will rupture upon a predetermined pressure differential occurring across the rupture disk to cause the valve member to seat against the valve seat and terminate the flow of gas from the inlet passage to the outlet passage and also through the rupture disk.