Overpressure protective device and method for passively blocking gas flow at a pressure setpoint

A passive overpressure protective device, comprising:

• a valve body having a first valve port, a second valve port, an interior passage communicating between the first and second valve ports, and a valve having an open position that permits communication of pressure via the interior passage and a closed position that blocks communication of pressure via the interior passage;
• a valve stem that is mechanically coupled to the valve and that is configured for linear translation distal from a proximal to the valve body;
• and
• a bellows having a proximal end fixed with respect to the valve body and a distal end mechanically coupled to the valve stem, such that movement of the bellows responsive to an ambient pressure change passively linearly translates the valve stem to operate the valve.

A method of providing passive overpressure protection, the method comprising:

• coupling to a pressure line a passive overpressure protective device including:
• a valve body having a first valve port, a second valve port, an interior passage communicating between the first and second valve ports, and a valve having open and closed positions;
• a valve stem mechanically coupled to the valve;
• and
• a bellows mechanically coupled to the valve stem, such that movement of the bellows responsive to an ambient pressure change passively moves the valve stem to operate the valve, wherein the coupling includes coupling the pressure line to the second valve port;
• based on an ambient pressure change acting on the bellows, the bellows moving the valve stem to cause the valve to operate.