Overpressure protective device and method for passively blocking gas flow at a pressure setpoint
AssigneeWeed Instrument Company, Inc.
InventorTaylor M. Campbell
Life of this patent
Estimating the term…
Abstract
An overpressure protective device for passively blocking flow of gas at a selected pressure setpoint includes a valve, a valve stem, and vacuum-filled bellows coupled to the valve stem. The vacuum-filled bellows are configured such that expansion and/or contraction of the bellows as a result of pressure changes present at the valve are harnessed to passively move the valve stem to operate the valve and block pressures higher than a preconfigured pressure setpoint. If the process pressure drops below the pressure setpoint, the overpressure protective device operates the valve to again permit flow of pressurized gas through the valve.
Claims22
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 condition in which pressure is communicated between the first and second valve ports and a closed condition in which pressure is not communicated between the first and second valve ports;
- a valve stem mechanically coupled to the valve;
- and
- a vacuum-filled 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 change the valve between the open condition and the closed condition.
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 condition that permits communication of pressure via the interior passage and a closed condition 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 and proximal to the valve body;
- and
- a vacuum-filled 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 change the valve between the open condition and the closed condition.
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 an open condition in which pressure is communicated between the first and second valve ports and a closed condition in which pressure is not communicated between the first and second valve ports;
- a valve stem mechanically coupled to the valve;
- and
- a vacuum-filled 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 change the valve from the open condition to the closed condition, 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 change the valve between the open condition and the closed condition.
A passive overpressure protective device, consisting essentially of:
- 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 condition in which pressure is communicated between the first and second valve ports and a closed condition in which pressure is not communicated between the first and second valve ports;
- a valve stem mechanically coupled to the valve and configured for linear translation proximal to and distal from the valve body;
- at least one vacuum-filled 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 change the valve between the open condition and the closed condition;
- a coupling member that mechanically couples the valve stem and the bellows;
- and
- a friction collar configured to set an initial linear position of the valve stem corresponding to a pressure setpoint at which the valve stem changes the valve to the closed condition.
Dependencies are inferred from the claim text.