Control system with dynamic reference pressure
AssigneeFisher Controls International LLC
InventorMichel K. Lovell
Life of this patent
Estimating the term…
Abstract
A fluid control system is provided for controlling flow of a process fluid through a pipeline. The fluid control system can include a valve, one or more instruments in fluidic communication with the valve, and a pressurized chamber. In one example, the pressurized chamber contains the one or more instruments. In one example, the pressurized chamber has a dynamically variable pressure, which corresponds to a pressure in a downstream portion of the pipeline, such as a natural gas pipeline. In another example, the pressurized chamber captures instrument gas bled/leaked from the instruments and reinjects the instrument gas into the downstream portion of the pipeline.
Claims18
A fluid control system, comprising:
- a valve;
- a valve actuator, one or more instruments in fluidic communication with the valve actuator to actuate the valve;
- and
- a pressurized chamber, the one or more instruments being positioned within the pressurized chamber so that instrumentation gas passes through the instruments into the pressurized chamber prior to venting to a downstream portion of the pipeline;
- and
- wherein the pressurized chamber has a dynamically variable pressure corresponding to a pressure in a downstream portion of a pipeline.
A fluid control system, comprising:
- a valve;
- one or more instruments in fluidic communication with the valve;
- and
- a pressurized chamber fluidically connected to a downstream portion of a pipeline, the pressurized chamber having a dynamically variable pressure corresponding to a pressure in a downstream portion of a pipeline;
- wherein the one or more instruments are positioned within the pressurized chamber, surrounded by the dynamically variable pressure, so that the dynamically variable pressures sets a reference pressure for the one or more instruments within the pressurized chamber that is greater than or equal to the pressure in the downstream portion of the pipeline;
- and
- wherein instrumentation gas released by the one or more instruments is captured within the chamber and reinjected into the downstream portion of the pipeline.
A fluid control system, comprising:
- a pressurized chamber fluidically connected to a pipeline via a vent, so that the pressurized chamber has a dynamically variable pressure corresponding to a pressure in the pipeline;
- and
- one or more pneumatic instruments held within the chamber, so that the dynamically variable pressure provides a reference pressure for one or more instruments within the pressurized chamber that is greater than or equal to the pressure in the pipeline;
- wherein instrumentation gas passes through the one or more pneumatic instruments before being released by the one or more instruments and captured within the chamber;
- and
- wherein instrumentation gas captured within the chamber is reinjected into the pipeline via the vent.
Dependencies are inferred from the claim text.