Gas saving back pressure device
AssigneeTexaco Inc.
InventorJesse C. Scott
Life of this patent
Estimating the term…
Abstract
A back pressure control device is connected to the actuator of a control valve to limit the amount of gas released from the actuator after each actuation. Approximately two thirds of the volume of the actuation gas is retained in the actuator by the subject device after each actuation, this being both the release of a sufficient volume to assure actuation of the control valve while retaining gas which was heretofore wasted.
Claims10
In combination with a control valve connected to a vessel and responsive to control means sensing at least one condition in said vessel, said control valve having gas operated actuator responding to said control means to actuate said control valve, a back pressure control device connected to control the amount of gas released from said actuator after each actuation of said control valve, said back pressure device comprising:
- relay means connected between said control means, said actuator and exhaust, said relay means in a first position connecting said actuator to said control means and in a second position connecting said actuator to exhaust;
- coupling means connected to said exhaust of said relay means;
- and
- pressure responsive valve means connected to said coupling means and responsive to pressure of gas from the exhaust of said relay, said pressure responsive valve means having adjustable means to control the pressure at which said valve means will no longer allow release of gas from said actuator, whereby the gas in said actuator is never fully exhausted but only sufficient gas is released from the actuator to allow the control valve to be actuated.
A back pressure control device comprising:
- quick acting valve means connecting an actuator of a control valve to either a source of pressurized gas or to exhaust;
- coupling means connected to said quick acting valve means and to pressure gauge;
- and
- pressure responsive valve means connected between said coupling means and exhaust and adjustable to close communication with exhaust upon pressure dropping to a predetermined level.
A method for controlling the back pressure in an actuator of a control valve so as to retain sufficient gas within the actuator to allow the control valve to actuate without wasting gas through unnecessary venting, said method comprising the steps of:
- providing a control valve actuator with back pressure control means having quick acting valve means connected between said actuator and control means, a coupling connected to an exhaust port of said valve means, a pressure gauge connected to said coupling, and pressure responsive valve means connected between said coupling means and exhaust;
- setting said pressure responsive valve means to a pressure low enough to allow the control valve to actuate;
- and
- venting only enough gas from said actuator to allow the control valve to operate.
Dependencies are inferred from the claim text.