# US 2014/0150869 A1 · Gas-lift safety valve actuated by a sensor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0150869 A1 - Document ID: US20140150869A1 - Status: Published application - Kind: A1 - Application number: 13/691,340 - Filed: 2012-11-30 - Published: 2014-06-05 - Earliest claimed: 2012-11-30 - Assignees: Massachusetts Institute of Technology; Chevron U.S.A. Inc. - Applicants: Chevron U.S.A. Inc.; Massachusetts Institute of Technolog - Inventors: Changkuan Yu; Eric Wright Gilbertson; Franz Hover; Dennis Harris; Jose Arellano - Web page: https://patentgrep.com/patent/US20140150869A1 ## CPC - E21B 43/123: {Gas lift valves} - E21B 44/005: {Below-ground automatic control systems} - F16K 17/386: {the closure members being rotatable or pivoting} - F16K 31/002: {actuated by temperature variation (thermo-electric F16K31/025)} - F16K 31/025: {actuated by thermo-electric means} - Y10T 137/0318: Processes - Y10T 137/7737: Thermal responsive - Y10T 137/7761: Electrically actuated valve - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS - F16K: VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING {(devices for emptying and evacuating the excess liquid in valves or conduits F16L55/07)} - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A valve actuator, valve, and method of actuation of a valve are disclosed. The valve actuator includes a shape memory alloy element attachable to a valve body, capable of use with a valve to cause movement of the valve between first and second positions. The valve actuator also includes a sensor located within a well and capable of detecting the presence of a fluid based on a fluid property of the fluid. The valve actuator includes a power supply electrically connected to the sensor and the shape memory alloy element, capable of applying an electric current to the shape memory alloy element in response to the sensor detecting the presence of the fluid. The electric current causes a temperature of the shape memory alloy element to increase beyond a threshold temperature at which the shape memory alloy element actuates. ## Claims ### Claim 1 A valve actuator comprising: a shape memory alloy element attachable to a valve body, capable of use with a valve to cause movement of the valve between first and second positions responsive to at least a threshold amount of temperature change of the shape memory alloy element; a sensor located within a well, the sensor capable of detecting the presence of a fluid based on a fluid property of the fluid; and a power supply electrically connected to the sensor and the shape memory alloy element, the power supply capable of applying an electric current to the shape memory alloy element in response to the sensor detecting the presence of the fluid, the electric current causing a temperature of the shape memory alloy element to increase beyond a threshold temperature at which the shape memory alloy element actuates, thereby causing movement of the valve between the first and second positions. ### Claim 2 (depends on 1) The valve actuator of claim 1, wherein the shape memory alloy element contracts from a first length to a second length when heated from a first temperature to a second temperature by the electric current, wherein the first temperature is below the threshold temperature and the second temperature is above the threshold temperature. ### Claim 3 (depends on 2) The valve actuator of claim 2, wherein the first temperature is below an Austenitic start temperature, and wherein the second temperature is above an Austenitic finish temperature. ### Claim 4 (depends on 2) The valve actuator of claim 2, wherein the shape memory alloy element extends from the second length to the first length when cooled from a third temperature to a fourth temperature. ### Claim 5 (depends on 4) The valve actuator of claim 4, wherein the third temperature is a Martensitic start temperature and the fourth temperature is a Martensitic finish temperature. ### Claim 6 (depends on 1) The valve actuator of claim 1, wherein the first and second positions correspond to open and closed valve positions. ### Claim 7 (depends on 1) The valve actuator of claim 1, further comprising a circuit electrically connected between the sensor and the power supply, the circuit configured to electrically connect the power supply across the shape memory alloy element based on detection of the fluid by the sensor. ### Claim 8 (depends on 7) The valve actuator of claim 7, wherein the circuit includes a supercapacitor electrically connected in parallel with the shape memory alloy element. ### Claim 9 (depends on 1) The valve actuator of claim 1, wherein the sensor comprises a conductivity sensor including one or more electrodes. ### Claim 10 (depends on 1) The valve actuator of claim 1, wherein the sensor is selected from a group of sensors consisting of: a flowrate sensor; a flow direction sensor; a conductivity sensor; a pressure sensor; and a temperature sensor. ### Claim 11 (depends on 1) The valve actuator of claim 1, wherein the shape memory alloy element is selected to have a threshold temperature above an expected environmental temperature range of the valve actuator. ### Claim 12 (depends on 1) The valve actuator of claim 1, wherein the sensor is located within a valve orifice of the valve body associated with the valve actuator. ### Claim 13 A valve, comprising: a valve body located within a well; an orifice disposed within the valve body; a fluid flow restraining member located at a first location of the orifice, the fluid flow restraining member movable between a closed position and an open position; a shape memory alloy element connected to the fluid flow restraining member, the shape memory alloy element causing movement of the fluid flow restraining member between open and closed positions responsive to at least a threshold amount of temperature change of the shape memory alloy element; a sensor located within the orifice, the sensor capable of detecting the presence of a fluid based on a fluid property of the fluid; and a power supply electrically connected to the sensor and the shape memory alloy element, the power supply capable of applying an electric current to the shape memory alloy element in response to the sensor detecting the presence of the fluid, the electric current causing a temperature of the shape memory alloy element to increase beyond a threshold temperature at which the shape memory alloy element actuates, thereby causing movement of the valve between first and second positions. ### Claim 14 (depends on 13) The valve of claim 13, wherein the fluid flow restraining member is pivotable between the closed position and the open position. ### Claim 15 (depends on 13) The valve of claim 13, wherein the sensor is a flowrate sensor, a flow direction sensor, a conductivity sensor, a pressure sensor, or a temperature sensor. ### Claim 16 (depends on 13) The valve of claim 13, wherein the sensor is selected from a group of sensors consisting of: a flowrate sensor; a flow direction sensor; a conductivity sensor; a pressure sensor; and a temperature sensor. ### Claim 17 (depends on 13) The valve of claim 13, further comprising a circuit electrically connected between the sensor and the power supply, the circuit configured to electrically connect the power supply across the shape memory alloy element based on detection of the fluid by the sensor. ### Claim 18 (depends on 17) The valve of claim 17, wherein the circuit includes a supercapacitor electrically connected in parallel with the shape memory alloy element. ### Claim 19 A method of actuating a valve, the method comprising: detecting, via a sensor, the presence of a fluid in a valve orifice of a valve, wherein the fluid is detected by measuring a fluid property of the fluid; passing an electric current through a shape memory alloy element in response to detecting the presence of the fluid, the shape memory alloy element connected to a fluid flow restraining member of the valve, thereby increasing a temperature of the shape memory alloy element from a first temperature below a threshold temperature to a second temperature above the threshold temperature, thereby actuating movement of the fluid flow restraining member between an open position and a closed position. ### Claim 20 (depends on 19) The method of claim 19, wherein detecting the presence of the fluid in the valve orifice of the valve includes detecting, based on conductivity, the presence of oil within the valve orifice based on conductivity of the fluid in the valve orifice, thereby detecting a backflow condition. ### Claim 21 (depends on 19) The method of claim 19, wherein detecting the presence of the fluid in the valve orifice of the valve occurs in response to periodically transmitting a current to an electrode within the valve orifice to detect conductivity of the fluid.