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 responsive to at least a threshold amount of temperature change of the shape memory alloy element. The valve actuator further includes a negative-differential spring applied to the shape memory alloy element, thereby reducing the threshold amount of temperature change needed to cause movement of the valve between the first and second positions.

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.

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 at a predetermined temperature and responsive to at least a threshold amount of temperature change of the shape memory alloy element. The valve actuator further includes an expansion element attached to the shape memory alloy element, the expansion element responsive to temperature changes at a rate lower than a rate of change of temperature indicative of a valve leak, the expansion element adjusting tension on the shape memory alloy element, thereby changing the predetermined temperature.

Abstract: In one embodiment, a valve comprising a valve body; 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 pivotable between a closed position and an open position; an extending member connected to, and moveable in pivotable synchronization with, the fluid flow restraining member; and a shape memory alloy element attached to the extending member and the valve body, the shape memory alloy element causing a pivotal movement of the extending member between positions corresponding to the open and closed positions responsive to a change in temperature of the shape memory alloy element.

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.

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 at a predetermined temperature and responsive to at least a threshold amount of temperature change of the shape memory alloy element. The valve actuator further includes an expansion element attached to the shape memory alloy element, the expansion element responsive to temperature changes at a rate lower than a rate of change of temperature indicative of a valve leak, the expansion element adjusting tension on the shape memory alloy element, thereby changing the predetermined temperature.

Abstract: In one embodiment, a valve comprising a valve body; 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 pivotable between a closed position and an open position; an extending member connected to, and moveable in pivotable synchronization with, the fluid flow restraining member; and a shape memory alloy element attached to the extending member and the valve body, the shape memory alloy element causing a pivotal movement of the extending member between positions corresponding to the open and closed positions responsive to a change in temperature of the shape memory alloy element.