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: 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: 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: Methods and apparatus for enhanced and improved viscous oil recovery are disclosed. A horizontal well is drilled through the viscous oil formation. A liner includes temperature actuated valves for delivering steam more uniformly along the heel and toe portions of the liner. The temperature actuated valves include an actuation mechanism that actuates from an open position to a closed position to control the flow of the steam therethrough. The actuation mechanism actuates to the closed position when it exceeds a predetermined temperature. Heat from the steam mobilizes and lowers the viscosity of the heavy crude wherein the crude is then produced to the surface via conventional lift arrangements.