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Actuators having override apparatus are described herein. An example actuator having an override apparatus includes a first actuator stem coupled to a control actuation member. The override apparatus is operatively coupled to the actuator. A spring is coupled to an override member to move the first

Actuators having override apparatus are described herein. An example actuator having an override apparatus includes a first actuator stem coupled to a control actuation member. The override apparatus is operatively coupled to the actuator. A spring is coupled to an override member to move the first actuator stem to a predetermined position in response to an override condition.

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1. An actuator having an override apparatus, comprising: an actuator stem to couple a control actuator to a flow control member of a fluid valve;an override actuator to be selectively coupled to the control actuator via a connector in response to an override condition and selectively decoupled from

1. An actuator having an override apparatus, comprising: an actuator stem to couple a control actuator to a flow control member of a fluid valve;an override actuator to be selectively coupled to the control actuator via a connector in response to an override condition and selectively decoupled from the control actuator when the control actuator is in an operational state, the actuator stem having a first stem to be slidably coupled to one of the control actuator or the override actuator and a second stem to be coupled to the other one of the control actuator or the override actuator, the override actuator being positioned between the control actuator and a fluid valve, the connector being fixed to the actuator stem along a length of the actuator stem and positioned away from the control actuator and the override actuator to operatively decouple the control actuator and the override actuator when the control actuator is in the operational state; anda spring operatively coupled to the override actuator to cause the override actuator to move the actuator stem to a predetermined position via engagement with the connector in response to the override condition. 2. An actuator of claim 1, wherein the control actuator comprises a pneumatic piston or a spring and diaphragm actuator. 3. An actuator of claim 1, wherein the spring is in a compressed condition prior to the override condition, and wherein the spring extends to move the override actuator and the actuator stem to the predetermined position via engagement with the connector in response to the override condition. 4. An actuator of claim 1, wherein the override actuator does not affect the operation of the control actuator prior to the override condition. 5. An actuator of claim 1, wherein the first and second stems are coupled via the connector. 6. An actuator of claim 1, wherein the spring and the override actuator are configured to provide a fail-to-open fail-safe operation in response to the override condition. 7. An actuator of claim 1, wherein the spring and the override actuator are configured to provide a fail-to-close fail-safe operation in response to the override condition. 8. An actuator of claim 1, wherein the predetermined position is adjustable by varying an amount of force exerted on the override actuator. 9. An actuator of claim 1, wherein the override actuator has an opening to slidably receive the actuator stem to enable movement of the control actuator relative to the override actuator when the control actuator is in an operational state. 10. An actuator of claim 1, wherein the connector is to prevent the actuator stem from sliding relative to the opening of the override actuator when the control actuator is in the override condition. 11. An actuator of claim 1, wherein the connector does not directly engage the override and the control actuator when the control actuator is in the operational state. 12. An actuator of claim 1, wherein the connector, via the actuator stem, is to move between the override actuator and the control actuator when the control actuator is in the operational state. 13. An actuator having an override apparatus, comprising: a first actuator having a first actuation apparatus disposed in a first housing to define a first chamber and a second chamber, the first chamber to receive a control fluid to cause the first actuation apparatus to move in a first direction and the second chamber to receive the control fluid to cause the first actuation apparatus to move in a second direction opposite the first direction when the first actuator is in an operational state;a second actuator having a second actuation apparatus disposed in a second housing to define a third chamber and a fourth chamber, the second actuation apparatus including a piston or diaphragm to move within the second housing, the third chamber is to receive the control fluid to cause the second actuation apparatus to move to a stored position when the first actuator is in an operational state;a stem having a first portion coupled to the first actuation apparatus and a second portion that slidably extends through an opening formed in the piston or diaphragm of the second actuation apparatus; anda biasing element disposed in the fourth chamber to cause the second actuation apparatus to move the first actuation apparatus to a predetermined position when the control fluid is released from the third chamber and the first actuator is in a non-operational state, the second actuator to move the first actuation apparatus to the predetermined position via the biasing element without use of the control fluid. 14. An actuator of claim 13, wherein the first housing is mounted inside the second housing. 15. An actuator of claim 13, wherein the biasing element comprises a spring. 16. An actuator of claim 13, further comprising a canister coupled to the second actuation apparatus and slidably coupled to a spring seat, wherein the biasing element is disposed between the canister and the spring seat. 17. An actuator of claim 13, wherein the first actuation apparatus comprises a piston or diaphragm plate. 18. An actuator of claim 13, wherein the second actuator does not act upon the first actuator when the first actuator is in an operational state. 19. An actuator of claim 13, further comprising a connector fixed to an outer surface of the stem, the connector positioned away from the first and second actuation apparatus to operatively decouple the first and second actuation apparatus when the first actuator is in the operational state. 20. An actuator of claim 19, wherein the connector includes a flanged portion to engage the first actuation apparatus or the second actuation apparatus when the second actuation apparatus moves to the predetermined position. 21. An actuator of claim 19, wherein the connector rigidly couples the first portion of the stem and the second portion of the stem. 22. An actuator of claim 19, wherein the connector operatively couples the first actuation apparatus and the second actuation apparatus when the first actuator is in a non-operational state to enable the second actuation apparatus to move the first actuation apparatus to the predetermined position. 23. An actuator of claim 19, wherein the connector is to move within the third chamber when the first actuator is in the operational state. 24. An actuator having an override apparatus, comprising; means for moving a first actuator positioned in a first housing between a first position and a second position;means for connecting the first actuator to means for controlling fluid flow through a fluid valve;means for moving a second actuator positioned in a second housing to a stored position when the means for moving the first actuator is in an operational state, the means for connecting having a first portion slidably received in an opening formed in the first actuator or the second actuator to enable the first actuator or the second actuator to slide along the first portion of the means for connecting, the means for connecting having a second portion coupled to the other one of the first actuator or the second actuator;means for operatively coupling the first actuator and the second actuator in response to an override condition, the means for operatively coupling being fixed to the means for connecting and positioned away from the first and second actuator to operatively decouple the first and second actuator when the first actuator is in the operational state, and the means for operatively coupling to engage a portion of the first actuator or the second actuator in response to the override condition to enable the second actuator to move the first actuator to a predetermined position in response to the override condition; andmeans for adjusting the predetermined position by varying an amount of force exerted on the second means for actuating. 25. An actuator of claim 24, wherein the means for moving the first actuator comprises means for fluidly coupling a first side of the first actuator to a control fluid supply source and means for fluidly coupling a second side of the first actuator to the control fluid supply source. 26. An actuator of claim 25, wherein the means for moving the second actuator to the stored position comprises means for fluidly coupling a first side of the second actuator to the control fluid supply source. 27. An actuator of claim 24, wherein the override condition is a non-operational state. 28. An actuator of claim 24, wherein the first actuator comprises first means for actuating positioned in a first housing to define a first chamber and a second chamber and the second actuator comprises second means for actuating positioned in a second housing to define a third chamber and a fourth chamber, wherein the means for moving moves the first means for actuating between a first position and a second position via the first and second chambers and the second means for actuating to a stored position via the third chamber when the first means for actuating is in an operational state. 29. An actuator of claim 28, further comprising means for biasing disposed within the fourth chamber to cause the second means for actuating to move the first means for actuating to the predetermined position when the means for moving the second means for actuating to the stored position is released from the third chamber and the first means for actuating is in a non-operational state, the second means for actuating to move the first means for actuating to the predetermined position without use of the means for moving. 30. An actuator having an override apparatus, comprising: an actuator stem to couple a control actuator to a flow control member of a fluid valve;an override actuator to be selectively coupled to the control actuator via a connector during operation of the actuator, the actuator stem having a first stem to be slidably coupled to one of the control actuator or the override actuator and a second stem to be coupled to the other one of the control actuator or the override actuator the connector being fixed to the actuator stem along a length of the actuator stem and positioned away from the control actuator and the override actuator to operatively decouple the control actuator and the override actuator when the control actuator is in the operational state; anda spring operatively coupled to the override actuator to cause the override actuator to move the actuator stem to a predetermined position via engagement with the connector in response to an override condition, the connector, via the actuator stem, is to move between the override actuator and a spring seat supporting the spring when the control actuator is in an operational state. 31. An actuator of claim 30, wherein the spring is in a compressed condition prior to the override condition, and wherein the spring extends to move the override actuator and the actuator stem to the predetermined position via engagement with the connector in response to the override condition. 32. An actuator of claim 30, wherein the connector does not directly engage the override and the control actuator when the control actuator is in the operational state. 33. An actuator of claim 1, having an override apparatus, comprising: an actuator stem to couple a control actuator to a flow control member of a fluid valve;an override actuator selectively coupled to the control actuator via a connector, the actuator stem having a first stem to be slidably coupled to one of the control actuator or the override actuator and a second stem to be coupled to the other one of the control actuator or the override actuator, the override actuator being positioned between the control actuator and a fluid valve, wherein the override actuator comprises a piston, the actuator stem to extend between a first side of the piston and a second side of the piston via an opening through the piston, and wherein an end of the actuator stem is rigidly coupled to the control actuator; anda spring operatively coupled to the override actuator to cause the override actuator to move the actuator stem to a predetermined position via engagement with the connector in response to an override condition.