Multi-motion fail-safe operating gate valve
A valve assembly includes a valve body and a valve member configured to translate between an open and a closed position. The valve assembly also includes a bonnet coupled to the valve body and a valve stem coupled to the valve member. The valve assembly also includes an actuator coupled to the bonnet. The actuator includes a first drive mechanism positioned to translate a first driving force to the valve stem, the first drive mechanism being in operation during a normal operating condition. The actuator also includes a second drive mechanism positioned to translate a second driving force to the valve stem, the second drive mechanism being in operation during a fail-safe operating condition.
1. A valve assembly, comprising:
a valve body;
a valve member configured to translate between an open and a closed position within the valve body;
a bonnet coupled to the valve body;
a valve stem coupled to the valve member and extending through a bore of the bonnet; and
an actuator coupled to the bonnet, the actuator comprising:
a first drive mechanism positioned to translate a first driving force to the valve stem, the first drive mechanism being in operation during a normal operating condition; and
a second drive mechanism positioned to translate a second driving force to the valve stem, the second drive mechanism being in operation during a fail-safe operating condition; wherein the first drive mechanism does not apply the first driving force during operation of the second drive mechanism; the first driving force is a rotational force and the second driving force is an axial force; a retention member releasably coupled to the second drive mechanism, wherein the retention member blocks operation of the second drive mechanism when engaged and enables operation of the second drive mechanism when released; and the retention member is at least one of a solenoid valve, a hydraulic force, a pneumatic force, or a vacuum force.
2. The valve assembly of claim 1 , further comprising:
a valve stroke system, the valve stroke system being coupled to the valve stem and being moveable along an axis of the valve stem along with the valve member, wherein the valve stroke system restricts axial travel of the valve stem.
3. The valve assembly of claim 1 , wherein the second drive mechanism comprises a spring coupled to a plate, further comprising:
a compression mechanism coupled to the second drive mechanism, wherein the compression mechanism comprises a rod coupled to the plate at a first end and to a ball screw at the second end, wherein rotation of the ball screw drives axial movement of the rod to compress the spring.
4. An actuator for use with a valve, comprising:
a first drive mechanism for applying a first driving force to a valve stem, the first drive mechanism arranged within an actuator housing and configured to couple to the valve stem at an interface;
a second drive mechanism for applying a second driving force to the valve stem, the second drive mechanism arranged, at least partially, within the actuator housing and configured to couple to the valve stem at a second interface; and
a retention member associated with the second drive mechanism, the retention mechanism releasably maintaining the second drive mechanism at a first position, where the second driving force acts on the retention member, and enabling movement to a second position, where the second driving force acts on the valve stem; at least one of the first drive mechanism and the second drive mechanism is an electric motor; the interface comprises splines of the electric motor interacting with splines of the valve stem; and the retention member comprises: a piston; a cylinder, the cylinder receiving the piston and having an inlet axially lower than a piston head; and a valve associated with the cylinder, the valve blocking a working fluid at least one of entering or exiting the cylinder.
5. The actuator of claim 4 , further comprising:
a valve stroke system, the valve stroke system being coupled to the valve stem and being moveable along an axis of the valve stem, wherein the valve stroke system restricts axial travel of the valve stem.
6. The actuator of claim 4 , wherein the first driving force is a rotational force and the second driving force is an axial force.
7. The actuator of claim 4 , wherein the first drive mechanism does not apply the first driving force when the second drive mechanism applies the second driving force.
8. The actuator of claim 4 , wherein the retention member is at least one of a solenoid valve, a hydraulic force, a pneumatic force, or a vacuum force.
9. The actuator of claim 4 , wherein the second driving mechanism comprises:
a biasing member; and
a plate coupled to the biasing member and to the valve stem, the plate being driven axially by the biasing member.
10. The actuator of claim 4 , wherein the valve is activated by a signal indicative of a fail-safe operation mode.