A hydraulic control device for an emergency stop valve of a steam turbine has a module for reducing a hydraulic pressure by rapid opening of an outflow valve and/or unloading or loading an actuator for actuating the emergency stop valve. In an operating medium supply and/or conducting system a control valve arrangement with at least three safety valves is provided, which are hydraulically interconnected such that they open the outflow valve or unload or load the actuator only when a safety circuit by way of at least two safety valves of the control valve arrangement has assumed an emergency stop position. A precontrol valve that is independent from the remaining safety valves is hydraulically connected upstream of each safety valve. A safety valve that is connected downstream of a respective precontrol valve can be hydraulically decoupled from the same during the operation.

A steam turbine valve abnormality monitoring system according to an embodiment includes a detection unit detecting the state of a steam turbine valve or a steam turbine valve drive device, a determination unit, and an abnormality processing unit. Based on the detected result of the detection unit, the determination unit determines whether or not an abnormality has occurred in the opening degree control of the steam turbine valve. The abnormality processing unit issues an alarm or issues a turbine stop command when the determination unit determines that an abnormality has occurred in the opening degree control of the steam turbine valve.

A steam turbine valve abnormality monitoring system according to an embodiment includes a detection unit detecting the state of a steam turbine valve or a steam turbine valve drive device, a determination unit, and an abnormality processing unit. Based on the detected result of the detection unit, the determination unit determines whether or not an abnormality has occurred in the opening degree control of the steam turbine valve. The abnormality processing unit issues an alarm or issues a turbine stop command when the determination unit determines that an abnormality has occurred in the opening degree control of the steam turbine valve.

A dual trip manifold assembly (TMA) includes an isolation valve assembly having a first valve configured to receive a flow of fluid from a hydraulic system fluid supply. The first valve is configured to channel the flow of fluid to at least one hydraulic circuit. The isolation valve assembly also includes a second valve configured to receive the flow of fluid from the at least one hydraulic circuit of the at least two hydraulic circuits. The second valve is further configured to channel the fluid flow to a trip header and to receive the fluid flow from the trip header. The first valve and the second valve are synchronized to each other such that rotation of one of said first and second valves causes a substantially similar rotation in the other of said first and second valves header.

A dual trip manifold assembly (TMA) includes an isolation valve assembly having a first valve configured to receive a flow of fluid from a hydraulic system fluid supply. The first valve is configured to channel the flow of fluid to at least one hydraulic circuit. The isolation valve assembly also includes a second valve configured to receive the flow of fluid from the at least one hydraulic circuit of the at least two hydraulic circuits. The second valve is further configured to channel the fluid flow to a trip header and to receive the fluid flow from the trip header. The first valve and the second valve are synchronized to each other such that rotation of one of said first and second valves causes a substantially similar rotation in the other of said first and second valves header.

The emergency shutoff device is provided with a casing (21) in which inflow ports (22) through which control oil flows into a space (A1) provided therein and a plurality of outflow ports (23) through which the control oil flows outside of the space (A1) are formed; and a switching unit (24) configured to slide along an inner circumferential surface of the casing (21) in which the space (A1) is formed, to change its position relative to the plurality of outflow ports (23), and thus to switch a circulation state of the control oil in the space (A1). The switching unit (24) switches the circulation state between the first circulation state in which the control oil is circulated from a first inflow port (221) to a first outflow port (231) and the third circulation state in which an open and closed state of a test outflow port (236) is switched while the control oil is being circulated from the first inflow port (221) to the first outflow port (231).

The emergency shutoff device is provided with a casing (21) in which inflow ports (22) through which control oil flows into a space (A1) provided therein and a plurality of outflow ports (23) through which the control oil flows outside of the space (A1) are formed; and a switching unit (24) configured to slide along an inner circumferential surface of the casing (21) in which the space (A1) is formed, to change its position relative to the plurality of outflow ports (23), and thus to switch a circulation state of the control oil in the space (A1). The switching unit (24) switches the circulation state between the first circulation state in which the control oil is circulated from a first inflow port (221) to a first outflow port (231) and the third circulation state in which an open and closed state of a test outflow port (236) is switched while the control oil is being circulated from the first inflow port (221) to the first outflow port (231).

A hydraulic lock apparatus includes a hydraulic actuator, a pressure storage device connected to the hydraulic actuator, and a control valve configured to actuate to a first position and a second position. The control valve fluidly isolates the pressure storage device from the hydraulic actuator when the control valve is in the first position. The control valve fluidly connects the pressure storage device to the hydraulic actuator when the control valve is in the second position.

A hydraulic lock apparatus includes a hydraulic actuator, a pressure storage device connected to the hydraulic actuator, and a control valve configured to actuate to a first position and a second position. The control valve fluidly isolates the pressure storage device from the hydraulic actuator when the control valve is in the first position. The control valve fluidly connects the pressure storage device to the hydraulic actuator when the control valve is in the second position.

A dual trip manifold assembly (TMA) includes an isolation valve assembly having a first valve configured to receive a flow of fluid from a hydraulic system fluid supply. The first valve is configured to channel the flow of fluid to at least one hydraulic circuit. The isolation valve assembly also includes a second valve configured to receive the flow of fluid from the at least one hydraulic circuit of the at least two hydraulic circuits. The second valve is further configured to channel the fluid flow to a trip header and to receive the fluid flow from the trip header. The first valve and the second valve are synchronized to each other such that rotation of one of said first and second valves causes a substantially similar rotation in the other of said first and second valves header.