JP2018028374A - Motor-operated valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor-operated valve capable of remotely performing a valve closing operation or a valve opening operation in the case where an accident of all power supply loss has occurred in a power generation plant.SOLUTION: A motor-operated valve 1 includes: a valve device 10 for opening/closing a control flow passage 2 of a power generation plant; an electric motor 21 for electrically opening/closing the valve device; and a manual handle 23 for manually opening/closing the valve device. The motor-operated valve 1 also includes: a pneumatic motor 31 for rotationally driving the manual handle; an air cylinder 32 for supplying compressed air to the pneumatic motor; and a solenoid valve 34 provided at an air pipe 33 for connecting the pneumatic motor and the air cylinder, and constituted so as to hold a valve closing state while power is supplied to the electric motor from an external power supply and to open the valve in the case where the power supply from the external power supply is stopped.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electric valve provided in a control flow path of a power plant.

  Various plants including nuclear power plants are equipped with piping for flowing gases such as air, nitrogen or steam, and liquids such as water. The flow in the piping is interrupted and opened in the middle of this piping. Thus, a motor-operated valve that adjusts the flow rate, pressure, and the like is provided.

  The electric valve shuts off or opens the pipe by operating the valve body with the driving force of the electric motor. Therefore, when the power supply from the external power source to the motor-operated valve is stopped, the flow rate, pressure, etc. of the pipe provided with the motor-operated valve cannot be adjusted. Therefore, ensuring the reliability of the power supply is important in the power plant. Here, for example, Patent Literature 1 discloses a technique for improving the reliability of the power source of a nuclear power plant.

  Patent Document 1 states that “a reactor pressure vessel 2 stored in a reactor containment vessel 1, a main steam pipe 25 and a water supply pipe 26 connected to the reactor pressure vessel 2, and a plurality of sections are separated and independent. A plurality of water injection systems for injecting water into the reactor pressure vessel 2, a plurality of power supply facilities for supplying power to the equipment in the water injection system separately for each section, and a main steam pipe 25 through a pipe 9. The steam received in the condenser 6 is condensed in the condenser 6, and the isolation condenser system for returning the condensed water to the water supply pipe 26 through the pipe 63, and the motor operated valves 7 a, 7 b, 7 c, provided in the pipes 9, 63, It is a safety facility for a nuclear reactor in which the power supply to 8a, 8b, 8c is the plurality of power supply facilities "(see summary).

JP 2004-219342 A

  According to the reactor safety facility described in Patent Document 1, by providing a plurality of power source facilities, the motor-operated valve can be opened and closed if at least one of the power source facilities is functioning.

  However, when an all-power-loss accident occurs and all of the plurality of power supply facilities stop functioning, it is still impossible to open and close the motor-operated valve. Note that a motor-driven valve used in a power plant is generally provided with a manual handle so that it can be opened and closed even when power supply from an external power source is stopped (for example, during periodic inspection). Therefore, even when the external power source is lost, the motor-operated valve can be manually opened and closed. However, depending on the situation of the accident, there may be a situation in which the worker cannot enter the motorized valve installation area.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a motor-operated valve that can be remotely closed or opened even when a total power loss accident occurs in a power plant. There is to do.

  In order to solve the above problems, the present invention provides an electric motor comprising a valve device that opens and closes a control flow path of a power plant, an electric motor that electrically opens and closes the valve device, and a manual handle that manually opens and closes the valve device. In the valve, provided in a pneumatic motor that rotationally drives the manual handle, an air cylinder that supplies compressed air to the pneumatic motor, and an air pipe that connects the pneumatic motor and the air cylinder, and an external power supply to the electric motor A solenoid valve configured to maintain a closed state while power is supplied from the power source and to be opened when power supply from the external power supply is stopped.

  According to the present invention, when a total power loss accident occurs in a power plant, an electromagnetic valve provided in an air pipe connecting the pneumatic motor and the air cylinder is opened, and compressed air is supplied from the air cylinder to the pneumatic motor. By supplying and rotating the manual handle in the valve closing operation direction or the valve opening operation direction, the electric valve can be closed or opened.

It is a figure which shows the structure of the motor operated valve which concerns on 1st Example of this invention. It is a flowchart which shows the operation | movement at the time of the power supply stop of the motor operated valve which concerns on 1st Example of this invention. It is a figure which shows the structure of the motor operated valve which concerns on 2nd Example of this invention. It is a flowchart which shows the operation | movement at the time of the power supply stop of the motor operated valve which concerns on 2nd Example of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, in each figure, the same code | symbol is attached | subjected to the same member and the overlapping description is abbreviate | omitted suitably.

  FIG. 1 is a diagram showing a configuration of a motor-operated valve according to a first embodiment of the present invention.

  In FIG. 1, a motor-operated valve 1 according to this embodiment is provided in a control flow path 2 of a power plant, and adjusts the flow rate, pressure, and the like of the control flow path 2.

  The electric valve 1 includes a valve device 10 that shuts off or opens the control flow path 2 and a valve drive device 20 that drives the valve device 10.

  The valve device 10 includes a valve box 11 interposed in the control flow path 2, a position (hereinafter referred to as “closed position”) for closing the control flow path 2 in the valve box 11, and a position (hereinafter referred to as “open position”). And a valve rod 13 that is connected to the valve body 12 and operates the valve body 12 between an open position and a closed position.

  The valve drive device 20 includes an electric motor 21 as a power source, and a transmission mechanism 22 that converts a rotational driving force (torque) of the electric motor 21 into a linear driving force of the valve rod 13. When the electric motor 21 is rotated in one direction, the valve body 12 is operated from the stop position to the open position via the valve rod 13, and the control flow path 2 is opened. On the other hand, when the electric motor 21 is rotated in the other direction, the valve body 12 is operated from the open position to the illustrated closed position via the valve rod 13, and the control flow path 2 is shut off.

  In addition, the valve drive device 20 is provided with a manual handle 23 that can be manually rotated, and the rotational force of the manual handle 23 is converted into a linear drive force of the valve stem 13 via the transmission mechanism 22. When the operator rotates the manual handle 23 in one direction, the valve body 12 is operated from the stop position to the open position via the valve rod 13, and the control flow path 2 is opened. On the other hand, when the manual handle 23 is rotated in the other direction, the valve body 12 is operated from the open position to the illustrated closed position via the valve rod 13, and the control flow path 2 is shut off. Thereby, even when the power supply from the external power supply is stopped, such as during periodic inspection of the power plant, the control flow path 2 can be manually cut off or opened.

  The motor-operated valve 1 according to the present embodiment further includes a pneumatic drive device 30 for rotationally driving the manual handle 23.

  The pneumatic drive device 30 is provided in a pneumatic motor 31 attached to the manual handle 23, an air cylinder 32 that supplies compressed air to the pneumatic motor 31, and an air pipe 33 that connects the pneumatic motor 31 and the air cylinder 32. The electromagnetic valve 34 is provided. In addition, arrangement | positioning of the air cylinder 32, the air piping 33, and the solenoid valve 34 is not limited to the example shown in FIG.

  The pneumatic motor 31 is driven by compressed air supplied from an air cylinder 32 and operates the manual handle 23 in a direction (hereinafter referred to as “valve closing operation direction”) in which the valve body 12 is operated to the closed position or in an open position. It is rotated in the direction (hereinafter referred to as “the valve opening operation direction”). Here, it is desirable that the pneumatic motor 31 is configured to be detachable from the manual handle 23. As a result, the pneumatic drive device 30 can be easily attached to the manual handle 23 of the existing motor-operated valve 1.

  The electromagnetic valve 34 is a normally open valve that closes in an excited state and opens in a non-excited state, and is directly excited by an external power source. Thus, the pneumatic motor 31 is not driven while power is supplied from the external power source, and the valve body 12 can be opened and closed by the driving force of the electric motor 21 as in the conventional electric valve. it can.

  FIG. 2 is a flowchart showing the operation of the motor-operated valve 1 according to this embodiment when the power supply is stopped. Hereinafter, each step will be described in order.

  In FIG. 2, first, when the power supply from the external power supply is stopped (step S10), the electric motor 21 becomes inoperable and the excitation of the electromagnetic valve 34 is released (step S20).

  When the excitation of the solenoid valve 34 is released, the solenoid valve 34 is opened (step S30).

  When the electromagnetic valve 34 is opened, the air pipe 33 is opened, and compressed air is supplied from the air cylinder 32 to the pneumatic motor 31 (step S40).

  When compressed air is supplied to the pneumatic motor 31, the pneumatic motor 31 rotates and the manual handle 23 is rotationally driven in the valve closing operation direction (or valve opening operation direction) (step S50).

  When the manual handle 23 is rotationally driven in the valve closing operation direction (or valve opening operation direction), the valve body 12 is operated to the closed position (or open position) (step S60), and the control flow path 2 is shut off (or Is released (step S70).

  According to the electric valve 1 according to the present embodiment, when the power supply from the external power supply is stopped, the electromagnetic valve 34 is automatically opened to supply the compressed air from the air cylinder 32 to the pneumatic motor 31, The manual handle 23 can be rotationally driven in the valve closing operation direction (or the valve opening operation direction). As a result, even when a power loss accident occurs in the power plant and the operator cannot enter the installation area of the motor-operated valve 1, the control flow path 2 can be shut off (or opened).

  FIG. 3 is a diagram showing the configuration of the motor-operated valve according to the second embodiment of the present invention.

  The motor-operated valve 1A according to the present embodiment will be described focusing on the differences from the first embodiment.

  In the first embodiment (shown in FIGS. 1 and 2), since the electromagnetic valve 34 is directly excited by an external power supply, the electromagnetic valve 34 opens simultaneously with the stop of power supply from the external power supply. Therefore, when a total power loss accident occurs in the power plant, the control flow path 2 can be shut off (or opened) immediately after the accident occurs.

  However, depending on the situation of the accident (for example, when only the external power source that supplies power to the motor-operated valve 1 is stopped and other power sources are functioning), the control flow path 2 is shut off immediately after the accident occurs (or It is also assumed that some inconvenience will occur by opening.

  The motor-operated valve 1A according to the present embodiment controls the control flow path 2 at the timing when the operator 51 in the remote area 50 separated from the installation area of the motor-operated valve 1A determines that the power supply from the external power source is stopped. Can be blocked (or opened).

  In FIG. 3, the electric valve 1 </ b> A further includes a power storage device 35, and is configured to excite the electromagnetic valve 34 with the power storage device 35 instead of directly exciting the electromagnetic valve 34 with an external power source. Here, it is desirable that the power storage device 35 is configured to be constantly charged by an external power source. This eliminates the need for charging the power storage device 35. The arrangement of the power storage device 35 is not limited to the example shown in FIG.

  Further, the power storage device 35 is configured to hold the electromagnetic valve 34 in a closed state until a valve opening command described later is received. That is, when the solenoid valve 34 is a normally open valve that opens in a non-excited state, the solenoid valve 34 is held in an excited state, and when the solenoid valve 34 is a normally closed valve that closes in a non-excited state, the solenoid valve 34 34 is held in a non-excitation excitation. Thus, the pneumatic motor 31 is not driven until a valve opening command to be described later is received, and the valve body 12 can be opened and closed by the driving force of the electric motor 21 as in the case of the conventional electric valve. .

  In the remote area 50, an operation panel 52 operated by an operator 51 is arranged. The operation panel 52 receives an operation of the operator 51 and transmits a valve opening command to the power storage device 35. When receiving the valve opening command from the operation panel 52, the power storage device 35 releases the excitation when the solenoid valve 34 is normally open, and starts the excitation when the solenoid valve 34 is normally open. 34 is opened.

  FIG. 4 is a flowchart showing the operation of the motor operated valve 1A according to this embodiment when the power supply is stopped. Hereinafter, each step will be described in order.

  In FIG. 4, first, when the power supply from the external power supply is stopped (step S10), the electric motor 21 becomes inoperable. At this time, the excitation state (or non-excitation state) of the electromagnetic valve 34 is held by the power storage device 35 (step S21).

  Thereafter, a valve opening command is transmitted to the power storage device 35 through the operation panel 52 that has been operated by the operator 51 (step S22).

  Subsequently, the excitation of the electromagnetic valve 34 is released (or started) by the power storage device 35 that has received the valve opening command from the operation panel 52 (step S23).

  When the excitation of the solenoid valve 34 is released (or started), the solenoid valve 34 is opened (step S31).

  Subsequent steps S40 to S70 are the same as those in the first embodiment (shown in FIG. 2), and thus the description thereof is omitted.

  According to the motor operated valve 1A according to the present embodiment, when the power supply from the external power supply is stopped, the electromagnetic valve 34 is remotely opened to supply compressed air from the air cylinder 32 to the pneumatic motor 31. The manual handle 23 can be rotationally driven in the valve closing operation direction (or the valve opening operation direction). As a result, even when an all-power loss accident occurs in the power plant and an operator cannot enter the installation area of the motor-operated valve 1, the control flow path is determined at the timing when the operator 51 in the remote area 50 determines that it is appropriate. 2 can be blocked (or opened).

  As mentioned above, although the Example of this invention was explained in full detail, this invention is not limited to an above-described Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. It is also possible to add a part of the configuration of another embodiment to the configuration of a certain embodiment, and delete a part of the configuration of a certain embodiment or replace it with a part of another embodiment. Is possible.

  DESCRIPTION OF SYMBOLS 1,1A ... Electric valve, 2 ... Control flow path, 10 ... Valve apparatus, 11 ... Valve box, 12 ... Valve body, 13 ... Valve rod, 20 ... Valve drive device, 21 ... Electric motor, 22 ... Transmission mechanism, 23 DESCRIPTION OF SYMBOLS ... Manual handle, 30 ... Pneumatic drive device, 31 ... Pneumatic motor, 32 ... Air cylinder, 33 ... Air piping, 34 ... Solenoid valve, 35 ... Power storage device, 50 ... Remote area, 51 ... Operator, 52 ... Control panel.

Claims (6)

A valve device for opening and closing the control flow path of the power plant;
An electric motor for electrically opening and closing the valve device;
In an electric valve provided with a manual handle for manually opening and closing the valve device,
A pneumatic motor for rotationally driving the manual handle;
An air cylinder for supplying compressed air to the pneumatic motor;
Provided in an air pipe connecting the pneumatic motor and the air cylinder, and when the electric motor is supplied with electric power from an external power source, the valve is kept closed and the electric power supply from the external power source is stopped. And a solenoid valve configured to be openable. The motor-operated valve according to claim 1,
The motor-operated valve, wherein the pneumatic motor is configured to be detachable from the manual handle. The motor-operated valve according to claim 1,
The motor-operated valve, wherein the solenoid valve is configured to maintain a closed state by being directly excited by the external power source. The motor-operated valve according to claim 1,
A power storage device,
The electromagnetic valve is configured as a normally open valve that is kept closed by being excited by the power storage device,
The electric storage device is configured such that the electromagnetic valve can be de-energized by remote control. The motor-operated valve according to claim 1,
A power storage device,
The electromagnetic valve is configured as a normally closed valve that maintains a closed state by being not excited by the power storage device,
The electric storage device, wherein the power storage device is configured to start excitation of the electromagnetic valve by remote control. In the motor operated valve according to claim 4 or 5,
The electric storage device is configured to be constantly charged by the external power source.

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