WO2017104035A1

WO2017104035A1 - Main stop valve, and steam turbine provided with same

Info

Publication number: WO2017104035A1
Application number: PCT/JP2015/085306
Authority: WO
Inventors: 賢西谷; 誠片懸; 真紀夫森本
Original assignee: 三菱重工コンプレッサ株式会社
Priority date: 2015-12-17
Filing date: 2015-12-17
Publication date: 2017-06-22
Also published as: JPWO2017104035A1

Abstract

Provided are: a main stop valve which is not hydraulically driven; and a steam turbine provided with said main stop valve. In this main stop valve for opening and closing a flow path through which steam flows, and this steam turbine provided with said main stop valve, provided are: a valve body (16) which opens and closes an opening of a valve seat (15) in the flow path, to open and close the flow path; a rod (21) which moves the valve body (16) linearly with respect to the valve seat (15); an electric actuator part (19) provided with a piston (31a) which moves linearly; and a connection state changing part (18) which changes the connection state between the rod (21) and the piston (31a) to a connected state or a unconnected state, sets the rod (21) and the piston (31a) in the connected state at times other than during emergencies, and sets the rod (21) and the piston (31a) in the unconnected state during emergencies.

Description

Main stop valve and steam turbine equipped with the same

The present invention relates to a main stop valve and a steam turbine provided with the same.

A main stop valve (Trip and Throttle Valve; hereinafter referred to as TTV) is provided on the inlet side of the steam turbine, and the mechanism for driving this TTV uses the hydraulic pressure of control oil.

Japanese Utility Model No. 2-9041 Japanese Utility Model No. 2-9042

FIG. 6 shows a schematic view of a conventional steam turbine. As shown in FIG. 6, the conventional steam turbine is provided on the steam turbine main body 51, the inlet side of the steam turbine main body 51, the control valve 52 for adjusting the amount of steam, and the upstream side of the control valve 52. And TTV 53 for controlling the supply of steam. The TTV 53 is provided with a hydraulic cylinder 54 for driving the valve body and a hydraulic cylinder 55 for emergency shutoff, and control oil is supplied to the

hydraulic cylinders

54 and 55 under the control of the adjustment device 56. By draining the control oil from 55, the TTV 53 is driven. Further, lubricating oil is supplied to the front bearing stand 51 a and the rear bearing stand 51 b of the steam turbine main body 51.

An accumulator 57 for accumulating control oil is provided in a connection pipe of control oil to the

hydraulic cylinders

54 and 55, and the control oil of the accumulator 57 can be supplied when necessary. The control oil supplied to the

hydraulic cylinders

54 and 55 is usually drained via the oil drain device 58 and, in a case of emergency, is drained via the emergency shut-off device 59 together with the oil drain device 58. The oil discharge device 58 is a parallel connection of oil discharge lines of the same configuration, and each oil discharge line includes a valve 58a, a valve 58b and an orifice 58c connected in parallel with the valve 58a, a valve 58a, and a valve A solenoid valve 58d is connected downstream of the orifice 58c and the orifice 58c. These devices are provided on the base plate 50.

As described above, in order to drive the TTV 53, auxiliary devices such as the

hydraulic cylinders

54 and 55, the adjusting device 56, the accumulator 57, the oil discharging device 58, and the emergency shutoff device 59 are connected to each other by piping. The packings and gaskets used for the connecting parts may cause an oil leak due to the aged deterioration, and there may also be a problem associated with the oil leak.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a main stop valve that does not perform hydraulic drive and a steam turbine provided with the main stop valve.

The main closing valve according to the first aspect of the invention for solving the above-mentioned problems is:
In the main stop valve that opens and closes the flow path through which the fluid flows,
A valve body for opening and closing the flow path by opening and closing an opening portion of a valve seat in the flow path;
A rod for linearly moving the valve body relative to the valve seat;
An electric actuator portion having a linearly moving piston;
The connection state changing unit changes the connection between the rod and the piston to the connection state or the disconnection state, and makes the rod and the piston to be in the connection state at times other than emergency. Do.

A main closing valve according to a second aspect of the invention for solving the above-mentioned problems is:
In the main closing valve according to the first aspect of the invention,
And an urging force application unit having a spring receiver attached to the rod and a spring for applying an urging force in a valve closing direction to the spring receiver.
At the time of emergency, the connection state change unit disconnects the rod and the piston from each other, and the biasing force application unit linearly moves the rod by the biasing force of the spring. The opening of the valve seat is closed by the valve body.

The main closing valve according to the third invention for solving the above-mentioned problems is:
In the main closing valve according to the first or second invention,
The connection state change unit is
A sleeve for holding the rod;
A holder for slidably holding the sleeve;
A latch for changing the holding state between the sleeve and the holder;
A lever for changing the position of the latch;
And an actuator for driving the lever.

The main closing valve according to the fourth invention for solving the above-mentioned problems is:
In the main closing valve according to the third aspect of the invention,
The actuator is an air cylinder.

A main closing valve according to a fifth aspect of the present invention for solving the above-mentioned problems,
In the main stop valve according to any one of the first to fourth inventions,
The electric actuator unit
A servomotor that performs rotational movement by supplying power;
Handles that rotate manually, and
A gear mechanism for transmitting the rotational movement of the servomotor or the rotational movement of the handle;
The rotary motion transmitted to the gear mechanism may be converted into linear motion, and the cylinder may move the piston linearly.

A steam turbine according to a sixth aspect of the present invention for solving the above-mentioned problems is:
The main closing valve according to any one of the first to fifth inventions is provided.

According to the present invention, since the conventional hydraulic cylinder for driving the valve body is changed to the electric actuator unit, the additional equipment necessary for supply and discharge of the control oil becomes unnecessary, and the cost of the steam turbine can be reduced. Thus, the weight of the apparatus can be reduced.

In addition, since the electric actuator unit with excellent control response is used to drive the main closing valve, the valve body can be opened and closed quickly, and control by an external signal is possible. Automatic startup, remote control, status monitoring, etc. are also possible.

In addition, since the above-mentioned incidental facility is not required, the field operation such as oil flushing operation and filter element replacement required for the conventional incidental facility can be omitted, man-hours can be shortened and maintenance can be improved. Problems such as oil leaks and debris that occur are eliminated.

It is a perspective view showing an example of an embodiment of a main closing valve concerning the present invention. It is a figure explaining the valve closing state at the time of the normal time of the main closing valve shown in FIG. 1, and showing the state of a valve while showing a part in section. It is a figure explaining the valve open state of the main stop valve shown in FIG. 1, and showing the state of a valve while showing a part in section. It is a figure explaining the valve closing state at the time of the emergency interruption | blocking of the main closing valve shown in FIG. 1, and showing the state of a valve body while showing a part in a cross section. It is the schematic explaining the structure of the steam turbine provided with the main stop valve shown in FIG. It is the schematic explaining the structure of the steam turbine provided with the conventional main closing valve.

Hereinafter, an embodiment of the main closing valve according to the present invention will be described with reference to FIGS. 1 to 5. In addition, although a vapor | steam is illustrated and demonstrated as an example of a fluid here, the main stop valve itself can also use another fluid.

Example 1
The main closing valve of the present embodiment will be described with reference to FIGS. 1 to 4. Here, FIG. 1 is a perspective view of the main closing valve of the present embodiment, and FIGS. 2 to 4 are views for explaining the open / close state of the main closing valve shown in FIG. FIG. 3 is a view showing a valve close state in a normal state, FIG. 3 is a view showing the valve open state, and FIG. 4 is a view showing the valve close state in the emergency shutoff.

As shown in FIG. 5 described later, the TTV 10 of the present embodiment is provided on the inlet side of the steam turbine main body 41, and opens and closes a flow path through which steam flows. The TTV 10 has a supply port 11, a valve chamber 12, a discharge port 13, and a valve drive unit 14. Inside the valve chamber 12, a valve seat 15 is formed in the middle of a flow path of steam, and a valve body 16 is provided opposite to the valve seat 15. The valve body 16 is driven by the valve body drive unit 14 to bring the valve body 16 into contact with the valve seat 15 and close the opening of the valve seat 15 to close the steam flow path (valve closed state), By separating the valve body 16 from the valve seat 15 and opening the opening of the valve seat 15, the steam flow path is opened (valve open state). Therefore, the vapor supplied to the supply port 11 is controlled by the valve body 16, and in the valve open state, the vapor is discharged from the exhaust port 13.

The valve body drive unit 14 includes a biasing force application unit 17, a connection state change unit 18, and an electric actuator unit 19. The biasing force application unit 17 is attached so that an end portion on the valve chamber 12 side is connected to the valve body 16 and a rod 21 for moving the valve body 16 linearly with respect to the valve seat 15 and the rod 21 penetrate in the axial direction D The spring receiver 22 and the end on the valve chamber 12 side are in contact with the spring receiver 22 and the spring 23 applies an urging force in the valve closing direction Dc, and the end on the connection state changing portion 18 side of the spring 23 is And a cylindrical support cylinder 24 slidably held in the axial direction D by being abutted.

Further, the connection state change unit 18 changes the state between the rod 21 and the piston 31a described later to a connection state or a non-connection state. Specifically, the connection state changing unit 18 includes a sleeve 25 that holds an end of the rod 21 on the connection state changing unit 18 side, a holder 26 that holds the sleeve 25 slidably in the axial direction D, and a sleeve 25. The latch 27 for changing the holding state between the and the holder 26, the lever 28 for rotating the latch 27 to change the position of the latch 27, and the air cylinder 29 for driving the lever 28 by the vertical movement in FIG. An actuator) and a support frame 30 provided outside the holder 26 and provided with an opening 30a that allows visual observation of the position of the rod 21, the sleeve 25, and the holder 26. Here, the conventional hydraulic cylinder for emergency cutoff is changed to the air cylinder 29.

Two latches 27 are provided at mutually opposing positions and extend in a direction perpendicular to the axial direction D and have a semicircular cross-sectional shape, with the semicircular surface side facing outward and the plane side facing inward. Corresponding to the latch 27, a recess 26a of a semicircular cross section is formed on the inner peripheral side of the holder 26, and the latch 27 is rotatably held in the circumferential direction. On the other hand, on the outer peripheral side of the sleeve 25, a notch 25a is formed in which the end of the latch 27 on the side of the electric actuator portion 19 engages. The latch 27 rotates in one direction and engages with the notch 25a, so that the sleeve 25 is held by the holder 26, rotates in the other direction, and disengages from the notch 25a. 25 is not held by the holder 26.

Further, in the electric actuator unit 19, the piston 31a is connected to the end of the holder 26 on the electric actuator unit 19 side, and the rotational motion is converted into a linear motion by a ball screw to linearly move the piston 31a in the axial direction D. The cylinder 31, the gear mechanism 32 for transmitting the rotational motion to the cylinder 31, and rotating the ball screw, and the servomotor 33 for rotating the gear mechanism 32 by performing the rotational motion by supplying power, the rotational motion manually , And a support base 35 for supporting the cylinder 31, the gear mechanism 32, and the servomotor 33. As shown in FIG. That is, the conventional hydraulic cylinder for driving the valve body is changed to the electric actuator unit 19.

The operation of the TTV 10 having the above configuration will be described with reference to FIG. 1 as well as FIGS. 2 to 4.

FIG. 2 is a view showing the valve closed state at the normal time (other than the emergency), and FIG. 3 is a view showing the valve open state. Under normal conditions, instrumentation air is supplied to the air cylinder 29, whereby the lever 28 is driven to rotate the latch 27 in the direction of meshing with the notch 25a, and the latch 27 is meshed with the notch 25a. As a result, the sleeve 25 is held by the holder 26 via the latch 27 engaged with the notch 25a. That is, the rod 21 and the piston 31a are in a connected state.

In the above-mentioned state, when the cylinder 31 is driven by the servomotor 33 (or the handle 34) via the gear mechanism 32 to move the piston 31a in the valve closing direction Dc, the holder 26 also moves in the same direction. With the movement of 26, the sleeve 25 and the rod 21 move in the same direction to bring the valve body 16 into contact with the valve seat 15 to close the valve and shut off the supply of steam (see FIG. 2). ).

In the above-mentioned state, when the cylinder 31 is driven by the servomotor 33 (or the handle 34) via the gear mechanism 32 to move the piston 31a in the valve opening direction Do, the holder 26 also moves in the same direction. As the holder 26 moves, the sleeve 25 and the rod 21 also move in the same direction to move the valve body 16 away from the valve seat 15 to open the valve and supply steam (see FIG. 3).

In the valve open state shown in FIG. 3, the spring 23 is pressed against the end of the support cylinder 24 by the spring receiver 22 and is in a contracted state. In such a state, when the instrumentation air supplied to the air cylinder 29 is drained as a drain, the air cylinder 29 is actuated to drive the lever 28 so that the engagement is released from the notch 25a. As a result, the engagement of the latch 27 with the notch 25 a is released, and the sleeve 25 is not held by the holder 26. That is, the rod 21 and the piston 31a are in a non-connected state. Then, the sleeve 25 and the rod 21 move in the valve closing direction Dc by the biasing force of the spring 23 to bring the valve body 16 into contact with the valve seat 15, thereby closing the valve and interrupting the supply of steam. (See FIG. 4).

That is, when there is an emergency or failure, for example, when the steam turbine body 41 has an abnormality or failure, or if the cylinder 31 or the servomotor 33 has an abnormality or failure, the instrumentation air supplied to the air cylinder 29 is drained as a drain. Thus, the supply of steam from the TTV 10 can be shut off promptly. The supply of instrumentation air to the air cylinder 29 is performed by a solenoid valve 43 shown in FIG. 5 described later, and the valve body 16 of the TTV 10 can be closed by controlling the solenoid valve 43 by an external signal.

When the valve is opened as shown in FIG. 3 after the valve closed state shown in FIG. 4, the cylinder 31 is driven by the servomotor 33 (or the handle 34) via the gear mechanism 32 to move the piston 31a to the valve The holder 26 is moved to the position where the latch 27 can be engaged with the notch 25 a of the sleeve 25 by moving in the closing direction Dc. After moving to the meshable position, when the instrumented air is supplied to the air cylinder 29, the air cylinder 29 operates, the lever 28 is driven, and the latch 27 rotates in the direction of meshing with the notch 25a. Mesh with the notch 25a. As a result, the sleeve 25 is held by the holder 26 via the latch 27 engaged with the notch 25a.

Thereafter, when the cylinder 31 is driven by the servomotor 33 (or the handle 34) via the gear mechanism 32 to move the piston 31a in the valve opening direction Do, the holder 26 also moves in the same direction, and the holder 26 moves. Accordingly, the sleeve 25 and the rod 21 are also moved in the same direction to separate the valve body 16 from the valve seat 15 to open the valve and supply steam (see FIG. 3).

FIG. 5 is a schematic view illustrating the configuration of a steam turbine provided with the TTV 10 described above. As shown in FIG. 5, the steam turbine of the present embodiment is provided on the steam turbine main body 41 and the inlet side of the steam turbine main body 41, and is provided on the control valve 42 for adjusting the amount of steam and on the upstream side of the control valve 42. And control the supply of steam.

As described above, the TTV 10 is provided with the electric actuator unit 19 for driving the valve body, the air cylinder 29 for emergency cutoff, and the like. The electric actuator unit 19 can drive the cylinder 31 by inputting an external signal to the servomotor 33, and the air cylinder 29 controls the solenoid valve 43 by the external signal to measure the amount in the air cylinder 29. It is possible to supply or discharge air. That is, by controlling the electric actuator unit 19 and the air cylinder 29, the TTV 10 can be driven. Further, lubricating oil is supplied to the front bearing stand 41 a and the rear bearing stand 41 b of the steam turbine main body 41. These devices are provided on the base plate 40.

Comparing the configuration of the steam turbine of the present embodiment shown in FIG. 5 with the configuration of the conventional steam turbine shown in FIG. 6, the conventional hydraulic cylinder 54 for driving the valve body is changed to the electric actuator unit 19. Since the conventional hydraulic cylinder 55 for emergency shutoff is changed to the air cylinder 29, incidental facilities (adjusting device 56, accumulator 57, discharge unit 58, emergency shutoff device 59) necessary for supply and discharge of control oil are used. It becomes unnecessary, and in addition, a pump for control oil etc. becomes unnecessary. Furthermore, because a relatively high hydraulic pressure control oil is not used, piping etc. that can withstand high hydraulic pressure are also unnecessary. In other words, it is possible to make an oil-less device that does not require oil other than the lubricating oil of the bearing. As a result, the apparatus cost of the steam turbine can be reduced by about 10%, and the apparatus weight can also be reduced.

Further, since the electric actuator unit 19 having excellent control response is used for driving the TTV 10, the valve body 16 can be opened and closed quickly, and control by an external signal is possible. It also enables startup, remote control and status monitoring. For example, when the steam turbine is automatically started, the opening degree of the valve body 16 of the TTV 10 may be appropriately changed by control based on an external signal in accordance with a change (rise) of the turbine rotational speed.

The present invention is suitable for a steam turbine that drives a compressor or the like.

10 TTV
14 valve body drive unit 16 valve body 17 biasing force application unit 18 connection state change unit 19 electric actuator unit 21 rod 22 spring support 23 spring 25 sleeve 26 holder 27 latch 29 air cylinder 31 cylinder 33 servo motor 41 steam turbine main body 43 solenoid valve

Claims

In the main stop valve that opens and closes the flow path through which the fluid flows,
A valve body for opening and closing the flow path by opening and closing an opening portion of a valve seat in the flow path;
A rod for linearly moving the valve body relative to the valve seat;
An electric actuator portion having a linearly moving piston;
The connection state changing unit changes the connection between the rod and the piston to the connection state or the disconnection state, and makes the rod and the piston to be in the connection state at times other than emergency. Main closing valve.
In the main closing valve according to claim 1,
And an urging force application unit having a spring receiver attached to the rod and a spring for applying an urging force in a valve closing direction to the spring receiver.
At the time of emergency, the connection state change unit disconnects the rod and the piston from each other, and the biasing force application unit linearly moves the rod by the biasing force of the spring. A main closing valve characterized in that an opening portion of a valve seat is closed by the valve body.
In the main closing valve according to claim 1 or 2,
The connection state change unit is
A sleeve for holding the rod;
A holder for slidably holding the sleeve;
A latch for changing the holding state between the sleeve and the holder;
A lever for changing the position of the latch;
And an actuator for driving the lever.
In the main closing valve according to claim 3,
The main closing valve is characterized in that the actuator is an air cylinder.
The main closing valve according to any one of claims 1 to 4,
The electric actuator unit
A servomotor that performs rotational movement by supplying power;
Handles that rotate manually, and
A gear mechanism for transmitting the rotational movement of the servomotor or the rotational movement of the handle;
And a cylinder configured to convert the rotational motion transmitted to the gear mechanism into a linear motion to linearly move the piston.
A steam turbine comprising the main stop valve according to any one of claims 1 to 5.