STEAM VALVE AND ENERGY GENERATION SYSTEM

Abstract

A steam valve according to at least one embodiment of the present disclosure comprises a valve body having a flow path separator section that separates a steam flow path through which steam flows, and a valve seat that is provided at a center of the steam flow path and has an opening section. The steam valve according to at least one embodiment of the present disclosure comprises a shut-off valve. The shut-off valve includes a valve stem that extends in an axial direction along which an axis extends and is configured to move forward and backward in the axial direction. The shut-off valve includes a secondary valve that is attached to a tip end of the valve stem of a tip end section of the valve stem.The shut-off valve comprises a main valve with a penetrating section into which a portion of the tip end of the valve stem is inserted. This section, positioned relative to the tip end on a base end of the valve stem, closes the steam flow path by bearing against the valve seat and forms a through-hole through which steam flows when the secondary valve is open. The shut-off valve includes a guide section that is axially movable with the main valve and guides a side face of the secondary valve so that it is displaceable along the axial direction.

Description

Technical area

[0001] The present disclosure relates to a steam valve and a power generation system.

[0002] This application claims priority based on Japanese Patent Application No. 2022-128695 filed in Japan on August 12, 2022, the contents of which are incorporated herein by reference. State of the art

[0003] For example, in a power generation system using a steam turbine, an amount of steam to be supplied to drive the steam turbine is adjusted in response to a load change, or a steam valve for shutting off the supply of steam to the steam turbine in the event of an abnormality is used. Typically, the steam valve is configured to include a valve seat having an opening portion, a valve rod that moves a valve body provided to face the opening portion of the valve seat in a direction of contact and separation of the valve body with respect to the valve seat, and a cylindrical bearing member that slidably supports the valve rod. In the steam valve having such a configuration, it is important to suppress abrasion of the valve body due to rotation or rattling of the valve body caused by steam.

[0004] Patent Publication No. 1 (PTL) is a structural example of this type of steam valve. Patent Publication No. 1 (PTL) discloses a steam valve (main steam shutoff valve) for a steam turbine in which a plane of a valve body (a surface parallel to the axial direction of a valve rod) and a plane of the valve rod (a surface parallel to the axial direction of the valve rod) are brought into surface contact with each other in a fitting portion between the valve body and the valve rod. Citation listPatent literature

[0005] [PTL 1] Japanese Unexamined Patent Application Publication No. 2014-70513 Summary of the inventionTechnical problem

[0006] Some steam valves include a shut-off valve including a valve rod, a sub-valve disposed at a tip end of the valve rod, and a main valve having a through-hole through which steam flows when the sub-valve is opened (a configuration corresponding to the valve body disclosed in PTL 1). In such a steam valve, since the sub-valve connected to an actuator is opened before the main valve, the through-hole provided in the main valve is opened to reduce the differential pressure between the upstream and downstream portions of the main valve, and the opening operation of the main valve is facilitated.

[0007] In the steam valve having the above configuration, from the viewpoint of suppressing the abrasion of the shut-off valve, it is important to support the main valve so that the main valve does not rotate or swing with respect to the valve rod in a state where the sub-valve and the main valve are open. However, in the valve structure disclosed in PTL 1, the fitting portion between the valve rod and the valve body is configured so that the planes of the valve rod and the valve body are adjusted to contact each other, and the distance of the valve rod in the axial direction on the plane is relatively short. Therefore, it is difficult to support the main valve so that it does not swing and tilt with respect to the axial direction in a state where the main valve is open.Therefore, in a state where the main valve is open, the main valve may swing with respect to the valve rod, and thus abrasion may occur in the shut-off valve.

[0008] An object of at least one embodiment of the present disclosure is to provide a steam valve and a power generation system capable of suppressing abrasion of a shut-off valve in a state where the shut-off valve is opened in view of the circumstances described above. Solution to the problem

[0009] (1) A steam valve according to at least one embodiment of the present disclosure comprises: a valve body having a flow path separating portion that separates a steam flow path through which steam flows, and a valve seat provided in a center of the steam flow path and having an opening portion; and a shut-off valve, and the shut-off valve contains: a valve rod extending in an axial direction along which an axis extends and configured to move forward and backward in the axial direction, a sub-valve attached to a tip end of the valve rod of a tip end portion of the valve rod, a main valve including a penetrating portion into which a portion of the tip end portion of the valve rod positioned on a base end side of the valve rod with respect to the tip end is inserted, which closes the steam flow path by abutting against the valve seat, and in which a through hole through which steam flows in a case where the sub-valve is opened is formed, and a guide portion movable in the axial direction together with the main valve and guiding a side surface of the sub-valve to be displaceable along the axial direction.

[0010] (2) A power generation system according to at least one embodiment of the present disclosure comprises: the steam valve having the configuration of the above (1); a boiler that generates steam; a steam turbine driven by the steam; and a steam supply pipe that connects the boiler and the steam turbine and supplies steam to the steam turbine, and The steam valve is provided on the steam supply pipe. Advantageous effects of the invention

[0011] According to at least one embodiment of the present disclosure, in a state where the shut-off valve is opened, it is possible to suppress the abrasion of the shut-off valve. Brief description of the drawings Fig. 1 is a schematic configuration diagram of a power generation system according to an embodiment. Fig. 2 is a cross-sectional view showing a configuration of a steam valve according to the embodiment in a state where a main valve and a sub-valve are in a closed state. Fig. Figure 3A is an enlarged view of area A of Fig. 2. Fig. 3B is a schematic view showing a state in which the sub-valve is opened first while the main valve remains in the closed state, in the steam valve according to the Fig. 3A shows the embodiment shown. Fig. Figure 4A is a schematic view showing an enlarged view of area A in Fig. 2, for the steam valve according to another embodiment. Fig. 4B is a schematic view showing a state in which the sub-valve is opened first while the main valve remains in the closed state, in the steam valve according to another embodiment of the present invention. Fig. 4A shows the embodiment shown. Fig. 4C is a schematic view of a bearing element in the steam valve according to another Fig. 4A when viewed from a tip end side in an axial direction. Description of embodiments

[0012] Some embodiments of the present disclosure will be described below with reference to the accompanying drawings. However, the sizes, materials, shapes, and relative arrangements of components described as the embodiments or illustrated in the drawings are not intended to limit the scope of the present disclosure and are merely examples for describing the present disclosure.

[0013] For example, expressions representing relative or absolute arrangements, such as "in a certain direction", "along a certain direction", "parallel", "perpendicular", "center", "concentric", or "coaxial", not only strictly represent the arrangements, but also a state in which the arrangements are relatively shifted with a tolerance or by an angle or distance, as long as the same function can be obtained.

[0014] For example, expressions that represent things being in a same state, such as "identical," "equal," and "homogeneous," represent not only strictly a same state, but also a state in which a difference exists with a tolerance or to such an extent that the same function can be obtained.

[0015] For example, expressions representing shapes such as a quadrangular shape and a cylindrical shape represent not only shapes such as a quadrangular shape and a cylindrical shape in a geometrically strict sense, but also shapes including an uneven portion or a chamfer portion within a range where the same effect can be obtained.

[0016] Furthermore, expressions such as “provided with,” “equipped with,” “containing,” or “having” a component are not exclusionary expressions that exclude the presence of other components. (Overall configuration of power generation system)

[0017] First, a power generation system 1 to which a steam valve 14 according to at least one embodiment of the present disclosure is applied will be described. Fig. 1 is a schematic configuration diagram of a power generation system 1 according to an embodiment. The power generation system 1 includes a steam turbine 10, a boiler 11, and a generator 26.

[0018] The steam turbine 10 is a turbine driven by steam generated in the boiler 11. The steam turbine 10 is connected to the boiler 11 through a first steam supply pipe 12 and is driven by supplying high-pressure steam generated by burning fuel in the boiler 11. A steam valve 14 for adjusting a flow rate of steam supplied to the steam turbine 10 is provided at the first steam supply pipe 12. The configuration of the steam valve 14 includes a throttle valve 43 and a shutoff valve 45, which will be described later.

[0019] In the present embodiment, a multi-stage turbine is exemplified as the steam turbine 10, and the steam turbine 10 includes a high-pressure steam turbine 31, a medium-pressure steam turbine 32, and a low-pressure steam turbine 33 from the upstream side with respect to the steam flow path. The high-pressure steam turbine 31 is driven by the steam (high-pressure steam generated by the boiler 11) supplied from the first steam supply pipe 12. The steam that has completed the work in the high-pressure steam turbine 31 is supplied to the medium-pressure steam turbine 32 through the second steam supply pipe 16. A reheater 18 is provided at the second steam supply pipe 16.

[0020] The medium-pressure steam turbine 32 is driven by the steam (the steam that has completed the work in the high-pressure steam turbine 31) supplied from the second steam supply pipe 16. The steam that has completed the work in the medium-pressure steam turbine 32 is supplied to the low-pressure steam turbine 33 through the third steam supply pipe 25. The low-pressure steam turbine 33 is driven by the steam (the steam that has completed the work in the medium-pressure steam turbine 32) supplied from the third steam supply pipe 25.

[0021] Each turbine (the high-pressure steam turbine 31, the medium-pressure steam turbine 32, and the low-pressure steam turbine 33) constituting the steam turbine 10 has a common rotating shaft 35. The generator 26 is connected to the rotating shaft 35, and the generator 26 is driven by the rotation of each turbine to perform power generation. (Configuration of steam valve 14)

[0022] Next, the configuration of the steam valve 14 according to some embodiments will be described with reference to the drawings.

[0023] Fig. 2 is a cross-sectional view showing a configuration of the steam valve 14 according to the embodiment in a state where the main valve 64 and the sub-valve 62 are in a closed state.

[0024] Fig. Figure 3A is an enlarged view of area A of Fig. 2.

[0025] Fig. 3B is a schematic view showing a state in which the sub-valve 62 is opened first while the main valve 64 remains in the closed state, in the steam valve 14 according to the Fig. 3A shows the embodiment shown.

[0026] Fig. Figure 4A is a schematic view showing an enlarged view of area A in Fig. 2, for the steam valve 14 according to another embodiment.

[0027] Fig. 4B is a schematic view showing a state in which the sub-valve 62 is opened first while the main valve 64 remains in the closed state, in the steam valve 14 according to another embodiment of the present invention. Fig. 4A shows the embodiment shown.

[0028] Fig. 4C is a schematic view of a bearing element 80 in the steam valve 14 according to another embodiment of the invention. Fig. 4A when viewed from a tip end side in an axial direction Z.

[0029] In Fig. 2 and 3A to 4B, O1 is an axis of the valve rod 61 constituting the shut-off valve 45, and O2 is an axis of the valve rod 55 constituting the throttle valve 43. A direction in which the axes O1 and O2 extend (hereinafter referred to as an "axial direction Z") is, for example, a substantially vertical direction. In Fig. 2A to 4B, for example, the top side in the drawings is the top side in a substantially vertical direction, and the bottom side in the drawings is, for example, the bottom side in the substantially vertical direction.

[0030] As in Fig. 2, the steam valve 14 includes a valve body 41, a throttle valve 43, a shut-off valve 45, and actuators 46A and 46B. The valve body 41 includes a flow path separating portion 47 and a valve seat 48. The flow path separating portion 47 separates the steam flow path 52 and occupies a part of the tip end side (bottom side in Fig. 2) of the throttle valve 43 and part of the tip end side (top in Fig. 2) of the shut-off valve 45. The steam flow path 52 includes an inlet portion 52A and an outlet portion 52B. The inlet portion 52A is connected to the boiler 11 through one side of the first steam supply pipe 12, and high-pressure steam generated in the boiler 11 is supplied thereto. The outlet portion 52B is connected to the high-pressure steam turbine 31 through the other side of the first steam supply pipe 12. The amount of steam supplied from the boiler 11 to the high-pressure steam turbine 31 through the first steam supply pipe 12 can be adjusted by controlling the opening degree of the throttle valve 43 in the steam valve 14 provided in the first steam supply pipe 12 in a state where the shut-off valve 45 is opened.

[0031] The flow path separation portion 47 includes a first guide member 47A and a second guide member 47B. The first guide member 47A is provided to cover an outer peripheral surface of a portion, not exposed to the steam flow path 52, of the valve rod 55 constituting the throttle valve 43. The first guide member 47A functions as a guide that guides the valve rod 55 in the axial direction Z. The second guide member 47B is provided to cover an outer peripheral surface of the base end portion 61B of the valve rod 61 constituting the shut-off valve 45. The second guide member 47B functions as a guide that guides the valve rod 61 in the axial direction Z.

[0032] The valve seat 48 is provided in the flow path separation section 47, which is positioned at the center of the steam flow path 52. The valve seat 48 has an annular shape centered on the axis O1 and is configured so that the axis of the valve seat 48 coincides with the axis O1. The valve seat 48 has a valve seat surface 48a exposed to the steam flow path 52. The valve seat surface 48a is, for example, a curved surface. The valve seat surface 48a is configured to abut against both the main valve 64 constituting the shut-off valve 45 and a tip end 56A of a throttle valve body 56 constituting the throttle valve 43. (Throttle valve 43)

[0033] The throttle valve 43 is arranged upstream of a position where the shut-off valve 45 is arranged, in a flow direction of the steam. The throttle valve 43 includes a valve rod 55 and a throttle valve body 56. The valve rod 55 extends in the axial direction Z, and a tip end thereof is arranged in the steam flow path 52. The axis O2 of the valve rod 55 is configured to coincide with the axis O1 of the valve rod 61 of the shut-off valve 45. The valve rod 55 can be moved in the axial direction Z.

[0034] The throttle valve body 56 is formed on a tip end side (bottom side in Fig. 2) of the valve rod 55. A portion of the throttle valve body 56, which is on the side of the valve seat 48 (bottom in Fig. 2) is positioned, has a tubular shape and has a tip end 56A that can abut against the valve seat surface 48a of the valve seat 48. The throttle valve 43 having such a configuration has a function of adjusting the flow rate of the high-pressure steam supplied to the high-pressure steam turbine 31 in accordance with the load of the steam turbine 10 by controlling the distance between the tip end 56A of the throttle valve body 56 and the valve seat 48 by moving the valve rod 55 along the axial direction Z by the actuator 46A. (Shut-off valve 45)

[0035] The shut-off valve 45 is disposed within the throttle valve 43. The shut-off valve 45 is configured to include a valve rod 61, a sub-valve 62, a main valve 64, and a guide portion 65.

[0036] The valve rod 61 extends in the axial direction Z and includes a tip end portion 61A and a base end portion 61B.

[0037] In the following description of the shut-off valve 45, an upper side in the drawing along the axial direction Z is referred to as a tip end side of the valve rod 61 or simply as a tip end side, and a lower side in the drawing along the axial direction Z is referred to as a base end side of the valve rod 61 or simply as a base end side.

[0038] The tip end portion 61A has a shape capable of fitting with the sub-valve 62 for fixing the sub-valve 62. The base end portion 61B extends along the axial direction Z and has a constant outer diameter. The base end side of the base end portion 61B is connected to the actuator 46B. The valve rod 61, which includes the tip end portion 61A and the base end portion 61B, is integrally formed and can move forward and backward in the axial direction Z. (Side valve 62)

[0039] As in Fig. As shown in FIGS. 3A to 4B, in the steam valve 14 according to some embodiments, the sub-valve 62 includes a sub-valve body 621 constituting the sub-valve 62. The sub-valve body 621 according to some embodiments includes a large-diameter portion 623 and a small-diameter portion 625 having a diameter smaller than that of the large-diameter portion 623 and positioned closer to the tip end side than the large-diameter portion 623.

[0040] The sub-valve 62 according to some embodiments includes a recessed portion 62A and an abutment portion 62B. The recessed portion 62A has a shape corresponding to the tip end portion 61A of the valve rod 61 and fits with the tip end portion 61A so that the sub-valve 62 is fixed to the tip end portion 61A of the valve rod 61. In the sub-valve 62 according to some embodiments, the tip end portion 61A of the valve rod 61 is configured in a screw shape, and the recessed portion 62A is configured as a screw hole corresponding to the tip end portion 61A. The tip end portion 61A of the valve rod 61 is inserted into the recessed portion 62A of the sub-valve 62, thereby fixing the sub-valve 62 to the valve rod 61.

[0041] As described above, since the recessed portion 62A formed in the sub-valve 62 is fitted to the tip end portion 61A of the valve rod 61, the sub-valve 62 is fixed to the valve rod 61. Therefore, the sub-valve 62 is prevented from swinging or rotating with respect to the valve rod 61. Accordingly, the abrasion between the sub-valve 62 and the valve rod 61 (the abrasion of the check valve 45) can be suppressed.

[0042] The lower portion of the large diameter portion 623 has a tapered surface 624 formed such that a diameter thereof decreases toward the base end side. The tapered surface 624 is provided with an abutment portion 62B. The abutment portion 62B is configured in a ring shape when viewed from the axial direction Z. In a state where the sub-valve 62 is closed (a Fig. 2, Fig. 3A and Fig. 4A), the abutment portion 62B is positioned on top of the through-hole 71B described below in the main valve body 71 constituting the main valve 64, and abuts against the sub-valve seat 71a provided on the main valve body 71. In this state, since the inlet 71Ba of the through-hole 71B is isolated from the steam flow path 52 through which the high-pressure steam flows, the high-pressure steam does not flow through the through-hole 71B.

[0043] In the steam valve 14 according to some embodiments, in a case where the flow rate of the steam is adjusted by the throttle valve 43, the shut-off valve 45 is opened before the throttle valve 43 is opened. At this time, the shut-off valve 45, as shown in Fig. 2, Fig. 3A and Fig. 4A, the sub-valve 62 from a state in which both the sub-valve 62 and the main valve 64 are closed, as shown in Fig. 3B and Fig. 4B, opened before the main valve 64 (the main valve 64 remains closed).

[0044] In this case, since the abutment portion 62B of the sub-valve 62 is separated from the sub-valve seat 71a, a gap is formed between the sub-valve 62 and the main valve 64, and thus high-pressure steam flows into the inlet 71Ba of the through-hole 71B.

[0045] At the steam valve 14 according to the Fig. 3B, the high-pressure steam flowing into the inlet 71Ba of the through-hole 71B is guided from the outlet 71Bb of the through-hole 71B to the steam flow path 52.

[0046] In the steam valve 14 according to another in Fig. 4B, the high-pressure steam flowing into the inlet 71Ba of the through-hole 71B is guided from the outlet 71Bb of the through-hole 71B through the through-hole 81B of the bearing member 80 described below to the steam flow path 52.

[0047] As a result, the differential pressure between the upstream side and the downstream side of the main valve 64 is reduced, and the subsequent opening operation of the main valve 64 is facilitated. (Main valve 64)

[0048] The main valve 64 is disposed between the sub-valve 62 and the base end portion 61B in a state where the main valve is inserted into the valve rod 61. The main valve 64 includes a main valve body 71. The main valve body 71 has a substantially V-shape when viewed from a vertical cross-sectional view. The main valve body 71 includes a penetrating portion 71A, a sub-valve seat 71a, an abutment surface 71b, an inner peripheral surface 71c, and a plurality of through holes 71B.

[0049] The penetrating portion 71A is formed to penetrate a central portion of the main valve body 71 in the axial direction Z. The penetrating portion 71A is a columnar hole and is separated by the inner peripheral surface 71c. The valve rod 61 is inserted into the penetrating portion 71A.

[0050] In the main valve 64 of the steam valve 14 according to some embodiments, the penetrating portion 71A is provided with a contact portion 713 that contacts the outer peripheral surface of the valve rod 61 on the base end side of the main valve 64 so as to be slidable.

[0051] At the main valve 64 of the steam valve 14 according to the Fig. 3A and Fig. 3B, the penetrating portion 71A is provided with a rectangular hole portion 711 configured to slidably fit a rectangular cross-sectional portion 61C having a rectangular cross-section of the valve rod 61.

[0052] In the main valve 64 of the steam valve 14 according to some embodiments, the contact portion 713 includes a build-up portion 713a. For example, a Stellite (registered trademark) alloy is used for the build-up portion 713a. The material of the main valve 64 provided with the build-up portion 713a is, for example, high-chromium steel such as 9Cr steel, and the material of the valve rod 61 slidably in contact with the build-up portion 713a is, for example, a nickel-based superalloy such as Inconel (registered trademark).

[0053] In the main valve 64 of the steam valve 14 according to some embodiments, the valve seat surface of the sub-valve seat 71a is a curved surface located on the sub-valve 62 side (tip end side of the valve rod 61). The valve seat surface of the sub-valve seat 71a abuts against the abutment portion 62B of the sub-valve 62 in a case where the sub-valve 62 is closed (see Fig. 2, Fig. 3A and Fig. 4A).

[0054] In the main valve 64 of the steam valve 14 according to some embodiments, the sub-valve seat 71a includes a structural portion 711a. For example, a Stellite (registered trademark) alloy is used for the structural portion 711a.

[0055] In the main valve 64 of the steam valve 14 according to some embodiments, the abutment surface 71b is a curved surface located on the base end side of the valve rod 61. In a state where the main valve 64 is fully closed, an outer peripheral portion of the abutment surface 71b abuts against the valve seat surface 48a of the valve seat 48. In this state, the high-pressure steam does not flow to the downstream side of the valve seat 48. On the other hand, in a state where the main valve 64 is opened, the abutment surface 71b and the valve seat surface 48a are separated from each other, and a gap is formed between the abutment surface 71b and the valve seat surface 48a. Therefore, high-pressure steam corresponding to the opening degree of the throttle valve 43 flows to the downstream side of the valve seat 48.

[0056] In the main valve 64 of the steam valve 14 according to some embodiments, a build-up portion 711b is formed on a portion of an outer peripheral portion of the abutment surface 71b that abuts against the valve seat 48. For example, a Stellite (registered trademark) alloy is used for the build-up portion 711b.

[0057] The main valve body 71 of the steam valve 14 according to another in Fig. 4A and Fig. 4B has a base end recessed portion 73 which is recessed from the base end side to the tip end side.

[0058] The base end side recessed portion 73 is separated by a bottom surface 731 facing the base end side and a peripheral wall portion 733 surrounding an outer edge of the bottom surface 731 in a circumferential direction around the axis O1.

[0059] The bottom surface 731 is configured to abut against a contact surface 81 facing the tip end side in a bearing member 80 described below.

[0060] An inner peripheral surface 735 of the peripheral wall portion 733 is configured to contact an outer peripheral surface 83 of a bearing member 80, which will be described later, so as to be slidable along the axial direction Z.

[0061] In the main valve body 71 of the steam valve 14 according to another in Fig. 4A and Fig. In the embodiment shown in Figure 4B, the build-up portion 731a is formed in an annular region on the outer side in the radial direction with respect to the axis O1 of the bottom surface 731. The build-up portion 731a is constructed, for example, with a nickel-based superalloy such as Inconel (registered trademark).

[0062] At the main valve 64 of the steam valve 14 according to the Fig. 3A and Fig. 3B, the plurality of through holes 71B are formed to penetrate the main valve body 71 from the inner peripheral surface 71c facing the space surrounded by the guide portion 65, which will be described later, to the bottom surface 715 of the main valve body 71.

[0063] In the main valve 64 of the steam valve 14 according to another in Fig. 4A and Fig. 4B, the plurality of through holes 71B are formed to penetrate the main valve body 71 from the curved surface 71d facing the space surrounded by the guide portion 65, which will be described later, to the bottom surface 731.

[0064] In the main valve 64 of the steam valve 14 according to some embodiments, the plurality of through holes 71B are arranged in the circumferential direction of the main valve body 71. Each through hole 71B has an inlet 71Ba and an outlet 71Bb.

[0065] At the main valve 64 of the steam valve 14 according to the Fig. 3A and Fig. 3B, the inlet 71Ba is formed on the base end side of the abutment position between the abutment portion 62B and the sub-valve seat 71a.

[0066] In the main valve 64 of the steam valve 14 according to another in Fig. 4A and Fig. 4B, the inlet 71Ba is formed on the inside in the radial direction from the abutment position between the abutment portion 62B and the sub-valve seat 71a at the curved surface 71d facing the space surrounded by the guide portion 65 described below.

[0067] Since the secondary valve 62 is opened before the main valve 64, as in Fig. 3B and Fig. 4B, and a gap is formed between the sub-valve 62 and the main valve 64, high-pressure steam flows through the inlet 71Ba into the through-hole 71B.

[0068] In the main valve 64 of the steam valve 14 according to some embodiments, the outlet 71Bb is formed in the bottom surface 715 or the bottom surface 731, which is positioned on the outside with respect to the axis O1 in the radial direction of the position where the inlet 71Ba is formed.

[0069] At the main valve 64 of the steam valve 14 according to the Fig. 3A and Fig. 3B, the outlet 71Bb communicates with the steam flow path 52 positioned on the downstream side of the valve seat 48.

[0070] In the main valve 64 of the steam valve 14 according to another in Fig. 4A and Fig. 4B, the outlet 71Bb communicates with the steam flow path 52 positioned on the downstream side of the valve seat 48 through a through hole 81B of a bearing member 80, which will be described later. (Guide Section 65)

[0071] In the main valve 64 of the steam valve 14 according to some embodiments, the guide portion 65 is configured to move in the axial direction Z together with the main valve 64 and to guide the side surface 62C of the sub-valve 62 to be slidable along the axial direction Z.

[0072] In the main valve 64 of the steam valve 14 according to some embodiments, the guide portion 65 may be a separate member from the main valve body 71 and may be fixed to the main valve body 71 by a fixing member such as a bolt (not shown) or may be formed integrally with the main valve body 71.

[0073] In the main valve 64 of the steam valve 14 according to some embodiments, the guide portion 65 has a tubular portion 66 surrounding the side surface 62C of the sub-valve 62 in the circumferential direction.

[0074] In the main valve 64 of the steam valve 14 according to another in Fig. 3A and Fig. 3B, an annular plate portion 67 including a facing surface 68 facing the base end side and opposing the large diameter portion 623 of the sub-valve 62 is provided on the tip end side of the tubular portion 66.

[0075] At the main valve 64 of the steam valve 14 according to the Fig. 3A and Fig. In the embodiment shown in Fig. 3B, a through hole 67h is formed penetrating the annular plate portion 67 in the axial direction Z. The small-diameter portion 625 of the sub-valve 62 is inserted into the through hole 67h. The outer peripheral surface of the small-diameter portion 625 is guided to be slidable relative to the inner peripheral surface 67i of the through hole 67h along the axial direction Z.

[0076] In the guide section 65 of the steam valve 14 according to the Fig. 3A and Fig. In the embodiment shown in FIG. 3B, the abutment portions 67a and 68a are formed at the contact portion with the sub-valve 62, that is, the inner peripheral surface 67i of the through-hole 67h and the facing surface 68. For example, a Stellite (registered trademark) alloy is used for the abutment portions 67a and 68a. The material of the guide portion 65 provided with the abutment portions 67a and 68a is, for example, a high-chromium steel such as 9Cr steel, and the material of the sub-valve 62 slidably in contact with and abutting against the abutment portion 67a is, for example, a nickel-based superalloy such as Inconel (registered trademark) as described above.

[0077] In the main valve 64 of the steam valve 14 according to another in Fig. 4A and Fig. In the embodiment shown in Fig. 4B, the large-diameter portion 623 of the sub-valve 62 is inserted into the tubular portion 66. The outer peripheral surface of the large-diameter portion 623 is guided along the axial direction Z so as to be slidable on the inner peripheral surface 66i of the tubular portion 66.

[0078] In a guide section 65 of the steam valve 14 according to another in Fig. 4A and Fig. In the embodiment shown in Fig. 4B, a build-up portion 66a is formed at the contact portion with the sub-valve, that is, an inner peripheral surface 66i of a tubular portion 66. For example, a Stellite (registered trademark) alloy is used for the build-up portion 66a. The material of the guide portion 65 provided with the build-up portion 67a is, for example, a high-chromium steel such as 9Cr steel, and the material of the sub-valve 62 slidably in contact with the build-up portion 66a is, for example, a nickel-based superalloy such as Inconel (registered trademark) as described above.

[0079] In the main valve 64 of the steam valve 14 according to some embodiments, the guide portion 65 is provided with a plurality of through holes 66h formed so that steam flows when the sub-valve 62 is opened and steam in the inlet portion 52A of the steam flow path 52 is released to the outlet portion 52B of the steam flow path 52. In the main valve 64 of the steam valve 14 according to some embodiments, the plurality of through holes 66h are formed, for example, in the tubular portion 66 so as to penetrate the tubular portion 66 in the radial direction. (Bearing element 80)

[0080] As in Fig. 4A, Fig. 4B and Fig. 4C, in the steam valve 14 according to another embodiment, the bearing member 80 is provided which is positioned on the base end side with respect to the main valve 64, is fixed to the valve rod 61, and has an abutment surface 81 capable of abutting against a bottom surface 731 facing the base end side of the main valve 64.

[0081] The bearing element 80 is configured such that, in a case where the main valve 64 is open, it abuts the contact surface 81 with the bottom surface 731 of the main valve 64 and supports the main valve 64.

[0082] The bearing element 80 has a substantially V-shape in a vertical cross-sectional view. The bearing element 80 has a bearing surface 81, a penetrating portion 81A, a plurality of through holes 81B, and a plurality of abrasive powder discharge holes 81C.

[0083] The penetrating portion 81A is formed to penetrate a central portion of the bearing member 80 in the axial direction Z. The valve rod 61 is inserted into the penetrating portion 81A.

[0084] The abutment surface 81 is a surface of the bearing member 80 facing the tip end side, and is an inclined surface inclined toward the inside in the radial direction centered on the axis O1 toward the base end side.

[0085] The plurality of through holes 81B includes an inlet 81Ba and an outlet 81Bb. The plurality of through holes 81B are arranged in the circumferential direction of the bearing member 80 such that the inlet 81Ba faces the outlet 71Bb of the plurality of through holes 71B of the main valve 64, and penetrate from the abutment surface 81 to the surface of the bearing member 80 on the base end side.

[0086] The plurality of abrasive powder discharge holes 81C are arranged in the circumferential direction of the bearing member 80 and penetrate from a recessed portion 81D recessed toward the base end side on the inner side in the radial direction of the abutment surface 81 to a surface of the bearing member 80 on the base end side.

[0087] A mounting portion 81a is formed in a region of the abutment surface 81 facing the mounting portion 731a provided on the bottom surface 731 of the main valve body 71. For example, a Stellite (registered trademark) alloy is used for the mounting portion 81a. Furthermore, the material of the bearing member 80 provided with the mounting portion 81a is, for example, high-chromium steel such as 9Cr steel.

[0088] An outer peripheral surface 83 of the bearing member 80 is configured to contact an inner peripheral surface 735 of the peripheral wall portion 733 of the main valve body 71 so as to be slidable along the axial direction Z.

[0089] As in Fig. 4C, the outer peripheral portion 85 of the bearing member 80 has a linear outer peripheral portion 85a formed in a linear shape when viewed along the axis O1. In the Fig. 4C, the linear outer peripheral portion 85a extends in a tangent direction centered on the axis O1. In the example shown in Fig. In the example shown in Fig. 4C, the linear outer peripheral portion 85a is provided at four positions at intervals of 90 degrees with respect to the axis O1.

[0090] A contact portion of the bearing member 80 and the peripheral wall portion 733 of the main valve body 71, that is, an outer peripheral portion 85 of the bearing member 80, is provided with a build-up portion 85b. For example, a Stellite (registered trademark) alloy is used for the build-up portion 85b.

[0091] In the steam valve 14 according to another in Fig. 4A, Fig. 4B and Fig. 4C, the main valve 64 is formed in a linear shape when viewed along the axis O1 at the peripheral wall portion 733 and has a linear inner peripheral portion 733a facing the linear outer peripheral portion 85a.

[0092] Therefore, in the steam valve 14 according to another in Fig. 4A, Fig. 4B and Fig. 4C, since each of the linear inner peripheral portions 733a and each of the linear outer peripheral portions 85a face each other so as to be displaceable relative to each other, the main valve 64 is prevented from being rotationally moved in the circumferential direction centered on the axis O1 with respect to the bearing member 80 fixed to the valve rod 61. Therefore, in the steam valve 14 according to another embodiment shown in Fig. 4A, Fig. 4B and Fig. 4C, the main valve 64 is prevented from being rotated in the circumferential direction centered on the axis O1 with respect to the valve rod 61. (Opening process of shut-off valve 45)

[0093] The opening operation of the shut-off valve 45 in the steam valve 14 according to some embodiments will be described.

[0094] As in Fig. 2, Fig. 3A and Fig. 4A, in the steam valve 14 according to some embodiments, in a case where the shut-off valve 45 is closed, the outer peripheral portion of the abutment surface 71b of the main valve body 71 and the valve seat surface 48a of the valve seat 48 come into contact with each other, and the abutment portion 62B of the sub-valve 62 and the sub-valve seat 71a of the main valve body 71 come into contact with each other.

[0095] In the steam valve 14 according to another in Fig. 4A, Fig. 4B and Fig. 4C, in a case where the shut-off valve 45 is closed, a bottom surface 731 of the main valve body 71 and a contact surface 81 of the bearing element 80 are separated from each other in the axial direction Z.

[0096] In a case where the valve rod 61 is driven toward the tip end side by the actuator 46B, the sub-valve 62 attached to the valve rod 61 moves toward the tip end side. Accordingly, high-pressure steam flows into the inlet 71Ba of the through hole 71B to be separated from the abutment portion 62B of the sub-valve 62 and the sub-valve seat 71a of the main valve body 71, and is guided to the steam flow path 52.

[0097] In the steam valve 14 according to another in Fig. 4A, Fig. 4B and Fig. 4C, in a case where the valve rod 61 is moved toward the tip end side by the actuator 46B, the bearing member 80 fixed to the valve rod 61 is moved toward the tip end side.

[0098] At the steam valve 14 according to the Fig. 3A and Fig. 3B is a case where the valve rod 61 is further driven toward the tip end side as shown in Fig. 3B, a surface 623u of the large-diameter portion 623 of the sub-valve 62 on the tip end side abuts against a facing surface 68 of an annular plate portion 67 of the guide portion 65 and pushes the facing surface 68 toward the tip end side. Accordingly, the guide portion 65 and the main valve body 71 to which the guide portion 65 is fixed are driven toward the tip end side, and the outer peripheral portion of the abutment surface 71b of the main valve body 71 and the valve seat surface 48a of the valve seat 48 are separated from each other, thereby opening the main valve.

[0099] In the steam valve 14 according to another in Fig. 4A, Fig. 4B and Fig. 4C is in a case where the valve rod 61 is further driven toward the tip end side as shown in Fig. 4B, the abutment surface 81 of the bearing member 80 abuts the bottom surface 731 of the main valve body 71 and pushes the main valve body 71 toward the tip end side. Accordingly, the main valve body 71 is driven toward the tip end side, and the outer peripheral portion of the abutment surface 71b of the main valve body 71 and the valve seat surface 48a of the valve seat 48 are separated from each other to open the main valve. (On excitation and abrasion of main valve 64)

[0100] In a case where the steam valve 14 is opened and closed, the flow rate of steam is adjusted by adjusting the opening degree of the throttle valve 43 after the opening operation is performed in the order of the sub-valve 62 and the main valve 64 at the shut-off valve 45 as described above.

[0101] Here, in a case where the throttle valve 43 is opened in a closed state from a state where the sub-valve 62 and the main valve 64 are in the open state, particularly in a case where the opening degree of the throttle valve 43 is small, the inflow rate of steam to the shut-off valve 45 is increased. In this case, the main valve 64 is energized by the inflowing steam, and there is a concern that abrasion may occur.

[0102] On the other hand, in the steam valve 14 according to some embodiments described above, the base end side of the main valve 64 is supported by the valve rod 61 so as to be slidable in the penetrating portion 71A, and at the tip end side of the main valve 64, the guide portion 65, which is movable together with the main valve 64, is supported by the sub-valve 62 at the tip end of the valve rod 61. Accordingly, the distance in the axial direction Z between the position P1 where the main valve 64 is supported on the base end side of the valve rod 61 and the position P2 where the main valve 64 is supported on the tip end side of the valve rod 61 can be relatively large. Therefore, in a state where the shut-off valve 45 is opened, the movement of the swinging of the main valve 64 so as to be inclined with respect to the axial direction Z can be easily suppressed.Therefore, it is possible to suppress the abrasion of the shut-off valve 45 in a state where the shut-off valve 45 is opened.

[0103] In the steam valve 14 according to some embodiments, the guide portion 65 guides the side surface 62C of the sub-valve 62 so as to be slidable with respect to the sub-valve seat 71a at a position on the tip end side of the valve rod 61 along the axial direction Z.

[0104] Accordingly, the position P2 where the main valve 64 is supported on the tip end side of the valve rod 61 can be provided relatively on the tip end side of the valve rod 61. Accordingly, the distance in the axial direction Z between the position P1 where the main valve 64 is supported on the base end side of the valve rod 61 and the position P2 where the main valve 64 is supported on the tip end side of the valve rod 61 can be relatively large.

[0105] At the steam valve 14 according to the Fig. 3A and Fig. 3B, the guide portion 65 is configured to guide the side surface of the small diameter portion 625 so as to be slidable along the axial direction Z.

[0106] Accordingly, the position P2 where the main valve 64 is supported on the tip end side of the valve rod 61 can be provided relatively on the tip end side of the valve rod 61. Accordingly, the distance in the axial direction Z between the position P1 where the main valve 64 is supported on the base end side of the valve rod 61 and the position P2 where the main valve 64 is supported on the tip end side of the valve rod 61 can be relatively large.

[0107] At the steam valve 14 according to the Fig. 3A and Fig. 3B, the facing surface 68 is configured to abut the large diameter portion 623 in a case where the sub-valve 62 is open.

[0108] Accordingly, the large-diameter portion 623 abuts against the facing surface 68 to press the facing surface 68, and the guide portion 65 and the main valve 64 (main valve body 71) are moved toward the tip end side, whereby the main valve 64 can be opened. Accordingly, the valve opening mechanism of the main valve 64 can be realized by a relatively simple structure.

[0109] In the steam valve 14 according to some embodiments, the penetrating portion 71A may include a structural portion 713a constructed with a material different from the material of the penetrating portion 71A (i.e., the main valve body 71) and the valve rod 61, at the contact portion 713 between the penetrating portion 71A and the valve rod 61.

[0110] In the steam valve 14 according to some embodiments, the guide portion 65 may have a structural portion 67a or a structural portion 66a constructed with a material different from the material of the guide portion 65 and the sub-valve 62 on the inner peripheral surface 67i of the through-hole 67h, which is the contact portion between the guide portion 65 and the sub-valve 62, or the inner peripheral surface 66i of the tubular portion 66.

[0111] Accordingly, it is possible to suppress the abrasion of the contact portion 713 and the abrasion of the inner peripheral surface 67i or the inner peripheral surface 66i.

[0112] In the steam valve 14 according to another in Fig. 4A, Fig. 4B and Fig. 4C, the bearing member 80 is configured so that, in a case where the main valve 64 is open, the abutment surface 81 abuts against the bottom surface 731 of the main valve 64 to support the main valve 64. Accordingly, since the area of ​​the abutment surface 81 can be relatively easily increased, it is easy to suppress the surface pressure in a case where the abutment surface 81 abuts against the bottom surface 731 of the main valve 64, and it is easy to suppress the abrasion of the abutment surface 81 and the bottom surface 731 of the main valve 64 against which the abutment surface 81 abuts.

[0113] In the steam valve 14 according to another in Fig. 4A, Fig. 4B and Fig. 4C, the abutment area R of the abutment surface 81 and the bottom surface 731 of the main valve 64 may include an area located further to the outside in the radial direction than the position on the outermost side in the radial direction centered on the axis O1 at the sub-valve 62.

[0114] Accordingly, since the area of ​​the abutment surface 81 is relatively large, the surface pressure in a case where the abutment surface 81 abuts against the bottom surface 731 of the main valve 64 can be suppressed, and it is possible to suppress the abrasion of the abutment surface 81 and the bottom surface 731 of the main valve 64 against which the abutment surface 81 abuts.

[0115] In the steam valve 14 according to another in Fig. 4A, Fig. 4B and Fig. 4C, the abutment surface 81 is an inclined surface inclined toward the inside in the radial direction toward the base end side.

[0116] Accordingly, the area of ​​the abutment surface 81 can be easily increased compared to a case where the abutment surface 81 is a flat surface other than the inclined surface, and the surface pressure in a case where the abutment surface 81 abuts against the bottom surface 731 of the main valve 64 can be easily suppressed. Therefore, it is easy to suppress the abrasion of the abutment surface 81 and the bottom surface 731 of the main valve 64 against which the abutment surface 81 abuts.

[0117] Moreover, the abrasion powder generated by the contact between the abutment surface 81 and the bottom surface 731 of the main valve 64 is easily guided to the recessed portion 81D provided on the inner side in the radial direction, and thus the abrasion powder is easily discharged through the plurality of abrasion powder discharge holes 81C.

[0118] In the steam valve 14 according to another in Fig. 4A, Fig. 4B and Fig. 4C, the bearing member 80 may have a construction portion 85b constructed with a material different from the material of the main valve 64 and the bearing member 80 at the outer peripheral portion 85, which is the contact portion between the main valve 64 and the bearing member 80.

[0119] Accordingly, it is possible to suppress the abrasion at the outer peripheral portion 85.

[0120] In the steam valve 14 according to another in Fig. 4A, Fig. 4B and Fig. 4C, a linear outer peripheral portion 85a is formed on the outer peripheral portion 85 of the bearing member 80, and a linear inner peripheral portion 733a is formed on the peripheral wall portion 733 of the main valve 64.

[0121] Accordingly, since the linear outer peripheral portion 85a and the linear inner peripheral portion 733a face each other, it is possible to prevent rotation of the bearing member 80 fixed to the main valve 64 and the valve rod 61 about the axis O1, that is, rotation of the main valve 64 about the axis O1 with respect to the valve rod 61.

[0122] The steam valve 14 according to some embodiments includes the throttle valve 43 arranged to face the shutoff valve 45 in the axial direction Z and to abut against the valve seat 48 at a position on the outside in the radial direction with respect to the position of the valve seat 48 against which the main valve 64 abuts. As a result, since the power generation system 1 includes the steam valve 14 capable of suppressing abrasion of the shutoff valve 45, it is possible to reduce the maintenance frequency of the steam valve 14, and thus it is possible to improve the operating efficiency of the power generation system 1.

[0123] A power generation system 1 according to some embodiments includes a steam valve 14 according to some embodiments, a boiler 11 that generates steam, a steam turbine 10 driven by the steam, and a steam supply pipe (first steam supply pipe 12) that connects the boiler 11 and the steam turbine 10 and supplies the steam to the steam turbine 10. The steam valve 14 is provided at the steam supply pipe (first steam supply pipe 12).

[0124] As a result, since the power generation system 1 includes the steam valve 14 capable of suppressing the abrasion of the shut-off valve 45, it is possible to reduce the maintenance frequency of the steam valve 14, and thus it is possible to improve the operating efficiency of the power generation system 1.

[0125] The present disclosure is not limited to the above-described embodiments, and also includes a form in which modifications are added to the above-described embodiments or a form in which the embodiments are appropriately combined with each other.

[0126] For example, contents described in each of the embodiments described above are understood as follows. (1) The steam valve 14 according to at least one embodiment of the present disclosure includes a valve body 41 having a flow path separation portion 47 that separates a steam flow path 52 through which steam flows, and a valve seat 48 provided in a center of the steam flow path 52 and having an opening portion. The steam valve according to at least one embodiment of the present disclosure includes a check valve 45. The check valve 45 has a valve rod 61 that extends in an axial direction Z along which an axis O1 extends and is configured to move back and forth in the axial direction Z. The check valve 45 has a sub-valve 62 that is fixed to a tip end of the valve rod 61 at a tip end portion of the valve rod 61.The shut-off valve 45 includes a main valve 64 including a penetrating portion 71A into which a portion of the tip end portion 61A of the valve rod 61, positioned on a base end side of the valve rod 61 with respect to the tip end, is inserted, which closes the steam flow path 52 by abutting against the valve seat 48, and in which a through hole 71B is formed through which steam flows when the sub-valve 62 is opened. The shut-off valve 45 includes a guide portion 65 movable in the axial direction Z together with the main valve 64 and guides a side surface 62C of the sub-valve 62 to be displaceable along the axial direction Z.

[0127] According to the configuration of (1) described above, the base end side of the main valve 64 is supported by the valve rod 61 so as to be slidable in the penetrating portion 71A, and at the tip end side of the main valve 64, the guide portion 65, which is movable together with the main valve 64, is supported by the sub-valve 62 at the tip end of the valve rod. Accordingly, the distance in the axial direction Z between the position P1 where the main valve is supported on the base end side of the valve rod and the position P2 where the main valve is supported on the tip end side of the valve rod 61 can be relatively large. Therefore, in a state where the shut-off valve 45 is opened, the movement of the swing of the main valve 64 so as to be inclined with respect to the axial direction Z can be easily suppressed.Therefore, it is possible to suppress the abrasion of the shut-off valve 45 in a state where the shut-off valve 45 is opened.

[0128] (2) In some embodiments, in the configuration of (1), the main valve 64 may have a sub-valve seat 71a against which the sub-valve 62 is capable of abutting. The guide portion 65 may guide the side surface 62C of the sub-valve 62 to be displaceable relative to the sub-valve seat 71a at a position on a tip end side of the valve rod 61 along the axial direction Z.

[0129] In the above configuration (2), the position P2 where the main valve 64 is supported on the tip end side of the valve rod 61 can be provided relatively on the tip end side of the valve rod 61. Accordingly, the distance in the axial direction Z between the position P1 where the main valve 64 is supported on the base end side of the valve rod 61 and the position P2 where the main valve 64 is supported on the tip end side of the valve rod 61 can be relatively large.

[0130] (3) In some embodiments, in the configuration of (2), the sub-valve 62 may include a large-diameter portion 623 and a small-diameter portion 625 having a diameter smaller than a diameter of the large-diameter portion 623 and positioned on the tip end side with respect to the large-diameter portion 623. The guide portion 65 may be configured to guide a side surface of the small-diameter portion 625 so as to be slidable along the axial direction Z.

[0131] In the above configuration (3), the position P2 where the main valve 64 is supported on the tip end side of the valve rod 61 can be provided relatively on the tip end side of the valve rod 61. Accordingly, the distance in the axial direction Z between the position P1 where the main valve 64 is supported on the base end side of the valve rod 61 and the position P2 where the main valve 64 is supported on the tip end side of the valve rod 61 can be relatively large.

[0132] (4) In some embodiments, in the configuration of (3), the guide portion 65 may have a facing surface 68 facing the base end side and opposing the large-diameter portion 623. The facing surface 68 may be configured to abut against the large-diameter portion 623 in a case where the sub-valve 62 is opened.

[0133] According to the configuration of (4) described above, since the large-diameter portion 623 abuts against the facing surface 68 and presses the facing surface 68 to move the guide portion 65 and the main valve 64 toward the tip end side, the main valve 64 can be opened. Accordingly, the valve opening mechanism of the main valve 64 can be realized by a relatively simple structure.

[0134] (5) In some embodiments, in the configuration of any one of (1) to (4), the penetrating portion 71A or the valve rod 61 may have a structural portion (structural portion 713a) constructed with a material different from a material of the penetrating portion 71A and the valve rod 61 at a contact portion (contact portion 713) between the penetrating portion 71A and the valve rod 61. The guide portion 65 or the sub-valve 62 may have a structural portion (structural portion 67a or structural portion 66a) constructed with a material different from a material of the guide portion 65 and the sub-valve 62 at a contact portion (inner peripheral surface 67i of through-hole 67h or inner peripheral surface 66i of tubular portion 66) between the guide portion 65 and the sub-valve 62.

[0135] According to the configuration of (5), it is possible to suppress the abrasion of the contact portion (the contact portion 713) between the penetrating portion 71A and the valve rod 61 and the abrasion of the contact portion (the inner peripheral surface 67i of the through hole 67h or the inner peripheral surface 66i of the tubular portion 66) between the guide portion 65 and the sub-valve 62.

[0136] (6) In some embodiments, in the configuration of any one of (1) to (5), a support member 80 positioned closer to the base end side than the main valve 64, fixed to the valve rod 61, and having an abutment surface 81 capable of abutting against a bottom surface 731 facing the base end side of the main valve 64 may be provided. The support member 80 may be configured to support the main valve 64 by having the abutment surface 81 abut against the bottom surface 731 of the main valve 64 in a case where the main valve 64 is opened.

[0137] According to the configuration of (6), the area of ​​the abutment surface 81 can be easily relatively increased. Therefore, it is easy to suppress the surface pressure in a case where the abutment surface 81 abuts against the bottom surface 731 of the main valve 64, and it is easy to suppress the abrasion of the abutment surface 81 and the bottom surface 731 of the main valve 64 against which the abutment surface 81 abuts.

[0138] (7) In some embodiments, in the configuration of (6), an abutment area R of the abutment surface 81 with the bottom surface 731 may include an area located further to an outer side in a radial direction than a position on an outermost side in the radial direction centered on the axis O1 of the sub-valve 62.

[0139] According to the configuration of (7), the area of ​​the abutment surface 81 described above is relatively large. Therefore, it is possible to suppress the surface pressure in a case where the abutment surface 81 abuts against the bottom surface 731 of the main valve 64, and it is possible to suppress the abrasion of the abutment surface 81 and the bottom surface 731 of the main valve 64 against which the abutment surface 81 abuts.

[0140] (8) In some embodiments, in the configuration of (6) or (7), the abutment surface 81 may be an inclined surface inclined toward an inner side in a radial direction centered on the axis O1 toward the base end side.

[0141] According to the configuration of (8), since the area of ​​the abutment surface 81 is slightly increased by making the abutment surface 81 the inclined surface, the surface pressure in a case where the abutment surface 81 abuts against the bottom surface 731 of the main valve 64 is slightly suppressed, and the abrasion of the abutment surface 81 and the bottom surface 731 of the main valve 64 against which the abutment surface 81 abuts is slightly suppressed.

[0142] (9) In some embodiments, in the configuration of any one of (6) to (8), the main valve 64 or the bearing member 80 may have a structural portion (structural portion 85b) constructed with a material different from a material of the main valve 64 and the bearing member 80 at a contact portion (outer peripheral portion 85) between the main valve 64 and the bearing member 80.

[0143] According to the configuration of (9), it is possible to suppress the abrasion at the contact portion (outer peripheral portion 85) between the main valve 64 and the bearing member 80.

[0144] (10) In some embodiments, in the configuration of any one of (6) to (9), the main valve 64 may include an inner peripheral portion (circumferential wall portion 733) configured to be slidable in an outer peripheral portion 85 of the bearing member 80 along the axial direction Z. The bearing member 80 may include a linear outer peripheral portion 85a formed in a linear shape when viewed along the axis O1 in at least a part of the outer peripheral portion 85. The main valve 64 may include a linear inner peripheral portion 733a formed in a linear shape when viewed along the axis O1 in the inner peripheral portion (circumferential wall portion 733) and facing the linear outer peripheral portion 85a.

[0145] According to the configuration of (10), since the linear outer peripheral portion 85a and the linear inner peripheral portion 733a face each other, it is possible to prevent rotation of the bearing member 80 fixed to the main valve 64 and the valve rod 61 around the axis, that is, rotation of the main valve 64 around the axis O1 with respect to the valve rod 61.

[0146] (11) In some embodiments, in the configuration of any one of (1) to (10), a throttle valve 43 may be provided which is arranged to face the shut-off valve 45 and configured to abut against the valve seat 48 at a position located further to an outside in a radial direction centered on the axis O1 than a position of the valve seat 48 against which the main valve 64 abuts, in the axial direction Z.

[0147] According to the configuration of the above (11), since the power generation system 1 includes the steam valve 14 capable of suppressing the abrasion of the shut-off valve 45, it is possible to reduce the maintenance frequency of the steam valve 14, and thus it is possible to improve the operation efficiency of the power generation system 1.

[0148] (12) The power generation system 1 according to at least one embodiment of the present disclosure includes the steam valve 14 having the configuration of any one of (1) to (11), a boiler 11 that generates steam, a steam turbine 10 driven by the steam, and a steam supply pipe (first steam supply pipe 12) that connects the boiler 11 and the steam turbine 10 and supplies the steam to the steam turbine 10. The steam valve 14 is provided at the steam supply pipe (first steam supply pipe 12).

[0149] According to the configuration of the above (12), since the power generation system 1 includes the steam valve 14 capable of suppressing the abrasion of the shut-off valve 45, it is possible to reduce the maintenance frequency of the steam valve 14, and thus it is possible to improve the operation efficiency of the power generation system 1. List of reference symbols 1 energy generation system 10 steam turbine 11 boilers 12 first steam supply pipe 14 Steam valve 41 Valve body 43 throttle valve 45 Shut-off valve 47 Flow path separation section 48 Valve seat 61 Valve rod 62 secondary valve 64 Main valve 65 guide section 68 facing surface 71 Main valve body 71A penetrating section 71B Through hole 80 bearing element 81 contact surface 623 large diameter section 625 small diameter section 713 Contact section 731 floor area QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 2022

[0002] JP 128695

[0002] JP 2014-70513

[0005]

Claims

[1] Steam valve, comprising: a valve body having a flow path separating portion that separates a steam flow path through which steam flows, and a valve seat provided in a center of the steam flow path and having an opening portion; and a shut-off valve, where the shut-off valve contains: a valve rod extending in an axial direction along which an axis extends and configured to move forward and backward in the axial direction, a sub-valve attached to a tip end of the valve rod of a tip end portion of the valve rod, a main valve including a penetrating portion into which a portion of the tip end portion of the valve rod positioned on a base end side of the valve rod with respect to the tip end is inserted, which closes the steam flow path by abutting against the valve seat, and in which a through hole through which steam flows in a case where the sub-valve is opened is formed, and a guide portion movable in the axial direction together with the main valve and guiding a side surface of the sub-valve to be displaceable along the axial direction. [2] Steam valve according to claim 1, wherein the main valve has a secondary valve seat against which the secondary valve is able to rest, and the guide portion guides the side surface of the sub-valve so as to be slidable with respect to the sub-valve seat at a position on a tip end side of the valve rod along the axial direction. [3] Steam valve according to claim 2, wherein the sub-valve has a large-diameter portion and a small-diameter portion having a diameter smaller than a diameter of the large-diameter portion and positioned on the tip end side with respect to the large-diameter portion, and the guide portion guides a side surface of the small diameter portion so that it is displaceable along the axial direction. [4] Steam valve according to claim 3, wherein the guide portion has a facing surface facing the base end side and opposite to the large diameter portion, and the facing surface abuts against the large diameter portion in a case where the sub-valve is open. [5] Steam valve according to one of claims 1 to 4, wherein the penetrating portion or the valve rod has a build-up portion constructed with a material different from a material of the penetrating portion and the valve rod at a contact portion between the penetrating portion and the valve rod, and the guide portion or the sub-valve has a structural portion constructed with a material different from a material of the guide portion and the sub-valve at a contact portion between the guide portion and the sub-valve. [6] Steam valve according to one of claims 1 to 4, further comprising: a bearing element positioned closer than the main valve to the base end side, fixed to the valve rod, and having a bearing surface capable of abutting against a bottom surface facing the base end side of the main valve, wherein the bearing element supports the main valve by having the bearing surface bear against the bottom surface of the main valve in a case where the main valve is open. [7] The steam valve according to claim 6, wherein an abutment portion of the abutment surface with the bottom surface includes a portion located further on an outer side in a radial direction than a position on an outermost side in the radial direction centered on the axis of the sub-valve. [8] The steam valve according to claim 6, wherein the abutment surface is an inclined surface inclined toward an inner side in a radial direction centered on the axis toward the base end side. [9] A steam valve according to claim 6, wherein one of the main valve and the bearing member has a structural portion constructed with a material different from a material of the main valve and the bearing member at a contact portion between the main valve and the bearing member. [10] Steam valve according to claim 6, wherein the main valve has an inner peripheral portion configured to be displaceable in an outer peripheral portion of the bearing member along the axial direction, the bearing element has a linear outer peripheral portion formed in a linear shape when viewed along the axis in at least a part of the outer peripheral portion, and the main valve has a linear inner peripheral portion formed in a linear shape when viewed along the axis in the inner peripheral portion and facing the linear outer peripheral portion. [11] Steam valve according to one of claims 1 to 4, further comprising: a throttle valve arranged to face the shut-off valve and configured to abut against the valve seat at a position located further to an outside in a radial direction centered on the axis than a position of the valve seat against which the main valve abuts, in the axial direction. [12] Power generation system comprising: the steam valve according to one of claims 1 to 4; a boiler that generates steam; a steam turbine driven by the steam; and a steam supply pipe that connects the boiler and the steam turbine and supplies the steam to the steam turbine, whereby the steam valve is provided on the steam supply pipe.

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