Gas-insulated switchgear

Abstract

To solve a problem in which, when the shape of the sides connecting a main pipe and a branch pipe is entirely curved, the planar area of a reinforcing member is small, which tends to reduce the strength of the reinforcing member.SOLUTION: A gas-insulated switchgear includes a pressure vessel (1) including a main pipe (11) and a branch pipe (12), and a plate-shaped reinforcing member (10), the reinforcing member having a first side portion (13), a second side portion (14), and a third side portion (15), the third side portion including a straight portion (151) and a curved portion (152).SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to gas-insulated switchgear. [Background technology]

[0002] Patent Document 1 discloses a gas-insulated switchgear in which a reinforcing rib is provided on the side of a branch pipe as a structure for suppressing stress generated in a vessel formed by a main pipe and a branch pipe branching off from the main pipe. The reinforcing rib described in Patent Document 1 has a curved portion. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2015 / 125307 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the above-described conventional technology, when the shape of the sides connecting the main pipe and the branch pipe is entirely curved, the planar area of ​​the reinforcing member becomes small, which tends to reduce the strength of the reinforcing member. [Means for solving the problem]

[0005] In order to solve the above problems, a gas-insulated switchgear according to one embodiment of the present disclosure comprises a pressure vessel including a main pipe and a branch pipe branching off from the main pipe, and a plate-shaped reinforcing member connected to the main pipe and the branch pipe, the reinforcing member having a first side portion connected to the main pipe, a second side portion connected to the branch pipe, and a third side portion connecting the first side portion and the second side portion, the third side portion including a straight portion and a curved portion concave toward the connection portion between the main pipe and the branch pipe. [Effects of the Invention]

[0006] According to one aspect of the present disclosure, the strength of the reinforcing member can be improved. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a perspective view showing an external configuration of a gas-insulated switchgear according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a partially enlarged view of the gas-insulated switchgear according to the embodiment of the present disclosure. [Figure 3] 10A and 10B are diagrams showing the results of stress analysis using a reinforcing member within the scope of the present disclosure and a reinforcing member outside the scope of the present disclosure. [Figure 4] FIG. 10 is a partially enlarged view of a gas-insulated switchgear according to another embodiment of the present disclosure. [Figure 5] FIG. 10 is a partially enlarged view of a gas-insulated switchgear according to yet another embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0008] [Embodiment 1] FIG. 1 is a perspective view showing the external configuration of a gas-insulated switchgear 101 according to the first embodiment.

[0009] The gas-insulated switchgear 101 mainly comprises a current transformer CT, a cable head CHD, a power receiving unit RU, a second circuit breaker unit 3, a connection unit 4, and a busbar room 5. The power receiving unit RU has a pressure vessel 1 and a first circuit breaker unit 2. The current transformer CT measures the current flowing in the electrical circuit. The cable head CHD is connected to the end of the cable of the electrical circuit.

[0010] The first circuit breaker unit 2, busbar room 5, and second circuit breaker unit 3 are arranged so as to be stacked vertically. Specifically, the second circuit breaker unit 3 is arranged below (directly below) the busbar room 5, and the first circuit breaker unit 2 is arranged above (directly above) the busbar room 5. The connection unit 4 is arranged to the side of the second circuit breaker unit 3. The pressure vessel 1 is arranged above the connection unit 4. The pressure vessel 1 has a main pipe 11 and a branch pipe 12 branching off from the main pipe 11. The branch pipe 12 shown in FIG. 1 is connected to the cable head CHD and has an electrical circuit therein, but is not limited to this, as long as it is a pipe branching off from the pressure vessel 1.

[0011] 2 is a partially enlarged view of the gas-insulated switchgear 101 shown in FIG. 1, and is a schematic diagram showing a state in which the reinforcing member 10 according to the first embodiment is attached to the pressure vessel 1. In other words, the gas-insulated switchgear 101 includes a main pipe 11, a branch pipe 12, and the reinforcing member 10.

[0012] The main pipe 11 is a pipe equipped with a power receiving device inside, and is equipped with a main pipe flange 111 at one end.

[0013] The branch pipe 12 is a pipe branching off from the main pipe 11, and is provided with a branch pipe flange 121 at the end opposite to the end connected to the main pipe 11. In the present disclosure, the branch pipe 12 is connected perpendicularly to the main pipe 11, but this is not necessarily limited to being perpendicular, and the branch pipe 12 may be connected at an angle. The inside of the pressure vessel 1 is filled with an insulating gas, and the inside is maintained at a higher pressure than the outside of the pressure vessel 1.

[0014] When internal pressure is applied to the pressure vessel 1, the main pipe 11 and the branch pipes 12 tend to deform and expand outward, which places a load on the pressure vessel 1. For example, at the connection between the main pipe 11 and the branch pipe 12, a large load is locally placed by the deforming main pipe 11 and branch pipe 12, so a reinforcing member 10 is provided to suppress this deformation.

[0015] The reinforcing member 10 is connected to the main pipe 11 and the branch pipe 12 and reinforces the pressure vessel 1. As shown in the perspective view of FIG. 1, the reinforcing member 10 is plate-shaped. The reinforcing member 10 is formed from a rigid material, such as a metal such as soft iron, aluminum, or stainless steel. As shown in FIG. 2, the planar shape of the reinforcing member 10 includes a first side portion 13, a second side portion 14, and a third side portion 15 connecting the first side portion 13 and the second side portion 14. Hereinafter, the plane refers to a plane that includes the direction in which the first side portion 13 extends and the direction in which the second side portion 14 extends. Hereinafter, the plane that includes the direction in which the first side portion 13 extends and the direction in which the second side portion 14 extends will be simply referred to as a plane. Furthermore, the area of ​​the reinforcing member 10 when viewed from the plane will be simply referred to as the planar area.

[0016] Reinforcing member 10 can be arranged so that first side 13 is located on the side surface of main pipe 11 and second side 14 is located along the side surface of branch pipe. In embodiment 1, because the angle between main pipe 11 and branch pipe 12 is approximately perpendicular, the angle between first side 13 and second side 14 is also approximately perpendicular, but the angle between first side 13 and second side 14 is not limited to being approximately perpendicular. The angle between first side 13 and second side 14 can be changed as appropriate depending on the angle between main pipe 11 and branch pipe 12.

[0017] The first side 13 and the second side 14 are connected to the side of the main pipe 11 and the side of the branch pipe 12, respectively, by welding or the like. The third side 15 refers to the entire line segment connecting the first side 13 and the second side 14. The third side 15 includes a straight portion 151 and a curved portion 152.

[0018] Straight portion 151 is a straight portion of third side 15. Curved portion 152 is a curved portion of third side 15. The curve of curved portion 152 has a shape that is recessed toward the connection portion between main pipe 11 and branch pipe 12.

[0019] Furthermore, straight portion 151 includes first straight portion 151A extending from first side portion 13 substantially perpendicular to main pipe 11, and second straight portion 151B extending from second side portion 14 substantially perpendicular to branch pipe 12. Curved portion 152 is located between first straight portion 151A and second straight portion 151B.

[0020] By including the first linear portion 151A and the second linear portion 151B in the third side portion 15, the planar area of ​​the reinforcing member 10 increases, and therefore the strength of the reinforcing member 10 can be improved.

[0021] Furthermore, at least a portion of the second straight portion 151B is connected to the branch pipe flange 121. The second straight portion 151B and the branch pipe flange 121 may be connected by welding or the like. In the example shown in Fig. 2, the length of the second straight portion 151B is longer than the radial length of the flange surface of the branch pipe flange 121, but it may also be shorter than the radial length of the flange surface.

[0022] By connecting the second straight portion 151B to the branch pipe flange 121, the fixing of the reinforcing member 10 to the pressure vessel 1 becomes even stronger, and the degree of reinforcement of the pressure vessel 1 can be further improved.

[0023] 1, the reinforcing member 10 is attached to a branch pipe 12 having an oval cross section including a straight portion and an arc portion. The reinforcing member 10 is located in the straight portion of the oval cross section of the branch pipe 12.

[0024] When internal pressure is applied to the pressure vessel 1, the side surfaces of the branch pipes 12 corresponding to the straight sections in the cross section tend to deform outward. This deformation causes the side surfaces of the branch pipes 12 corresponding to the arc sections in the cross section to deform inward, placing a large load on the connection between the main pipe 11 and the branch pipes 12. Therefore, in branch pipes 12 with an oval cross section, reducing the possibility of deformation of the side surfaces of the branch pipes 12 corresponding to the straight sections can also reduce the possibility of deformation of the side surfaces of the branch pipes 12 corresponding to the arc sections. As a result, the load on the connection between the main pipe 11 and the branch pipes 12 can be significantly reduced.

[0025] The reinforcing member 10 may also be attached to, for example, an arc portion. Furthermore, the cross-sectional shape of the branch pipe 12 to which the reinforcing member 10 is attached does not necessarily have to be elliptical. For example, the reinforcing member 10 may be attached to a branch pipe 12 whose cross-sectional shape is elliptical or circular.

[0026] A plurality of reinforcing members 10 are arranged for one branch pipe 12. By arranging a plurality of reinforcing members 10, the load applied to the connection between the main pipe 11 and the branch pipe 12 can be further reduced.

[0027] Furthermore, as shown in FIG. 2, the third side portion 15 includes a third straight portion 151C between the curved portion 152 and the second straight portion 151B. The third straight portion 151C is a straight portion extending from the end of the curved portion 152. The curved portion 152 and the third straight portion 151C are connected smoothly enough to be visible. The provision of the third straight portion 151C further increases the planar area of ​​the reinforcing member 10, thereby improving the strength of the reinforcing member 10 itself. The third straight portion 151C may be located between the curved portion 152 and the first straight portion 151A. Alternatively, the third side portion 15 may have the third straight portion 151C both between the curved portion 152 and the second straight portion 151B and between the curved portion 152 and the first straight portion 151A.

[0028] Furthermore, the third side portion 15 may include a chamfered portion 20 as shown in FIG. 2. The chamfered portion 20 is a portion obtained by chamfering a corner included in the third side portion 15. For example, as shown in FIG. 2, the chamfered portion 20 may be provided at a corner between the first straight portion 151A and the curved portion 152. When the third side portion 15 includes a corner, there is a possibility that a worker may be injured depending on the position of the corner. By chamfering the corner, the possibility of the worker being injured can be reduced.

[0029] [Stress analysis] The following describes the results of a stress analysis performed to verify the effect of the reinforcing member 10 having the curved portion 152. Figure 3 shows the results of stress analysis when the reinforcing member 10, which is within the scope of the present disclosure, and the reinforcing member E, which is outside the scope of the present disclosure, are attached to the pressure vessel 1 of embodiment 1. Hereinafter, the verification example when the reinforcing member 10 is attached to the pressure vessel 1 will be referred to as an example, and the verification example when the reinforcing member E is attached to the pressure vessel 1 will be referred to as a comparative example.

[0030] Reinforcing member 10 has the same configuration as described above in embodiment 1, with the third side including curved portion 152. On the other hand, reinforcing member E does not have a third side including curved portion 152; in other words, the third side is composed of only straight lines. Stress distribution diagram 301 shown in Figure 3 is a stress distribution diagram when reinforcing member 10 is attached to pressure vessel 1, and stress distribution diagram 302 is a stress distribution diagram when reinforcing member E is attached to pressure vessel 1. In these two stress distribution diagrams, darker areas indicate lower stress on the material, and lighter areas indicate higher stress.

[0031] To verify the stress generated, a pressure vessel 1 without reinforcing members was first filled with insulating gas at a gauge pressure of 0.7 MPa and a stress analysis was carried out (not shown). In the pressure vessel 1 without reinforcing members, the maximum stress occurred at the connection between the main pipe 11 and the arc section of the branch pipe 12, and the maximum stress at this time was 132 MPa.

[0032] Next, for each of the example and comparative example, an insulating gas was filled into the pressure vessel 1 at a gauge pressure of 0.7 MPa and a stress analysis was performed. The stress at the connection between the main pipe 11 and the arc portion of the branch pipe 12 was 71 MPa in the example and 73 MPa in the comparative example. This confirmed that both reinforcing member 10 and reinforcing member E have the effect of reducing stress at the location where maximum stress occurs in the pressure vessel 1, compared to when no reinforcing member is used.

[0033] Furthermore, the stress generated at the connection between the reinforcing member (10, E) and the main pipe 11 was 132 MPa in the example, while it was 155 MPa in the comparative example. This confirmed that the reinforcing member 10 has the effect of reducing the stress generated at the connection between the reinforcing member (10, E) and the main pipe 11, compared to the reinforcing member E.

[0034] In FIG. 3, a stress distribution diagram 301 of the example shows that a particularly high stress is applied to the curved portion 152 of the reinforcing member 10, as compared with a stress distribution diagram 302 of the comparative example.

[0035] This result demonstrates that the reinforcing member 10, by including the curved portion 152, can alleviate the concentration of stress exerted from the reinforcing member 10 on the main pipe 11. Furthermore, by including the straight portion 151, the reinforcing member 10 can increase the planar area of ​​the reinforcing member 10 compared to a reinforcing member 10 whose third side is only curved, and the strength of the reinforcing member 10 itself can be improved.

[0036] [Embodiment 2] Other embodiments of the present disclosure will be described below. For convenience of explanation, the same reference numerals will be used to designate components having the same functions as those described in the first embodiment, and the description thereof will not be repeated.

[0037] FIG. 4 is a schematic diagram showing a state in which a reinforcing member 10A according to the second embodiment is attached to a pressure vessel 1A.

[0038] 4, the pressure vessel 1A includes a main pipe 11A, a branch pipe 12A, and a reinforcing member 10A. The reinforcing member 10A differs from the reinforcing member 10 of the first embodiment in that the reinforcing member 10A further includes a notch 16 and a notch 17. The other configurations are the same as those of the reinforcing member 10.

[0039] The notch 16 is a notch provided at the corner where the first side 13 and the second side 14 intersect. When the main pipe 11A and the branch pipe 12A are connected by welding, a branch-pipe fillet W3 may be formed at the connection, as shown in FIG. 4 . The notch 16 is cut out to avoid the branch-pipe fillet W3, which prevents the reinforcing member 10A from being connected near the branch-pipe fillet W3. For example, if an additional weld is provided near the branch-pipe fillet W3 formed by welding, there is a concern that the strength may be reduced due to thermal effects. Therefore, when the main pipe 11A and the branch pipe 12A are connected by welding and the reinforcing member 10A and the pressure vessel 1A are connected by welding, the provision of the notch 16 allows the reinforcing member 10A to be connected without interfering with the branch-pipe fillet W3.

[0040] The notch 17 is a notch provided at the corner where the second side portion 14 and the second straight portion 151B intersect. When the branch pipe 12A and the branch pipe flange 121 are connected by welding, a branch pipe flange fillet W2 may be formed at the connection, as in the branch pipe 12A shown in FIG. 4 . The notch 17 is cut out to avoid the branch pipe flange fillet W2, which prevents the reinforcing member 10A from being connected near the branch pipe flange fillet W2. As mentioned above, if additional welds are provided near the welded portions, there is a concern that the strength may be reduced due to thermal effects. Therefore, when the branch pipe flange 121 and the branch pipe 12A are connected by welding and the reinforcing member 10A and the pressure vessel 1A are connected by welding, the provision of the notch 17 allows the reinforcing member 10A to be connected without interfering with the branch pipe flange fillet W2.

[0041] [Embodiment 3] Further embodiments of the present disclosure will be described below. For convenience of explanation, the same reference numerals will be used to designate components having the same functions as those described in the first and second embodiments, and the description thereof will not be repeated.

[0042] FIG. 5 is a schematic diagram showing a state in which a reinforcing member 10B according to the third embodiment is attached to a pressure vessel 1B.

[0043] As shown in FIG. 5, pressure vessel 1B includes main pipe 11A, branch pipe 12A, and reinforcing member 10B. Reinforcing member 10B includes third side portion 15A instead of third side portion 15 of reinforcing member 10A of embodiment 2. Reinforcing member 10B also includes notch portion 18 and notch portion 19, and differs from reinforcing member 10A of embodiment 2 in that it does not include notch portion 17. However, for the sake of convenience of explanation, notch portion 17 is omitted, and in reality, notch portion 17 may be included as necessary. The rest of the configuration is similar to that of reinforcing member 10A.

[0044] The third side portion 15A has a straight line portion 1511 and a curved line portion 1522. The straight line portion 1511 includes a first straight line portion 151A, a second straight line portion 151B, a third straight line portion 151C, and a fourth straight line portion 151D. The third straight line portion 151C and the fourth straight line portion 151D are straight line portions located between the first straight line portion 151A and the second straight line portion 151B.

[0045] The curved portion 1522 includes a first curved portion 152A and a second curved portion 152B. The first curved portion 152A is located between the third straight portion 151C and the fourth straight portion 151D. The second curved portion 152B is located between the fourth straight portion 151D and the second straight portion 151B. In other words, the third side portion 15A is connected in this order to the first straight portion 151A, the third straight portion 151C, the first curved portion 152A, the fourth straight portion 151D, the second curved portion 152B, and the second straight portion 151B.

[0046] According to the above configuration, two curved portions 1522 are provided, and a straight portion 151 is interposed between the two curved portions 1522, which makes it possible to further increase the planar area of ​​the reinforcing member 10B, and further improve the strength of the reinforcing member 10B itself.

[0047] The position of each straight line portion of straight line portion 1511 and the position of each curved line portion of curved line portion 1522 may be arranged arbitrarily, and the number of straight line portions of straight line portion 1511 and the number of curved line portions of curved line portion 1522 may also be set arbitrarily.

[0048] Furthermore, third side portion 15A may have one or more curved portions, and for example, third side portion 15A may have only second curved portion 152B as the curved portion, and the portion corresponding to first curved portion 152A may not have a curved portion. In other words, third straight portion 151C and fourth straight portion 151D may be continuous.

[0049] 5, at least a portion of the first straight portion 151A of the reinforcing member 10B is connected to the main pipe flange 111. By connecting the first straight portion 151A to the main pipe flange 111, the reinforcing member 10B is further fixed, and the reinforcement of the pressure vessel 1B is further strengthened.

[0050] The notch 18 is provided at the corner where the first side portion 13 and the first linear portion 151A intersect. When the main pipe 11A and the main pipe flange 111 are connected by welding, a main pipe flange fillet W1 may be formed at the connection, as shown in FIG. 5 . The notch 18 is cut out to avoid the main pipe flange fillet W1, which prevents the reinforcing member 10B from being connected near the main pipe flange fillet W1. As mentioned above, if additional welds are provided near the welded portions, there is a concern that the strength may be reduced due to thermal effects. Therefore, when the main pipe flange 111 and the main pipe 11 are connected by welding and the reinforcing member 10B and the pressure vessel 1B are connected by welding, the provision of the notch 18 allows the reinforcing member 10B to be connected without interfering with the main pipe flange fillet W1.

[0051] Furthermore, the notches 19 are provided in the first side portion 13 at locations other than the corners near the connection between the main pipe flange 111 and the main pipe 11. Providing the notches 19 in the first side portion 13 eliminates the need to weld the entire first side portion 13, reducing the number of welding locations and improving work efficiency.

[0052] 〔summary〕 A first aspect of the gas-insulated switchgear according to the present disclosure comprises a pressure vessel including a main pipe and a branch pipe branching off from the main pipe, and a plate-shaped reinforcing member connected to the main pipe and the branch pipe, the reinforcing member having a first side portion connected to the main pipe, a second side portion connected to the branch pipe, and a third side portion connecting the first side portion and the second side portion, the third side portion including a straight portion and a curved portion concave toward the connection portion between the main pipe and the branch pipe.

[0053] Aspect 2 of the gas-insulated switchgear according to the present disclosure is aspect 1, wherein the straight portion includes a first straight portion extending from the first side portion approximately perpendicular to the main pipe and a second straight portion extending from the second side portion approximately perpendicular to the branch pipe, and the curved portion is located between the first straight portion and the second straight portion.

[0054] A third aspect of the gas-insulated switchgear according to the present disclosure is the same as that of the first or second aspect, in which the third side portion includes a third straight portion between the curved portion and the first straight portion, or between the curved portion and the second straight portion.

[0055] A fourth aspect of the gas-insulated switchgear according to the present disclosure is any one of the first to third aspects, wherein the branch pipe has a branch pipe flange at an end opposite to the connection with the main pipe, and at least a portion of the second straight portion is connected to the branch pipe flange.

[0056] A fifth aspect of the gas-insulated switchgear according to the present disclosure is any one of the first to fourth aspects, wherein an end of the main pipe is provided with a main pipe flange, and at least a portion of the first straight portion is connected to the main pipe flange.

[0057] A sixth aspect of the gas-insulated switchgear according to the present disclosure is any one of the first to fifth aspects, wherein the cross-sectional shape of the branch pipe is an elliptical shape including a straight portion and an arc portion, and the reinforcing member is located in the straight portion.

[0058] A seventh aspect of the gas-insulated switchgear according to the present disclosure is any one of the first to sixth aspects, wherein the reinforcing member has a notch at a corner where the first side portion and the second side portion intersect.

[0059] An eighth aspect of the gas-insulated switchgear according to the present disclosure is any one of the first to seventh aspects, wherein the reinforcing member has a notch at a corner where the second side portion and the second linear portion intersect.

[0060] A ninth aspect of the gas-insulated switchgear according to the present disclosure is any one of the first to eighth aspects, wherein the reinforcing member has a notch at a corner where the first side portion and the first linear portion intersect.

[0061] A tenth aspect of the gas-insulated switchgear according to the present disclosure is any one of the first to ninth aspects, wherein the reinforcing member further has notches in the first side portion at locations other than the corners.

[0062] The present disclosure is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present disclosure. [Explanation of symbols]

[0063] 101 Gas-insulated switchgear 1, 1A, 1B Pressure Vessel 10, 10A, 10B Reinforcement members 11 Main manager 111 Main pipe flange 12, 12A branch pipe 121 Branch pipe flange 13 First side 14 Second side 15, 15A Third side 151, 1511 Straight section 151A 1st straight section 151B 2nd straight section 151C 3rd straight section 152, 1522 curved section 16, 17, 18, 19 Notches

Claims

1. a pressure vessel including a main pipe and a branch pipe branching from the main pipe; a plate-shaped reinforcing member connected to the main pipe and the branch pipe; The reinforcing member is a first side portion connected to the main pipe; a second side portion connected to the branch pipe; a third side portion connecting the first side portion and the second side portion, the third side portion includes a straight portion and a curved portion recessed toward a connection portion between the main pipe and the branch pipe.

2. 2. The gas-insulated switchgear according to claim 1, wherein the straight portion includes a first straight portion extending from the first side portion substantially perpendicular to the main pipe and a second straight portion extending from the second side portion substantially perpendicular to the branch pipe, and the curved portion is located between the first straight portion and the second straight portion.

3. 3. The gas-insulated switchgear according to claim 2, wherein the third side portion includes a third straight portion between the curved portion and the first straight portion or between the curved portion and the second straight portion.

4. the branch pipe has a branch pipe flange at an end opposite to the connection portion with the main pipe, The gas-insulated switchgear according to claim 2 , wherein at least a portion of the second straight portion is connected to the branch pipe flange.

5. an end of the main pipe having a main pipe flange; The gas-insulated switchgear according to claim 2 , wherein at least a portion of the first straight portion is connected to the main pipe flange.

6. The cross-sectional shape of the branch pipe is an ellipse including a straight portion and an arc portion, The gas-insulated switchgear according to claim 1 , wherein the reinforcing member is located in the straight portion.

7. The gas-insulated switchgear according to claim 1 , wherein the reinforcing member has a notch at a corner where the first side portion and the second side portion intersect.

8. The gas-insulated switchgear according to claim 4 , wherein the reinforcing member has a notch at a corner where the second side portion and the second linear portion intersect.

9. The gas-insulated switchgear according to claim 5 , wherein the reinforcing member has a notch at a corner where the first side portion and the first linear portion intersect.

10. The gas-insulated switchgear according to claim 9 , wherein the reinforcing member further has notches at locations other than the corners on the first side.

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