Valve body insertion / removal device, valve body insertion method, and valve body removal method

Abstract

To provide a valve body insertion / removal device which achieves high workability, and to provide a valve body insertion method and a valve body removal method.SOLUTION: A valve body insertion / removal device 10 inserts / removes a valve body V into / from a boring part of a fluid pipe in a state that flow of a fluid is not interrupted. The valve body insertion / removal device 10 includes: a shaft part 2 which may move forward or rearward along an insertion / removal direction X of the valve body V; a first jig 3 having a first flange part 31 connected to a lower end of the shaft part 2, and a first cylindrical part 32 extending downward from a lower surface 31b of the first flange part 31; a second jig 4 having a second flange part 41 connected to an upper end of the valve body V, and a second cylindrical part 42 which extends upward from an upper surface 41a of the second flange part 41 and may fit in the first cylindrical part 32; and a rod-like connection member 5 which connects the first jig 3 with the second jig 4 in a state that the first cylindrical part 32 and the second cylindrical part 42 are fitted.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a valve body inserting / extracting device, a valve body inserting method, and a valve body removing method. [Background technology]

[0002] BACKGROUND ART Conventionally, a valve body inserting / removing device, a valve body inserting method, and a valve body removing method for inserting / removing a valve body into / from a perforated portion of a fluid pipe under an uninterrupted flow condition are known (see, for example, Patent Document 1).

[0003] Patent Document 1 describes a valve body insertion / extraction device in which the shaft (insertion rod) of an insertion machine is connected to a valve body. When using this valve body insertion / extraction device to insert a valve body into a perforated portion of a fluid pipe, a housing that hermetically surrounds the fluid pipe and a work case that is connected to the housing via a work valve and can hermetically house the valve body insertion / extraction device are arranged, and then the valve body insertion / extraction device is housed in the work case, and the valve body is inserted using the valve body insertion / extraction device. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-250295 Summary of the Invention [Problem to be solved by the invention]

[0005] The work case housing the valve body and the valve body insertion / extraction device is large in volume and has a long vertical dimension because the valve body can be moved vertically. When the interior of such a work case is filled with fluid and sealed, the work case can expand vertically due to pressure from the fluid. Therefore, when the fluid in the work case is drained to reduce the internal pressure, the force acting on the work case is transmitted to the valve body via the shaft, causing stress at the connection between the shaft and the valve body. This creates a problem when the valve body and the shaft of the valve body insertion / extraction device are connected by, for example, a bolt, making it difficult to remove the bolt and separate the valve body from the valve body insertion / extraction device. Furthermore, stress acts on the motor connected to the shaft via the shaft, potentially subjecting the motor to excessive force and causing it to malfunction.

[0006] Therefore, there is a need for a valve disc insertion / removal device, valve disc insertion method, and valve disc removal method that are easy to use even when inserting or removing a valve disc into a perforated portion of a fluid pipe under uninterrupted flow conditions. [Means for solving the problem]

[0007] The characteristic configuration of the valve body insertion / removal device of the present invention is a valve body insertion / removal device that inserts and removes a valve body into a perforated portion of a fluid pipe under an uninterrupted flow condition, and is equipped with a first jig having an axial portion that can advance and retreat along the insertion / removal direction of the valve body, a first flange portion connected to the lower end of the axial portion, and a first cylindrical portion extending downward from the lower surface of the first flange portion, a second jig having a second flange portion connected to the upper end of the valve body and a second cylindrical portion that extends upward from the upper surface of the second flange portion and can be fitted with the first cylindrical portion, and a rod-shaped connecting member that connects the first jig and the second jig when the first cylindrical portion and the second cylindrical portion are fitted together.

[0008] According to this configuration, the first jig and the second jig are disposed between the shaft portion and the valve body, so that the shaft portion and the valve body are not directly connected. The first jig and the second jig each have a first flange portion or a second flange portion, and a first tubular portion or a second tubular portion, which connect to the shaft portion or the valve body, respectively. The first tubular portion and the second tubular portion are fitted together and connected. Because the shaft portion and the valve body are connected via the first jig and the second jig, for example, by changing the relative positions of the first jig and the second jig, a stress absorption margin can be provided to absorb stress acting from the shaft portion to the first jig when the working case is depressurized. That is, when the valve body is inserted, the lower surface of the first flange portion and / or the lower surface of the first tubular portion abuts against the second jig to facilitate the application of force from the shaft portion to the valve body. After the valve body is inserted, the relative positions are changed so that the lower surfaces of the first flange portion and the first tubular portion do not abut against the second jig. As a result, even if stress acts from the shaft portion to the first jig when the working case is depressurized, the underside of the first flange portion or the underside of the first tubular portion can be separated from the second jig by an amount equal to the absorption allowance, allowing the stress to be absorbed by the absorption allowance. Therefore, even if the valve disc is inserted into the perforated portion of the fluid pipe under uninterrupted flow conditions, stress is prevented from acting on the valve disc from the valve disc insertion / extraction device when the working case is depressurized. This makes it easy to separate the valve disc from the valve disc insertion / extraction device, improving the workability of the valve disc insertion operation. It also reduces problems such as damage to the connection between the shaft portion and the valve disc and motor failure.

[0009] Another characteristic feature is that the first tubular portion and the second tubular portion have insertion holes formed therein through which the connecting member is inserted, and the insertion hole in either the first tubular portion or the second tubular portion is an elongated hole whose dimension in the insertion / removal direction is larger than the diameter of the connecting member.

[0010] According to this configuration, the dimension of the insertion hole of either the first cylindrical portion or the second cylindrical portion in the insertion / removal direction is larger than the diameter of the connecting member, so the first jig can be moved in the vertical direction even with the connecting member inserted in the insertion hole. This makes it possible to change the positional relationship between the first jig and the second jig and provide an absorption allowance without removing the connecting member, thereby improving the workability of the valve body insertion operation.

[0011] Another characteristic feature is that the second flange portion has a through hole through which a valve body-related member arranged at the upper end of the valve body is inserted, and the insertion hole is formed in a position that can avoid interference between the connecting member and the valve body-related member.

[0012] According to this configuration, even if a valve-body-related member such as a valve stem or a reducer is arranged at the upper end of the valve body, the second flange portion can be connected to the upper end of the valve body, and interference between the connecting member inserted into the insertion hole and the valve-body-related member can be avoided, making it possible to connect the valve body having the valve-body-related member to the first jig and the second jig.

[0013] Another characteristic feature is that the first cylindrical portion and the second cylindrical portion have at least two or more insertion holes through which at least two or more connecting members are inserted, and the at least two or more insertion holes are formed at positions sandwiching the valve body-related member.

[0014] This configuration makes it possible to avoid interference between the valve-related member and the connecting member without increasing the extension dimensions of the first and second cylindrical portions, thereby suppressing an increase in the valve insertion stroke of the shaft portion and making the valve insertion / extraction device more compact.

[0015] Another characteristic feature is that when the valve body is inserted, either the lower surface of the first flange portion or the lower surface of the first cylindrical portion abuts against the second jig.

[0016] According to this configuration, either the lower surface of the first flange portion or the lower surface of the first cylindrical portion abuts against the second jig, so that either the upper surface of the second cylindrical portion or the upper surface of the second flange portion and the first jig are always spaced apart, which makes it easy to adjust the positional relationship between the first jig and the second jig.

[0017] In addition, a characteristic configuration of a valve body insertion method using a valve body insertion / extraction device according to one embodiment of the present invention is that it includes the steps of: arranging a housing that surrounds the fluid pipe in a sealed state; and a work case that is connected to the housing via a work valve and can house the valve body insertion / extraction device in a sealed state; engaging the first cylindrical portion with the second cylindrical portion, connecting the first jig with the second jig using the connecting member, and accommodating the valve body insertion / extraction device in the work case; sealing the work case and inserting the valve body into the perforated portion of the fluid pipe with either the underside of the first flange portion or the underside of the first cylindrical portion abutting against the second jig; and after inserting the valve body, discharging the fluid in the work case with the underside of the first flange portion and the underside of the first cylindrical portion separated from the second jig, and removing the valve body insertion / extraction device from the work case.

[0018] According to this configuration, by abutting either the underside of the first flange or the underside of the first tubular portion with the second jig, the valve can be inserted into the bore of the fluid pipe while the force of the shank is applied to the valve via the first and second jigs. Furthermore, by discharging the fluid from the working case while separating the undersides of the first flange and the first tubular portion from the second jig, stress acting on the shank when the working case is depressurized can be absorbed by the absorption pad. This prevents stress from acting on the valve from the shank when the working case is depressurized, even when the valve is inserted into the bore of the fluid pipe under uninterrupted flow conditions. This allows for easy separation of the valve from the valve insertion / extraction device, improving the workability of the valve insertion operation. It also reduces problems such as damage to the connection between the shank and the valve and motor failure.

[0019] Another characteristic feature is that the step of removing the valve body inserting / extracting device from the work case is performed by removing the connecting member.

[0020] The fluid in the working case is discharged with the underside of the first flange and the underside of the first cylindrical portion separated from the second jig, so no stress acts on the shaft. Therefore, with this configuration, the connection between the shaft and the first and second jigs can be easily released by removing the connecting member connecting the first and second jigs. Furthermore, by releasing the connection between the second jig and the valve body, the valve body insertion / extraction device can be easily removed.

[0021] Another characteristic feature is that the housing has a plurality of drain ports for discharging or inflowing fluid, and the process of inserting the valve body into the perforated portion is carried out in a state where the drain ports provided upstream of the insertion position of the valve body are connected to the drain ports provided downstream of the insertion position.

[0022] When inserting a valve disc into a perforated portion of a fluid pipe under uninterrupted flow conditions, fluid pressure acts on the upstream surface of the valve disc. According to this configuration, the housing has multiple drain ports for discharging or introducing fluid, and the valve disc insertion step is performed while the drain ports located upstream of the valve disc insertion position are in communication with the drain ports located downstream of the insertion position, thereby reducing the fluid pressure acting on the upstream surface of the valve disc. This allows the valve disc insertion step to be performed efficiently.

[0023] In addition, a valve body insertion / extraction device according to one embodiment of the present invention further includes a third jig having a third flange portion connected to the lower end of the shaft portion, and a third cylindrical portion extending downward from the underside of the third flange portion and capable of engaging with the second cylindrical portion, wherein the distance between the second cylindrical portion and the third cylindrical portion in a plane perpendicular to the insertion / extraction direction when the second cylindrical portion and the third cylindrical portion are engaged with each other is greater than the distance between the first cylindrical portion and the second cylindrical portion in the plane when the first cylindrical portion and the second cylindrical portion are engaged with each other. The characteristic configuration of the valve body removal method using the valve body insertion / removal device is that it includes the steps of: arranging a housing that surrounds the fluid pipe in a sealed state; and a work case that is connected to the housing via a work valve and can house the valve body insertion / removal device in a sealed state; connecting the second jig and the third jig connected to the upper end of the valve body with the connecting member, and connecting the third jig to the shaft portion; and sealing the work case and removing the valve body from the perforated portion of the fluid pipe.

[0024] According to this configuration, the third jig has a third flange portion connected to the lower end of the shank portion and a third tubular portion that can be fitted with the second tubular portion, and the separation distance between the second tubular portion and the third tubular portion in a plane perpendicular to the insertion / removal direction when the second tubular portion and the third tubular portion are fitted together is greater than the separation distance between the first tubular portion and the second tubular portion in a plane perpendicular to the insertion / removal direction when the first tubular portion and the second tubular portion are fitted together, so the third jig is easier to fit with the second jig than the first jig. Therefore, when connecting the second jig and the third jig with the connecting member, it is not necessary to precisely align the central axis of the shank portion and the central axis of the second tubular portion, thereby improving the workability of the connection operation. [Brief explanation of the drawings]

[0025] [Figure 1] FIG. [Figure 2] FIG. 4 is a vertical cross-sectional view of a first jig and a second jig. [Figure 3] FIG. 4 is a vertical cross-sectional view of a second jig and a third jig. [Figure 4]FIG. 1 is a front (or side) view of a housing and a work case connected to a fluid pipe. [Figure 5] FIG. 10 is a cross-sectional view of a drilling device installed in a work case. [Figure 6] FIG. 10 is a cross-sectional view of a valve body insertion / extraction device installed in a work case. [Figure 7] FIG. 10 is a cross-sectional view of a valve body insertion / extraction device installed in a work case. [Figure 8] FIG. 10 is a cross-sectional view of a valve body insertion / extraction device installed in a work case. [Figure 9] FIG. 10 is a cross-sectional view of a valve body insertion / extraction device installed in a work case. [Figure 10] FIG. 10 is a plan view showing a case in which branch pipes are installed according to another embodiment. [Figure 11] FIG. 10 is a front (or side) view of a housing connected to a fluid pipe according to another embodiment. [Figure 12] FIG. 10 is a longitudinal cross-sectional view of a first jig and a second jig connected to a valve body according to another embodiment. [Figure 13] FIG. 10 is a longitudinal cross-sectional view of a first jig and a second jig connected to a valve body according to another embodiment. [Figure 14] FIG. 14 is a cross-sectional view of a first jig and a second jig connected to a valve body, taken along the line XIV-XIV, according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0026] Hereinafter, an embodiment of the valve body insertion / extraction device according to the present invention will be described with reference to the drawings. However, the present invention is not limited to the following embodiment, and various modifications are possible without departing from the spirit and scope of the present invention.

[0027] [Valve body insertion / extraction device] 1 to 3, a valve disc insertion / extraction device 10 according to this embodiment will be described. The valve disc insertion / extraction device 10 is a device for inserting a valve disc V into a bore hole in a fluid pipe W or for removing the valve disc V from the fluid pipe W. As shown in FIG. 1, the valve disc insertion / extraction device 10 comprises a shaft 2, a first jig 3, a second jig 4, and a connecting member 5. Hereinafter, the up and down directions will be defined according to the position of the valve disc insertion / extraction device 10 in FIG. 1, and the direction in which the valve disc insertion / extraction device 10 inserts the valve disc V into the bore hole in the fluid pipe W may be referred to as "downward," and the direction in which the valve disc insertion / extraction device 10 removes the valve disc V from the bore hole may be referred to as "upward." The insertion / removal direction is defined as X, and a plane perpendicular to the insertion / removal direction X is defined as a horizontal plane.

[0028] The valve body insertion / extraction device 10 has a connection part 1 that can be connected in a sealed state to the upper opening of a work case 9, which will be described later. The shaft part 2 passes through the connection part 1 and is a member that can move back and forth in the insertion / extraction direction X of the valve body V along the axis O. The upper end of the shaft part 2, which is located above the connection part 1, is connected to a motor (not shown) that drives the shaft part 2, and a flange part 21 is formed at the lower end of the shaft part 2, which is located below the connection part 1.

[0029] The first jig 3 is a jig that is connected to the shaft portion 2 when inserting the valve body V, and as shown in FIGS. 1 and 2 , has a first flange portion 31 and a first cylindrical portion 32 that extends downward from a lower surface 31b of the first flange portion 31. The first flange portion 31 has substantially the same shape as the flange portion 21, and the upper surface 31a of the first flange portion 31 and the lower surface 21b of the flange portion 21 are fastened together with fastening members 22 while in contact with each other, thereby connecting the shaft portion 2 and the first jig 3. The flange portion 21 and the first flange portion 31 may each be provided with holes 24, 34 into which fastening members 22 such as bolts can be inserted. The first jig 3 is preferably connected to the shaft portion 2 so that its central axis coincides with the axis center O. The shape of the first flange portion 31 may be different from the shape of the flange portion 21.

[0030] The outer diameter L1 of the first cylindrical portion 32 is smaller than the radial dimension of the first flange portion 31. Furthermore, the central axis of the first cylindrical portion 32 and the central axis of the first flange portion 31 are substantially aligned, and therefore the central axis of the first cylindrical portion 32 is substantially aligned with the axis O. Note that although the first cylindrical portion 32 in this embodiment has a cylindrical shape, it may also have a rectangular cylindrical shape. Furthermore, the first cylindrical portion 32 does not have to be cylindrical, and may also have a cylindrical or polygonal prism shape.

[0031] A first insertion hole 33 (an example of an insertion hole) through which a connecting member 5 (described later) can be inserted is provided on a side surface of the first cylindrical portion 32. Since the connecting member 5 is inserted so as to penetrate the first cylindrical portion 32, the first insertion hole 33 is provided on both side surfaces of the first cylindrical portion 32 that face each other across the central axis of the first cylindrical portion 32. That is, the first cylindrical portion 32 has two first insertion holes 33 on its side surface. As shown in FIG. 2 , the first insertion hole 33 in this embodiment is formed as an elongated hole whose dimension h1 in the insertion / removal direction X is larger than its dimension in the horizontal direction. The dimension h1 of the first insertion hole 33 in the insertion / removal direction X is preferably larger than the dimension h0 of the connecting member 5 in the radial direction, and the dimension of the first insertion hole 33 in the horizontal direction is preferably approximately the same as the dimension h0 of the connecting member 5. As a result, the connecting member 5 inserted into the first insertion hole 33 can move along the insertion / removal direction X by the difference between the dimension h1 and the dimension h0 while its movement in the horizontal direction is restricted. When the first cylindrical portion 32 is a columnar body, the first insertion hole 33 may be provided as a through-hole penetrating the columnar body. The shape of the long hole may be elliptical or rectangular.

[0032] 1 and 2, the second jig 4 has a second flange portion 41 connected to the upper end of the valve disc V, and a second cylindrical portion 42 extending upward from an upper surface 41a of the second flange portion 41. The second jig 4 is connected to the valve disc V by fastening the lower surface 41b of the second flange portion 41 to an upper surface Va of the valve disc V with fastening members 45 in a state where the lower surface 41b of the second flange portion 41 and the upper surface Va of the valve disc V are in contact with each other. The second flange portion 41 and the valve disc V may be provided with holes 44, Vb into which the fastening members 45, such as bolts, can be inserted. The second jig 4 may be connected to the valve disc V so that its central axis coincides with the central axis of the valve disc V.

[0033] The inner diameter L2 of the second cylindrical portion 42 is smaller than the radial dimension of the second flange portion 41. Furthermore, the central axis of the second cylindrical portion 42 and the central axis of the second flange portion 41 are substantially aligned, and therefore the central axis of the second cylindrical portion 42 is substantially aligned with the central axis of the valve body V. Although the second cylindrical portion 42 in this embodiment has a cylindrical shape, it may also have a rectangular cylindrical shape.

[0034] As shown in FIG. 2 , the inner diameter L2 of the second cylindrical portion 42 is preferably slightly larger than the outer diameter L1 of the first cylindrical portion 32. This allows the first cylindrical portion 32 to be fitted into the internal space of the second cylindrical portion 42. To accurately insert the valve body V, the axis O and the central axis of the valve body V must be approximately aligned. Therefore, the inner diameter L2 is preferably determined so that the inner circumferential surface of the second cylindrical portion 42 abuts against the outer circumferential surface of the first cylindrical portion 32, thereby restricting radial movement of the first cylindrical portion 32 relative to the second cylindrical portion 42. Therefore, the inner diameter L2 of the second cylindrical portion 42 is preferably approximately the same as the outer diameter L1 of the first cylindrical portion 32.

[0035] A dimension H2 of the second cylindrical portion 42 in the insertion / removal direction X may be smaller than a dimension H1 of the first cylindrical portion 32 in the insertion / removal direction X. Accordingly, when the first cylindrical portion 32 and the second cylindrical portion 42 are fitted together and the lower surface 32b of the first cylindrical portion 32 abuts against the upper surface 41a of the second flange portion 41, the lower surface 31b of the first flange portion 31 and the upper surface 42a of the second cylindrical portion 42 are spaced apart by the difference between the dimensions H1 and H2. As a result, when the first cylindrical portion 32 and the second cylindrical portion 42 are fitted together, the surface area where the first jig 3 and the second jig 4 abut can be reduced.

[0036] The side surface of the second cylindrical portion 42 is provided with a second insertion hole 43 through which the connecting member 5 (described later) can be inserted. Since the connecting member 5 is inserted so as to penetrate the second cylindrical portion 42, the second insertion holes 43 are provided on both side surfaces of the second cylindrical portion 42 that face each other across the central axis of the second cylindrical portion 42. That is, the second cylindrical portion 42 has two second insertion holes 43 on its side surface. As shown in FIGS. 1 and 2 , the second insertion hole 43 in this embodiment has a circular shape that is substantially the same as the cross-sectional shape of the connecting member 5. Therefore, the radial dimension h2 of the second insertion hole 43 is substantially the same as the radial dimension h0 of the connecting member 5 and is smaller than the dimension h1 of the first insertion hole 33 in the insertion / removal direction X.

[0037] The upper end of the second insertion hole 43 is located below the upper end of the first insertion hole 33 when the first cylindrical portion 32 and the second cylindrical portion 42 are fitted together and the lower surface 32b of the first cylindrical portion 32 abuts against the upper surface 41a of the second flange portion 41 (see FIG. 7). This allows the connecting member 5 to be inserted through the first insertion hole 33 and the second insertion hole 43 with the lower surface 32b of the first cylindrical portion 32 abutting against the upper surface 41a of the second flange portion 41.

[0038] Furthermore, the dimension ha from the center of the first insertion hole 33 to the lower surface 32b of the first tubular portion 32 in the insertion / removal direction X is set to be smaller than the dimension hb from the center of the second insertion hole 43 to the upper surface 41a of the second flange portion 41. Therefore, when the lower surface 32b of the first tubular portion 32 abuts against the upper surface 41a of the second flange portion 41, the center of the first insertion hole 33 in the insertion / removal direction X is located lower than the center of the second insertion hole 43 in the insertion / removal direction X (see FIG. 7 ). Therefore, the distance between the lower end of the connecting member 5 inserted into the first insertion hole 33 and the lower edge of the first insertion hole 33 is larger than the distance between the upper end of the connecting member 5 and the upper edge of the first insertion hole 33, making it easier to move the first jig 3 upward in a state where the first jig 3 and the second jig 4 are connected by the connecting member 5.

[0039] The connecting member 5 is a rod-shaped member that connects the first jig 3 and the second jig 4, and is inserted into the first insertion hole 33 and the second insertion hole 43. The axial length of the connecting member 5 is preferably greater than the inner diameter L2 of the second cylindrical portion 42. The connecting member 5 is preferably composed of, for example, a bolt and a nut. The first jig 3 and the second jig 4 are preferably connected by the connecting member 5 in a state in which radial movement of the first cylindrical portion 32 and the second cylindrical portion 42 is restricted (see FIGS. 6 to 8).

[0040] Next, the third jig 6 included in the valve disc insertion / extraction device 10 will be described with reference to FIG. 3 . The third jig 6 is a jig that is connected to the shaft portion 2 when removing the valve disc V, and has a third flange portion 61 and a third tubular portion 62 that extends downward from a lower surface 61 b ​​of the third flange portion 61. The third flange portion 61 has substantially the same shape as the flange portion 21, and is connected to the shaft portion 2 by fastening the upper surface 61 a of the third flange portion 61 to the lower surface 21 b of the flange portion 21 with the fastening members 22 in abutting relationship. The third flange portion 61 may be provided with a hole 64 into which the fastening member 22, such as a bolt, can be inserted. The third jig 6 is preferably connected to the shaft portion 2 so that its central axis coincides with the axis O. The shape of the third flange portion 61 may be different from the shape of the flange portion 21.

[0041] The outer diameter L3 of the third cylindrical portion 62 is smaller than the radial dimension of the third flange portion 61 and smaller than the outer diameter L1 of the first cylindrical portion 32. The outer diameter L3 of the third cylindrical portion 62 is also smaller than the inner diameter L2 of the second cylindrical portion 42. That is, when the second cylindrical portion 42 and the third cylindrical portion 62 are fitted together, the horizontal distance between the inner circumferential surface of the second cylindrical portion 42 and the outer surface of the third cylindrical portion 62 is greater than the horizontal distance between the outer surface of the first cylindrical portion 32 and the inner circumferential surface of the second cylindrical portion 42 when the first cylindrical portion 32 and the second cylindrical portion 42 are fitted together. This makes it easier for the second cylindrical portion 42 and the third cylindrical portion 62 to fit together, thereby improving the efficiency of the connection work between the second jig 4 and the third jig 6.

[0042] Furthermore, since the central axis of the third cylindrical portion 62 and the central axis of the third flange portion 61 are substantially aligned, the central axis of the third cylindrical portion 62 is substantially aligned with the axis center O. Note that although the first cylindrical portion 32 in this embodiment has a cylindrical shape, it may also have a rectangular cylindrical shape. Furthermore, the third cylindrical portion 62 does not have to be cylindrical, and may also have a cylindrical or polygonal prism shape.

[0043] The dimension H3 of the third cylindrical portion 62 in the insertion / removal direction X may be approximately the same as the dimension H1 of the first cylindrical portion 32 in the insertion / removal direction X. Therefore, the dimension H3 of the third cylindrical portion 62 in the insertion / removal direction X is greater than the dimension H2 of the second cylindrical portion 42 in the insertion / removal direction X. As a result, when the third cylindrical portion 62 and the second cylindrical portion 42 are fitted together and the lower surface 62b of the third cylindrical portion 62 abuts against the upper surface 41a of the second flange portion 41, the lower surface 61b of the third flange portion 61 and the upper surface 42a of the second cylindrical portion 42 are spaced apart by the difference between the dimensions H3 and H2. Therefore, when the third cylindrical portion 62 and the second cylindrical portion 42 are fitted together, the surface area where the third jig 6 and the second jig 4 abut can be reduced.

[0044] A third insertion hole 63 through which the connecting member 5 can be inserted is provided in a side surface of the third cylindrical portion 62. Similar to the first cylindrical portion 32 and the second cylindrical portion 42, two third insertion holes 63 are provided in a side surface of the third cylindrical portion 62. Similarly to the first insertion hole 33, the third insertion hole 63 is formed as an elongated hole having a dimension h3 in the insertion / removal direction X that is larger than its dimension in the horizontal direction. The dimension h3 is preferably larger than the radial dimension h0 of the connecting member 5, and the horizontal dimension of the third insertion hole 63 is preferably approximately the same as the dimension h0 of the connecting member 5. This allows the connecting member 5 inserted into the third insertion hole 63 to move within the third insertion hole 63 along the insertion / removal direction X by the difference between the dimension h3 and the dimension h0 while its movement in the horizontal direction is restricted. Note that if the third cylindrical portion 62 is a columnar body, the third insertion hole 63 is preferably provided as a through-hole penetrating the columnar body. The shape of the long hole may be elliptical or rectangular.

[0045] [Valve body insertion method] Next, a valve element insertion method according to this embodiment will be described with reference to Figures 4 to 8. In this valve element insertion method, the following steps are performed in order: a first step of attaching a housing 7, an operating valve 8 that can open and close an opening 70 at the top of the housing 7, and a work case 9 that is connected via the operating valve 8 to a fluid pipe W as shown in Figure 4; a second step of opening and closing the operating valve 8 to drill a hole in the fluid pipe W through the opening 70 in the housing 7 as shown in Figure 5; a third step of assembling a valve element insertion / extraction device 10 and storing it in the work case 9 as shown in Figure 6; a fourth step of opening and closing the work valve 8 to insert a valve element V into the drilled portion of the fluid pipe W as shown in Figures 7 and 8; and a fifth step of removing the valve element insertion / extraction device 10 from the work case 9.

[0046] (first step) In the first step, as shown in FIG. 4, a housing 7 is installed around the outer periphery of the fluid pipe W to hermetically surround the fluid pipe W. The inner circumferential surface of the housing 7 may be provided with a valve seat against which the valve disc V abuts, and a guide portion that guides the valve disc V to an insertion position. The housing 7 also has a plurality of drain ports through which the fluid inside the housing 7 is discharged or introduced. As shown in FIG. 4, the drain ports include an upstream drain port 71 provided upstream of the insertion position of the valve disc V, and a downstream drain port 72 provided downstream of the insertion position of the valve disc V. The upstream drain port 71 and the downstream drain port 72 are provided in the lower part of the housing 7.

[0047] The housing 7 may be installed by welding together upper and lower divided bodies along the horizontal cross section of the fluid pipe W. After the housing 7 is installed, a hydraulic jig is attached to the opening of the housing 7 and a hydraulic pressure test is performed.

[0048] Next, a step of installing the working valve 8 in the opening 70 of the housing 7 is performed. The working valve 8 has a working valve main body 81 that opens and closes the opening 70 of the housing 7, and a working valve housing 82 that houses the working valve main body 81 so that it can move horizontally. The working valve housing 82 is attached to the housing 7 in a state that seals the connecting port portion 83 therein and the opening 70 of the housing 7. The working valve 8 can open and close the opening 70 by moving the working valve main body 81 horizontally between a valve closing position of the connecting port portion 83 and a valve opening position of the connecting port portion 83.

[0049] Next, a step of installing a work case 9 on top of the work valve 8 is carried out. The work case 9 accommodates a drilling machine and a valve body insertion / extraction device 10, which will be described later, in a sealed state.

[0050] (Second process) The second step involves installing the drilling device 91 in the work case 9 and drilling the fluid pipe W. As shown in Fig. 5, the drilling device 91 has a cylindrical hole saw 911, a center drill 912 disposed at the center of the hole saw 911, a drilling device main body 913 that houses the hole saw 911, the center drill 912, etc., and an operating handle 914 for operating the hole saw 911 and the center drill 912.

[0051] In the process of drilling the fluid pipe W, the work valve 8 is opened to open the opening 70, the operating handle 914 is operated to insert the hole saw 911 and center drill 912 into the housing 7 from their initial positions, and the hole saw 911 and center drill 912 are rotated and pressed against the outer wall of the fluid pipe W to drill a hole in the wall of the fluid pipe W. After drilling the fluid pipe W, the operating handle 914 is operated to hook chips and the like produced by drilling onto the center drill 912, and the hole saw 911 and center drill 912 are removed from the housing 7 and returned to their initial positions, and the work valve 8 is closed to close the opening 70. Thereafter, the fluid in the work case 9 is discharged, and the drilling device 91 is removed from the work case 9 and then removed. Note that chips and the like produced by drilling may be discharged to the outside of the housing 7 from the upstream drain port 71 or the downstream drain port 72 during the drilling process.

[0052] After the step of drilling the fluid pipe W is completed, a step of cleaning the inside of the housing 7 may be performed. In this step, the work case 9 may be removed, a cleaning device (not shown) may be installed above the work valve 8, and the work valve 8 may be opened to suck and remove foreign matter such as chips using the cleaning device. Alternatively, foreign matter such as chips may be removed by inserting a cleaning tool (not shown) into the inside of the housing 7 and discharging the chips from the upstream drain port 71 or the downstream drain port 72. After cleaning the inside of the housing 7, the work valve 8 is closed, the cleaning device and cleaning tool are removed, and the work case 9 is reinstalled.

[0053] (Third step) 1, 2 and 6, in the third step, a step of connecting the shaft portion 2 and the first jig 3, a step of connecting the valve body V and the second jig 4, and a step of connecting the first jig 3 and the second jig 4 are performed, and the valve body V is attached to the valve body insertion / extraction device 10. Then, a step of housing the valve body insertion / extraction device 10 inside the work case 9 is performed.

[0054] First, the lower surface 21b of the flange portion 21 of the shaft portion 2 is brought into contact with the upper surface 31a of the first flange portion 31 of the first jig 3, and the shaft portion 2 and the first jig 3 are connected with the fastening member 22. This step may be performed with the shaft portion 2 placed on a horizontal surface. Next, the upper surface Va of the valve body V is brought into contact with the lower surface 41b of the second flange portion 41, and the valve body V and the second jig 4 are connected with the fastening member 45. Next, with the valve body V in an upright position, the first cylindrical portion 32 is fitted into the second cylindrical portion 42 so that the central axis of the second cylindrical portion 42 of the second jig 4 is aligned with the central axis of the first cylindrical portion 32 of the first jig 3. Then, the connecting member 5 is inserted through the first insertion hole 33 and the second insertion hole 43, and the first jig 3 and the second jig 4 are connected. In this case, if the outer diameter L1 of the first cylindrical portion 32 and the inner diameter L2 of the second cylindrical portion 42 are approximately the same, the central axes of the first jig 3 and the second jig 4 are easily aligned, and the axis O of the shaft portion 2 and the central axis of the valve body V can be aligned, making it possible to insert the valve body V with high precision.

[0055] The process of attaching the valve body V to the valve body insertion / extraction device 10 may be performed in any order, such as by connecting the shaft portion 2 and the first jig 3, then connecting the first jig 3 and the second jig 4, and then connecting the second jig 4 and the valve body V. This process may be performed in parallel with the first and second processes, or may be performed before the first and second processes.

[0056] 6, the step of housing the valve body insertion / extraction device 10 inside the work case 9 is performed by connecting the upper opening of the work case 9 and the opening of the connection part 1 in a sealed state. As a result, a part of the shaft part 2, the first jig 3, the second jig 4, and the valve body V are housed in a sealed state inside the work case 9. At this time, the valve body insertion / extraction device 10 supports the valve body V at the contact surface between the lower end of the first insertion hole 33 and the connection member 5.

[0057] (Fourth step) 7, in the fourth step, a valve body V is inserted into the perforated portion of the fluid pipe W. First, the pressure equalizing pipe 73 connecting the housing 7 and the working case 9 is opened, sealing the inside of the working case 9 with the fluid, and equalizing the internal pressure of the housing 7 and the internal pressure of the working case 9. At this time, the working case 9 is deformed by expanding upward due to the pressure from the fluid.

[0058] Next, a step is performed in which the upstream drain port 71 and the downstream drain port 72 are connected by piping 76. This allows fluid to flow downstream of the insertion position of the valve disc V, thereby preventing excessive fluid pressure from acting on the upstream surface of the valve disc V when the valve disc V is inserted. Next, as shown in Figure 7, a step is performed in which the working valve 8 is opened and the stem portion 2 is advanced downward to insert the valve disc V to the insertion position. At this time, the lower surface 32b of the first tubular portion 32 and the upper surface 41a of the second flange portion 41 abut against each other, and force is transmitted from the stem portion 2 to the valve disc V via the abutting surfaces.

[0059] After the valve disc V has been inserted, the valve disc retainer 74 is inserted to fix the valve disc V, and a plug (not shown) is installed. The valve disc retainer 74 and the plug are inserted into an insertion hole formed in the upper part of the side of the housing 7 to prevent the valve disc V from floating up. This fixes the valve disc V in the housing 7.

[0060] (Fifth step) The fifth step involves draining the fluid from the work case 9 and removing the valve body insertion / extraction device 10 from the work case 9. If the step of draining the fluid from the work case 9 is performed with the lower surface 32b of the first cylindrical portion 32 and the upper surface 41a of the second flange portion 41 in contact with each other, stress acting on the work case 9 from the fluid in the work case 9 will be transmitted to the valve body V via the shaft portion 2 and will act on the connecting surfaces of the various parts of the valve body insertion / extraction device 10, making it difficult to disconnect the various parts. In addition, stress will be transmitted to the motor of the valve body insertion / extraction device 10 via the shaft portion 2, which could cause the motor to malfunction.

[0061] 8, the step of discharging the fluid from the working case 9 is performed in a state in which the lower surface 32b of the first cylindrical portion 32 and the upper surface 41a of the second flange portion 41 are spaced apart. The first insertion hole 33 of the first cylindrical portion 32 according to this embodiment is an elongated hole having a dimension h1 larger than the dimension h0 of the connecting member 5 in the insertion / removal direction X. When the lower surface 32b of the first cylindrical portion 32 and the upper surface 41a of the second flange portion 41 are in contact with each other, the center of the first insertion hole 33 in the insertion / removal direction X is positioned lower than the center of the second insertion hole 43. Therefore, the lower end of the connecting member 5 in the insertion / removal direction X is spaced apart from the lower edge of the first insertion hole 33. Therefore, when the first jig 3 and the second jig 4 are connected, the first jig 3 can be moved upward by the distance corresponding to the distance. Therefore, with the valve body insertion / extraction device 10 and the valve body V connected and with the valve body V fixed, the shaft portion 2 can be retracted upward to separate the lower surface 32b of the first tubular portion 32 from the upper surface 41a of the second flange portion 41, making it possible to provide an absorption margin that can absorb stress generated in the shaft portion 2 when fluid is discharged. As a result, the stress generated in the shaft portion 2 when the pressure inside the working case 9 is reduced is absorbed by the absorption margin, and no stress acts on the connecting surface between the first jig 3 and the second jig 4, improving the workability of the removal operation of the valve body insertion / extraction device 10 and making it possible to prevent breakdowns of the valve body insertion / extraction device 10.

[0062] Next, a step of removing the valve body insertion / extraction device 10 from the work case 9 is performed. First, the connection member 5 inserted into the first insertion hole 33 and the second insertion hole 43 is removed, thereby releasing the connection between the first jig 3 and the second jig 4. As a result, the shaft portion 2, the first jig 3, and the connection portion 1 are removed from the work case 9, with only the second jig 4 connected to the valve body V. Here, the stress generated in the shaft portion 2 when the fluid is discharged is absorbed by the absorption margin, so no stress acts on the contact surfaces between the first insertion hole 33 and the second insertion hole 43 and the connection member 5. Therefore, the connection member 5 can be easily removed.

[0063] The second jig 4 may be removed from the upper surface Va of the valve disc V, or may remain connected to the valve disc V. After the valve disc insertion / extraction device 10 is removed, a lid or the like may be placed on the upper opening of the work case 9. If the subsequent valve disc removal process is not performed, the second jig 4 is removed and a lid is placed on the opening of the housing 7 to complete the process.

[0064] [Valve body removal method] Next, a valve disc removal method according to this embodiment will be described with reference to Fig. 9. This valve disc removal method involves the following steps in order: a sixth step of attaching a housing 7 to a fluid pipe W, an operating valve 8 that can open and close an opening 70 at the top of the housing 7, and a work case 9 that is connected via the operating valve 8; a seventh step of assembling a valve disc insertion / extraction device 10 and storing it in the work case 9; an eighth step of opening and closing the operating valve 8 to remove the valve disc V from the perforated portion of the fluid pipe W as shown in Fig. 9; and a ninth step of removing the valve disc V from the valve disc insertion / extraction device 10.

[0065] (Sixth step) The sixth step is the same as the first step described above, and therefore its explanation will be omitted. Note that the valve body V inserted into the perforated portion of the fluid pipe W by the valve body insertion method may be removed after the need to close the fluid pipe W is no longer necessary.

[0066] (Seventh step) In the seventh step, the steps of connecting the shaft portion 2 and the third jig 6, connecting the valve body V and the second jig 4, and connecting the third jig 6 and the second jig 4 are performed, thereby connecting the valve body insertion / extraction device 10 and the valve body V (see Figure 3).

[0067] First, the valve body V and the second jig 4 are connected by fastening them together using the fastening member 45 while the lower surface 41b of the second flange portion 41 is in contact with the upper surface Va of the valve body V. If the second jig 4 is not removed in the fifth step described above, this step is omitted.

[0068] Next, a process of connecting the second jig 4 and the third jig 6 with the connecting member 5 is performed. In this embodiment, the outer diameter L3 of the third cylindrical portion 62 of the third jig 6 is smaller than the outer diameter L1 of the first cylindrical portion 32 of the first jig 3. Therefore, when the second jig 4 and the third jig 6 are fitted together, the horizontal distance between the second cylindrical portion 42 and the third cylindrical portion 62 is greater than the horizontal distance between the first cylindrical portion 32 and the second cylindrical portion 42 when the first jig 3 and the second jig 4 are fitted together. In other words, the horizontal distance between the outer peripheral surface of the third cylindrical portion 62 and the inner peripheral surface of the second cylindrical portion 42 is greater than the horizontal distance between the outer peripheral surface of the first cylindrical portion 32 and the inner peripheral surface of the second cylindrical portion 42, making it easier to fit the third jig 6 into the second jig 4. This improves the workability of the process of connecting the third jig 6 and the second jig 4. The step of connecting the second jig 4 and the third jig 6 may be carried out inside the work case 9.

[0069] Next, the upper opening of the work case 9 and the connection part 1 are joined in a sealed state, and the valve body insertion / extraction device 10 is connected to the work case 9. Then, the shank 2 is advanced downward in the work case 9, and the lower surface 21b of the flange part 21 of the shank 2 is brought into contact with the upper surface 61a of the third flange part 61. In this state, the shank 2 and the third jig 6 are fastened together with the fastening member 22, and the process of connecting the shank 2 and the third jig 6 is performed. Note that the valve body insertion / extraction device 10 may be connected to the work case 9 with the shank 2 and the third jig 6 connected, and the third jig 6 and the second jig 4 may be connected.

[0070] (Eighth process) In the eighth step, the pressures inside the housing 7 and the work case 9 are equalized, and the work valve 8 is opened and the valve body V is removed from the perforated portion of the fluid pipe W.

[0071] First, the pressure equalization pipe 73 connecting the housing 7 and the work case 9 is opened, and the work case 9 is filled with fluid to equalize the internal pressure of the housing 7 and the work case 9. Next, the work valve 8 is opened, the plug and the valve disc retainer 74 are returned to their initial positions, and the stem 2 is retracted upward to lift the valve disc V from its inserted position, thereby removing the valve disc V. As shown in FIG. 9 , the lower end of the connecting member 5 abuts against the lower edge of the third insertion hole 63, and the valve disc V is lifted while the second jig 4 and the third jig 6 are connected, and the valve disc V is removed from the bored portion of the fluid pipe W. The valve disc V removal step may be performed while the upstream drain port 71 and the downstream drain port 72 are connected by the pipe 76 or the like. This prevents fluid pressure from acting only on the upstream surface of the valve disc V.

[0072] (Ninth step) In the ninth step, the fluid inside the working case 9 is discharged, and the valve body V and the valve body inserting / extracting device 10 are removed.

[0073] In the process of discharging the fluid from the working case 9, when the fluid is discharged and stress is generated in the third jig 6 from the shaft portion 2, the third jig 6 moves downward by an amount equal to the stress. In this embodiment, the dimension h3 of the third insertion hole 63 of the third jig 6 in the insertion / removal direction X is larger than the dimension h0 of the connecting member 5, so that when the valve body V is pulled up, the upper end of the connecting member 5 is spaced apart from the upper edge of the third insertion hole 63. Therefore, even if the third jig 6 moves downward due to stress, the third jig 6 does not press the second jig 4, so stress does not act on the connection surface between the third jig 6 and the second jig 4, making it easy to release the connection between the third jig 6 and the second jig 4 and preventing malfunctions of the valve body insertion / removal device 10.

[0074] The step of removing the valve body V and the valve body inserting / extracting device 10 may be performed after the valve body V and the valve body inserting / extracting device 10 have been removed from the work case 9. The removal of the various parts of the valve body inserting / extracting device 10 may be performed in any order.

[0075] After the valve body V and the valve body insertion / removal device 10 are removed, the work case 9 is removed, an inner plug (not shown) that closes the opening 70 of the housing 7 is inserted into the housing 7, and a lid is installed on the opening 70 of the housing 7 in place of the work valve 8.

[0076] Other Embodiments (a) In the above embodiment, the outer diameter L1 of the first cylindrical portion 32 and the outer diameter L3 of the third cylindrical portion 62 are smaller than the inner diameter L2 of the second cylindrical portion 42. However, the inner diameters of the first cylindrical portion 32 and the third cylindrical portion 62 may be larger than the outer diameter of the second cylindrical portion 42. In this case, the second cylindrical portion 42 may be a columnar body that fits inside the first cylindrical portion 32 and the third cylindrical portion 62.

[0077] (b) In the above embodiment, the dimension H1 in the X direction of the first cylindrical portion 32 is larger than the dimension H2 in the X direction of the second cylindrical portion 42. However, the dimensions H1 and H2 may be substantially the same. In this case, the first jig 3 and the second jig 4 may be connected in a state where the lower surface 32b of the first cylindrical portion 32 and the lower surface 31b of the first flange portion 31 do not come into contact with the second jig 4.

[0078] (c) In the above embodiment, the dimension H1 of the first cylindrical portion 32 in the insertion / removal direction X is larger than the dimension H2 of the second cylindrical portion 42 in the insertion / removal direction X, but the dimension H1 may be smaller than the dimension H2. The lower surface 31b of the first flange portion 31 and the upper surface 42a of the second cylindrical portion 42 abut against each other, allowing the first jig 3 to apply force to the second jig 4.

[0079] (d) In the above embodiment, the upstream drain port 71 and the downstream drain port 72 are connected by piping 76 during the drilling process to discharge chips and the like and when inserting the valve body V, but as shown in Figures 10 and 11, a branch piping B may be formed after inserting or removing the valve body V.

[0080] In the embodiment (d), as shown in FIGS. 10 and 11 , the housing 7 includes a housing body 7a having a valve seat that contacts the valve element V and a housing side portion 7b that covers the outer periphery of the fluid pipe W. The housing body 7a and the housing side portion 7b are joined by welding. In this embodiment, the upstream drain port 71 and a branch opening 77 having a diameter larger than that of the upstream drain port 71 are each provided in a location other than the welded portion of the housing body 7a. The branch opening 77 may be obtained by expanding the diameter of the downstream drain port 72, or the downstream drain port 72 may be used as the branch opening 77. By using the branch opening 77 to form the branch pipe B on the fluid pipe W, it is not necessary to form an opening or the like in the housing 7 for forming the branch pipe B, thereby simplifying the structure of the housing 7. Furthermore, by providing the upstream drain port 71 and the branch opening 77 in a location other than the welded portion of the housing body 7a, fluid pressure does not act on the welded portion, and the strength of the housing 7 can be maintained.

[0081] The branch pipe B may be formed by connecting the branch pipe B to the gate valve Ba connected to the branch opening 77 after the valve body V has been inserted or removed.

[0082] (e) In the above embodiment, the valve element V is illustrated as a shutoff valve that blocks the flow of the fluid pipe W. However, it may also be an on-off valve such as a changeover valve, a sluice valve, or a butterfly valve. As shown in FIG. 12 , a valve-element-related member Vc, such as a valve stem or a reducer, may be disposed at the upper end of the valve element V. When the valve-element-related member Vc is disposed at the upper end of the valve element V, the second flange portion 41 may be formed with a through-hole 46 that penetrates from the upper surface 41 a to the lower surface 41 b thereof and through which the valve-element-related member Vc can be inserted when the second flange portion 41 is disposed at the upper end of the valve element V. The size of the through-hole 46 is not particularly limited as long as the lower surface 32 b of the first tubular portion 32 can abut against the upper surface 41 a of the second flange portion 41, and can be changed appropriately depending on the size of the valve-element-related member Vc. 12, in a state in which the first jig 3 and the second jig 4 are connected to the valve body V, the insertion holes 33, 43 are provided above the upper end of the valve-body-related member Vc. If the insertion holes 33, 43 are positioned above the upper end of the valve-body-related member Vc, it is possible to avoid interference between the connection member 5 and the valve-body-related member Vc when the connection member 5 is inserted through the insertion holes 33, 43.

[0083] (f) In the above embodiment, a pair of first insertion holes 33 or a pair of second insertion holes 43 corresponding to one connecting member 5 is provided in the side surfaces of the first cylindrical portion 32 and the second cylindrical portion 42. However, two or more pairs of insertion holes 33, 43 corresponding to two or more connecting members 5 may be provided. In the example shown in FIGS. 13 and 14 , two pairs of first insertion holes 33, 33 or two pairs of second insertion holes 43, 43 corresponding to two connecting members 5 are provided in the side surfaces of the first cylindrical portion 32 and the second cylindrical portion 42. That is, the cylindrical portions 32, 42 are formed so that two connecting members 5, 5 can be inserted therethrough. When the first jig 3 and the second jig 4 are connected to the valve body V, each of the two pairs of first insertion holes 33, 33 and second insertion holes 43, 43 is preferably provided at a position overlapping the valve-body-related member Vc in a side view, and at a position sandwiching the valve-body-related member Vc when viewed in the insertion / removal direction of the valve body V. The two pairs of first insertion holes 33, 33 and the two pairs of second insertion holes 43, 43 are preferably provided at positions symmetrical with respect to the valve-disc-related member Vc. Furthermore, the two pairs of first insertion holes 33, 33 and the two pairs of second insertion holes 43, 43 overlap when viewed in the insertion direction of the connecting member 5 when the first jig 3 and the second jig 4 are connected to the valve disc V. If the insertion holes 33, 43 are arranged in this manner, interference between the valve-disc-related member Vc and the connecting member 5 can be avoided even when the valve-disc-related member Vc is arranged above the valve disc V, and increases in the dimensions of the first jig 3, the second jig 4, the work case 9, and the like can be suppressed. This makes it possible to provide a valve disc insertion / extraction device 10 that suppresses an increase in the insertion stroke of the valve disc V and can be used for different types of valve discs V. The positions of the insertion holes 33, 43 in the cylindrical portions 32, 42 are not particularly limited as long as the first jig 3 and the second jig 4 can stably support the valve body V. Furthermore, in this embodiment, an example has been shown in which the valve body-related member Vc is provided along the axis O, but the valve body-related member Vc does not have to be provided along the axis O, and may be provided at a position eccentric to the axis O. [Industrial Applicability]

[0084] INDUSTRIAL APPLICABILITY The present invention can be used for a valve body insertion / removal device, a valve body insertion method, and a valve body removal method for inserting and removing a valve body into and from a perforated portion of a fluid pipe under an uninterrupted flow condition. [Explanation of symbols]

[0085] 2: Shaft 3: First jig 4: Second jig 5: Connection parts 6: Third jig 7: Housing 8: Working valve 9: Work case 10: Valve body insertion / extraction device 31: First flange 31b: Bottom surface 32: First cylindrical portion 32b: Bottom surface 33: First insertion hole (insertion hole) 41: Second flange part 41a:Top surface 42:Second cylindrical part 43: Second insertion hole (insertion hole) 46:Through hole 61: Third flange 61b: Bottom surface 62:Third cylindrical part 71: Upstream drain port (drain port) 72: Downstream drain port (drain port) V: Valve body Vc: Valve body related parts W:Fluid tube X: Insertion / extraction direction h0: Dimension (diameter) h1: Dimensions h2: Dimensions

Claims

1. A valve body insertion / removal device for inserting and removing a valve body into a perforated portion of a fluid pipe under an uninterrupted flow condition, a shaft portion that can advance and retreat along the insertion and removal direction of the valve body; a first jig including a first flange portion connected to a lower end of the shaft portion and a first cylindrical portion extending downward from a lower surface of the first flange portion; a second jig including a second flange portion connected to an upper end of the valve body, and a second cylindrical portion extending upward from an upper surface of the second flange portion and capable of fitting with the first cylindrical portion; a rod-shaped connecting member that connects the first jig and the second jig when the first cylindrical portion and the second cylindrical portion are fitted together;

2. The first cylindrical portion and the second cylindrical portion have insertion holes through which the connecting member is inserted, The valve body insertion / extraction device according to claim 1 , wherein the insertion hole of either the first cylindrical portion or the second cylindrical portion is an elongated hole whose dimension in the insertion / extraction direction is larger than the diameter of the connecting member.

3. the second flange portion has a through hole through which a valve-element-related member disposed at the upper end of the valve element is inserted, 3. The valve body inserting / extracting device according to claim 2, wherein the insertion hole is formed at a position that allows interference between the connecting member and the valve body-related member to be avoided.

4. At least two or more insertion holes through which at least two or more of the connecting members are inserted are formed in the first cylindrical portion and the second cylindrical portion, The valve body insertion / extraction device according to claim 3 , wherein the at least two or more insertion holes are formed at positions sandwiching the valve body-related member when viewed in the insertion / extraction direction.

5. The valve body insertion / extraction device according to claim 2, wherein when the valve body is inserted, either the lower surface of the first flange portion or the lower surface of the first cylindrical portion abuts against the second jig.

6. A valve body insertion method using the valve body insertion / extraction device according to any one of claims 1 to 5, a step of disposing a housing that hermetically surrounds the fluid pipe and a work case that is connected to the housing via a work valve and can house the valve body insertion / extraction device in a hermetically sealed state; a step of fitting the first cylindrical portion and the second cylindrical portion together to connect the first jig and the second jig with the connecting member, and storing the valve body insertion / extraction device in the work case; a step of sealing the work case and inserting the valve body into the perforated portion of the fluid pipe while the lower surface of either the first flange portion or the lower surface of the first cylindrical portion is in contact with the second jig; After inserting the valve body, the fluid in the work case is drained while the lower surface of the first flange portion and the lower surface of the first cylindrical portion are separated from the second jig, and the valve body insertion / extraction device is removed from the work case.

7. 7. The valve body inserting method according to claim 6, wherein the step of removing the valve body inserting / extracting device from the work case is performed by removing the connecting member.

8. The housing has a plurality of drain ports for discharging or introducing fluid, 7. The valve body insertion method according to claim 6, wherein the step of inserting the valve body into the perforated portion is performed in a state in which the drain port provided upstream of the insertion position of the valve body and the drain port provided downstream of the insertion position are in communication with each other.

9. a third jig including a third flange portion connected to a lower end of the shaft portion, and a third cylindrical portion extending downward from a lower surface of the third flange portion and capable of fitting with the second cylindrical portion; 6. A valve body removal method using a valve body insertion / extraction device according to any one of claims 1 to 5, wherein a separation distance between the second cylindrical portion and the third cylindrical portion in a plane perpendicular to the insertion / extraction direction when the second cylindrical portion and the third cylindrical portion are fitted together is greater than a separation distance between the first cylindrical portion and the second cylindrical portion in the plane when the first cylindrical portion and the second cylindrical portion are fitted together, a step of disposing a housing that hermetically surrounds the fluid pipe and a work case that is connected to the housing via a work valve and can house the valve body insertion / extraction device in a hermetically sealed state; a step of connecting the second jig connected to the upper end of the valve body and the third jig with the connecting member, and connecting the third jig and the shaft portion; and removing the valve body from the perforated portion of the fluid pipe while sealing the work case.

Images