Expansion member of watertightness test device

Abstract

To provide an expansion member of a watertightness test device, which reduces labor when a watertightness test is conducted on a connection part of pipes.SOLUTION: An expansion member 20 of a watertightness test device includes: a belt-like member 21 formed of a flexible member; a guided part provided on one side of the belt-like member 21 in a longitudinal direction; a guide part which is provided on the other side of the belt-like member 21 in the longitudinal direction and which guides the guided part in the longitudinal direction of the belt-like member 21; and spacer receiving parts which are respectively provided on the one and other sides of the belt-like member 21 in the longitudinal direction and which receive a spacer for maintaining an expanded state of the belt-like member 21.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present disclosure relates to an extension member of a watertightness test apparatus used when performing a watertightness test on a connection part of a pipe.

Background Art

[0002] For example, when connecting a plurality of pipes on-site to form a water passage or the like, it is necessary to confirm on-site whether the watertightness of the connection part of the pipe satisfies predetermined requirements. When making this confirmation, for example, a watertightness test apparatus as disclosed in Patent Document 1 is used. The watertightness test apparatus of Patent Document 1 includes a rubber sleeve that covers the connection part of the pipe from the inside, and two flexible band-like members arranged in the longitudinal direction of the pipe on the inner peripheral side of the rubber sleeve. During the test, the rubber sleeve is brought into close contact with the inner peripheral surface of the pipe by expanding the flexible band-like members in diameter, and a test fluid is injected at a predetermined pressure between the rubber sleeve and the inner peripheral surface of the pipe from a water injection port provided in the rubber sleeve. Based on the subsequent pressure change of the test fluid, it is possible to determine whether the watertightness satisfies the predetermined requirements.

[0003] The flexible band-like member of Patent Document 1 is divided into a plurality of divided members in the circumferential direction and has an assembled hinge that connects adjacent divided members in the circumferential direction. This makes it possible to fold the flexible band-like member.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Incidentally, although it varies depending on the site and the pipes used, the pipe connections will be present, for example, about every 5 m. And depending on the site, the pipe extension may be several hundred meters or more. In such a case, it is necessary to repeat the watertightness test inside the pipe dozens or even hundreds of times.

[0006] Assuming the case of using the flexible band-shaped member of Patent Document 1, after the watertightness test of one connection part is completed, the flexible band-shaped member is folded and then carried to the next connection part and unfolded there, and the above-mentioned number of times of operation is repeated. Therefore, the labor of the operator increases.

[0007] Also, the flexible band-shaped member needs to have its strength increased so that the rubber sleeve can be brought into close contact with the inner peripheral surface of the pipe even when a high water pressure acts during the watertightness test, that is, so that a high expansion force can be obtained. For this reason, the flexible band-shaped member is generally made of a metal such as steel, is thick, and is designed to have a width equal to or greater than a predetermined value. Moreover, when the inner diameter of the pipe is about 1 m or more, the diameter of the flexible band-shaped member also needs to be increased according to the inner diameter of the pipe. In that case, the weight of each divided member constituting the flexible band-shaped member of Patent Document 1 becomes heavy. When the weight of each divided member is heavy, the force required to rotate each divided member upward around the hinge axis when unfolding from the folded state becomes large, and a large amount of labor is required of the operator, which also becomes a factor increasing the labor of the operator.

[0008] The present disclosure is made in view of such a point, and its object is to reduce the labor when performing the watertightness test of the pipe connection part.

Means for Solving the Problems

[0009] To achieve the above object, in one aspect of the present disclosure, an expansion member of a watertightness test device for pressing an annular covering member of a watertightness test device for testing the watertightness of a connection portion between a first pipe and a second pipe against the inner peripheral surface of the pipe can be premised. The expansion member of the watertightness test device includes a belt-like member formed of a flexible member having a curved shape extending along the inner peripheral surface of the annular covering member, a guided portion provided on one longitudinal side of the belt-like member, a guiding portion provided on the other longitudinal side of the belt-like member for guiding the guided portion in the longitudinal direction of the belt-like member, and spacer receiving portions provided on one and the other longitudinal sides of the belt-like member for receiving spacers for holding the expanded state of the belt-like member.

[0010] According to this configuration, after the annular covering member is installed so as to span from the inner peripheral surface of the first pipe to the inner peripheral surface of the second pipe, when the belt-like member is disposed inside the annular covering member and then expanded and the spacers are received by the spacer receiving portions, the belt-like member is held in the expanded state, so that the annular covering member adheres closely to the inner peripheral surfaces of the first pipe and the second pipe. Then, a test fluid is supplied to the space formed between the outer peripheral surface of the annular covering member and the first pipe and the second pipe, and the result of the watertightness test is obtained by measuring the pressure change of the test fluid.

[0011] After performing the watertightness test as described above at one connection portion, when performing the watertightness test at another connection portion, it is necessary to reduce the diameter of the belt-like member in the expanded state. At this time, since the guided portion of the belt-like member is guided in the longitudinal direction of the belt-like member by the guiding portion, the operation of reducing the diameter of the belt-like member becomes easy. By reducing the diameter of the belt-like member, the operation of transporting the inside of the pipe to another connection portion also becomes easy. When the belt-like member is expanded after being transported to another connection portion, since the guided portion of the belt-like member is guided in the direction opposite to the diameter-reducing direction by the guiding portion, the operation of expanding the diameter of the belt-like member becomes easy. According to this configuration, all operations such as the operation of reducing the diameter of the belt-like member, the operation of transporting it, and the operation of expanding the diameter become easy, so that even if it is necessary to repeat the watertightness test dozens of times or more than a hundred times, it is possible to significantly reduce the labor.

[0012] The internal guided portion may be constituted by a shaft portion extending in the width direction of the belt-like member. In this case, the guiding portion can be constituted by a slit extending in the longitudinal direction of the belt-like member and into which the shaft portion is inserted. According to this configuration, while having a simple configuration of inserting the shaft portion into the slit, the guiding portion can reliably guide the belt-like member in the longitudinal direction.

[0013] The slit may be formed in a plate portion. In this case, the plate portion can have a shape that protrudes toward the inside of the curved shape in the belt-like member and extends in the longitudinal direction of the belt-like member.

[0014] The shaft portion may be provided so as to protrude in the width direction from one end portion in the width direction on one side in the longitudinal direction of the belt-like member. In this case, the plate portion can be made to protrude from one end portion in the width direction on the other side in the longitudinal direction of the belt-like member toward the inside of the curved shape. According to this configuration, since the shaft portion and the plate portion are arranged at one end portion in the width direction of the belt-like member, the shaft portion and the plate portion are less likely to get in the way when installing the spacer in the spacer receiving portion, and the workability of installing the spacer is improved.

[0015] A retaining portion formed wider than the width of the slit may be provided at the tip of the shaft portion. Thereby, it is possible to prevent the shaft portion from accidentally coming out of the slit, so that the operations of expanding the diameter and reducing the diameter can be performed more easily.

[0016] A thread groove may be formed on the outer peripheral surface of the shaft portion. In this case, the portion of the shaft portion where the thread groove is formed can be screwed into a screwing portion provided on one side in the longitudinal direction of the belt-like member. Then, by rotating the shaft portion in the screwing direction, the edge portion of the slit in the plate portion can be fastened by the retaining portion and the member having the screwing portion. Thereby, the guiding portion and the internal guided portion do not move relative to each other, and the belt-like member can be held in a state where the diameter is reduced. Therefore, when transporting the belt-like member in a state where the diameter is reduced, the belt-like member does not accidentally expand in diameter, and the transport operation becomes even easier.

Advantages of the Invention

[0017] As described above, since the object to be guided is provided on one longitudinal side of the strip-shaped member extending along the inner peripheral surface of the annular covering body, and a guiding portion for guiding the object to be guided in the longitudinal direction of the strip-shaped member is provided on the other side, the labor for performing the watertightness test of the connection portion of the pipe can be reduced.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

BEST MODE FOR CARRYING OUT THE INVENTION

[0019] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the following description of the preferred embodiments is merely illustrative in nature and is not intended to limit the present invention, its applications, or its uses.

[0020] FIG. 1 is a diagram for explaining the use of a watertightness test apparatus 1 to which a waterstop structure according to an embodiment of the present invention is applied. This watertightness test apparatus 1 is an apparatus used to confirm on-site whether the watertightness of the connection portion of pipes 101 and 102 satisfies predetermined requirements when a plurality of pipes 101 and 102 are connected on-site to form a waterway or the like. In this embodiment, the case where the first pipe 101 and the second pipe 102 are connected will be described. However, the number of pipes to be connected is not limited to two and may be any number, and the waterstop performance of the connection portion between any two pipes can be confirmed by the watertightness test apparatus 1. Further, in this embodiment, the case where both the first pipe 101 and the second pipe 102 are circular pipes will be described. However, the present invention can also be applied when the waterstop performance of the connection portion of pipes other than circular pipes is confirmed by the watertightness test apparatus 1.

[0021] The first pipe 101 and the second pipe 102 may be, for example, pipes made of concrete, pipes made of resin, or pipes made of metal. Also, the first pipe 101 and the second pipe 102 may be existing pipes that have already been installed and are in use, or new pipes.

[0022] The watertightness test device 1 includes an annular covering 10, a first expansion member 20, a second expansion member 30, a fluid supply unit 40, a pipe 50, a supply and discharge device 60, and a measuring instrument 70. The annular covering 10 is formed so as to extend from the inner peripheral surface of the first pipe 101 to the inner peripheral surface of the second pipe 102, and is composed of a rubber member having an annular shape along both of the inner peripheral surfaces, and has water impermeability. The outer peripheral length of the annular covering 10 corresponds to the inner peripheral lengths of the first pipe 101 and the second pipe 102 for which the watertightness test is to be performed. If the first pipe 101 and the second pipe 102 have a small diameter, the outer peripheral length of the annular covering 10 is shortened accordingly, and if the first pipe 101 and the second pipe 102 have a large diameter, the outer peripheral length of the annular covering 10 is lengthened accordingly. The same applies to the peripheral lengths of the first expansion member 20 and the second expansion member 30.

[0023] Figure 2 shows cross-sections of the annular covering 10, the first expansion member 20, the second expansion member 30, the first pipe 101, and the second pipe 102. In this Figure 2, a gap S is formed between the first pipe 101 and the second pipe 102, but this gap S may not be formed. The width direction of the annular covering 10 is the left-right direction in Figure 2 and corresponds to the direction in which the first pipe 101 and the second pipe 102 are arranged (the pipe axis direction). The thickness direction of the annular covering 10 is the up-down direction in Figure 2 and corresponds to the wall thickness direction of the first pipe 101 and the second pipe 102.

[0024] On the outer peripheral surface (the lower surface in FIG. 2) of the annular covering 10, a plurality of first ridge portions 11 are formed on the side of the first tube 101. The plurality of first ridge portions 11 are arranged at intervals in the width direction of the annular covering 10. Each first ridge portion 11 extends continuously over the entire circumference in the circumferential direction of the annular covering 10. On the side of the second tube 102 on the outer peripheral surface of the annular covering 10, a plurality of second ridge portions 12 are formed in the same manner as the first ridge portions 11. The plurality of second ridge portions 12 are arranged at intervals in the width direction of the annular covering 10. Each second ridge portion 12 extends continuously over the entire circumference in the circumferential direction of the annular covering 10. The first ridge portions 11 and the second ridge portions 12 are in contact with the inner peripheral surfaces of the first tube 101 and the second tube 102, respectively. The first ridge portions 11 and the second ridge portions 12 may be formed as necessary and may be omitted.

[0025] At the end of the annular covering 10 on the side of the first tube 101, a first lip-shaped portion 13 is formed. The first lip-shaped portion 13 protrudes in a direction approaching the inner peripheral surface of the first tube 101 and extends continuously over the entire circumference in the circumferential direction of the annular covering 10. At the end of the annular covering 10 on the side of the second tube 102, a second lip-shaped portion 14 is formed. The second lip-shaped portion 14 protrudes in a direction approaching the inner peripheral surface of the second tube 102 and extends continuously over the entire circumference in the circumferential direction of the annular covering 10. The first lip-shaped portion 13 and the second lip-shaped portion 14 are in contact with the inner peripheral surfaces of the first tube 101 and the second tube 102, respectively. The first lip-shaped portion 13 and the second lip-shaped portion 14 may be formed as necessary and may be omitted.

[0026] On the inner peripheral surface (the upper surface in FIG. 2) of the annular covering 10, a first recess 15 is formed on the side of the first tube 101. The first recess 15 is continuously formed over the entire circumference in the circumferential direction of the annular covering 10, and a first expansion member 20 is adapted to fit into the first recess 15. The first recess 15 and the first ridge portion 11 are arranged to correspond to each other in the front-back direction (thickness direction) of the annular covering 10, and the first ridge portion 11 is located directly behind the first recess 15.

[0027] A second recess 16 is formed on the inner peripheral surface of the annular covering 10 on the side of the second tube 102. The second recess 16 is continuously formed over the entire circumference in the circumferential direction of the annular covering 10, and a second expansion member 30 is fitted into the second recess 16. The second recess 16 and the second protrusion 12 are arranged to correspond to each other in the front-back direction (thickness direction) of the annular covering 10, and the second protrusion 12 is located directly behind the second recess 16.

[0028] In a portion closer to the center in the width direction than the first recess 15 of the annular covering 10, a first bulging portion 10a bulging inward of the annular covering 10 is formed. Also, in a portion closer to the center in the width direction than the second recess 16 of the annular covering 10, a second bulging portion 10b bulging inward of the annular covering 10 is formed. Further, in a portion closer to the center in the width direction than the first bulging portion 10a of the annular covering 10, a third bulging portion 10c bulging outward of the annular covering 10 is formed. Additionally, in a portion closer to the center in the width direction than the second bulging portion 10b of the annular covering 10, a fourth bulging portion 10d bulging outward of the annular covering 10 is formed. The first bulging portion 10a, the second bulging portion 10b, the third bulging portion 10c, and the fourth bulging portion 10d are continuous over the entire circumference in the circumferential direction of the annular covering 10. The center in the width direction of the annular covering 10 is the portion between the third bulging portion 10c and the fourth bulging portion 10d.

[0029] The annular covering 10 includes a reinforcing material 17. The reinforcing material 17 is composed of, for example, a mesh made of fibers having almost no stretchability such as aramid fibers. The reinforcing material 17 is provided along the inner peripheral surface of the annular covering 10 over the entire circumference and is continuously provided from inside the first recess 15 to inside the second recess 16. The reinforcing material 17 may be provided as needed, and the range in which the reinforcing material 17 is provided can also be set to an arbitrary range. In this embodiment, the reinforcing material 17 is provided so as to include the portion where the fluid supply portion 40 is provided (the center in the width direction of the annular covering 10). The reinforcing material 17 may be embedded in the middle portion in the thickness direction of the annular covering 10.

[0030] A fluid supply portion 40 is provided at the central portion in the width direction of the annular covering 10. The fluid supply portion 40 is a portion for supplying a test fluid from the outside to a space R formed between the outer peripheral surface of the annular covering 10 and the first pipe 101 and the second pipe 102. When a gap S is formed between the first pipe 101 and the second pipe 102, the gap S is included in the space R. Further, the space R is formed between the first ridge portion 11 and the second ridge portion 12. The test fluid is, for example, water, but is not limited to water, and various fluids can be used as the test fluid.

[0031] As shown in FIG. 3, the fluid supply portion 40 includes a cylindrical member 41 formed in a cylindrical shape, an outer peripheral side sealing member 42, an outer peripheral side pressing member 43, an inner peripheral side sealing member 44, an inner peripheral side pressing member 45, and a fastening member 46. As shown in FIG. 4, in the central portion in the width direction of the annular covering 10, a through hole 18 penetrating the annular covering 10 in the thickness direction is formed in a portion where the fluid supply portion 40 is provided. The through hole 18 is circular, and the diameter of the through hole 18 is set to be the same as or smaller than the outer diameter of the cylindrical member 41.

[0032] The cylindrical member 41 is a member inserted into the through hole 18 of the annular covering 10, and is made of a member having high rigidity and high strength such as metal, for example. The length of the cylindrical member 41 is set to be longer than the thickness dimension of the annular covering 10, and both axial end portions of the cylindrical member 41 in the state of being inserted into the through hole 18 protrude from the inner peripheral surface and the outer peripheral surface of the annular covering 10, respectively. Both axial end faces of the cylindrical member 41 are open.

[0033] A thread groove 41a is formed on the outer peripheral surface of the cylindrical member 41. The entire outer peripheral surface of the cylindrical member 41 is threaded, and the thread groove 41a is continuously formed from one axial end portion to the other end portion of the cylindrical member 41. Incidentally, the thread groove 41a may not be formed in the axial intermediate portion of the cylindrical member 41. In this case, the thread groove 41a is formed in one axial end side portion and the other end side portion of the cylindrical member 41.

[0034] The outer peripheral pressing member 43 is made of a metal material that presses around the through-hole 18 on the outer peripheral surface of the annular covering 10, and has an outer peripheral insertion hole 43a through which the cylindrical member 41 is inserted. The outer shape of the outer peripheral pressing member 43 is circular. Also, the outer peripheral insertion hole 43a is circular, and the diameter of the outer peripheral insertion hole 43a is set to be slightly larger than the outer diameter of the cylindrical member 41. Concavities and convexities may be provided on the surface of the outer peripheral pressing member 43 on the side of the annular covering 10. Thereby, stress concentration points can be provided by the outer peripheral pressing member 43, and the water stoppage performance can be further improved.

[0035] Examples of the metal material constituting the outer peripheral pressing member 43 include iron, stainless steel, aluminum alloy, etc., but are not limited thereto, and any material having a strength such that it hardly deforms due to the fastening force of the fastening member 46 may be used. Also, the thickness of the outer peripheral pressing member 43 can be, for example, 0.5 mm or more, or 1.0 mm or more, but is not particularly limited, and it may have a thickness such that it hardly deforms due to the fastening force of the fastening member 46. Also, the outer diameter of the outer peripheral pressing member 43 is set to be 2 times or more, or 3 times or more the diameter of the through-hole 18.

[0036] The inner peripheral pressing member 45 is made of a metal material that presses around the through-hole 18 on the inner peripheral surface of the annular covering 10, and has an inner peripheral insertion hole 45a through which the cylindrical member 41 is inserted. In the present embodiment, since the inner peripheral pressing member 45 and the outer peripheral pressing member 43 are made of the same member, the outer diameter, inner diameter, and wall thickness of the inner peripheral pressing member 45 and the outer peripheral pressing member 43 are equal. Note that the inner peripheral pressing member 45 and the outer peripheral pressing member 43 may be constituted by members having different shapes. For example, the outer diameter of one may be smaller than the outer diameter of the other, the inner diameter of one may be smaller than the inner diameter of the other, or the wall thickness of one may be thinner than the wall thickness of the other.

[0037] The outer peripheral sealing member 42 is a member provided between the outer peripheral pressing member 43 and around the through hole 18 on the outer peripheral surface of the annular covering body 10, and is made of vulcanized rubber or thermoplastic rubber. In this embodiment, the outer peripheral sealing member 42 has a disc shape and has an outer diameter equal to the outer diameter of the outer peripheral pressing member 43. An insertion hole 44a through which the cylindrical member 41 is inserted is formed in the central portion of the outer peripheral sealing member 42. The insertion hole 44a is circular. The thickness of the outer peripheral sealing member 42 may be the same as the thickness of the outer peripheral pressing member 43, may be thicker than the outer peripheral pressing member 43, or may be thinner than the outer peripheral pressing member 43.

[0038] The inner peripheral sealing member 44 is a member provided between the inner peripheral pressing member 45 and around the through hole 18 on the outer peripheral surface of the annular covering body 10, and can be the same member as the outer peripheral sealing member 42. The thickness of the inner peripheral sealing member 44 may be the same as the thickness of the inner peripheral pressing member 45, may be thicker than the inner peripheral pressing member 45, or may be thinner than the inner peripheral pressing member 45. Only one of the inner peripheral sealing member 44 and the outer peripheral sealing member 42 may be provided.

[0039] The fastening member 46 is a member for fastening the outer peripheral pressing member 43 and the inner peripheral pressing member 45 in a direction approaching each other. That is, the length of the cylindrical member 41 is set to be longer than the dimension obtained by adding the thickness of the annular covering body 10, the thickness of the outer peripheral sealing member 42, the thickness of the outer peripheral pressing member 43, the thickness of the inner peripheral sealing member 44, and the thickness of the inner peripheral pressing member 45. And the fastening member 46 includes a nut 47 and a socket 48 that are screwed into the screw groove 41a of the cylindrical member 41. The nut 47 is a member that is screwed onto the outer peripheral side of the annular covering body 10 in the cylindrical member 41 and is arranged so as to contact the outer peripheral pressing member 43. The nut 47 is composed of a thin nut having an axial dimension of, for example, 10 mm or less, or 8 mm or less. A groove extending in the radial direction may be formed on the surface of the nut 47 on the side opposite to the outer peripheral pressing member 43. Thereby, the test fluid flowing out from the cylindrical member 41 can be supplied to the space R through the groove of the nut 47.

[0040] Socket 48 is formed as a cylindrical member made of the same metal as the cylindrical member 41 and is composed of a member with both ends open. Threads that engage with the thread groove 41a of the cylindrical member 41 are formed on the inner peripheral surface of the socket 48. One end of the socket 48 is screwed into the inner peripheral side of the annular covering 10 in the cylindrical member 41 and communicates with the cylindrical member 41. As a result, the space R is connected to the socket 48 via the cylindrical member 41, enabling the flow of fluid from the socket 48 to the space R. As shown by the phantom line in FIG. 2, one end of a test fluid pipe 50 is connected to the other end of the socket 48.

[0041] By tightening the socket 48 and the nut 47, the outer peripheral pressing member 43 and the inner peripheral pressing member 45 approach each other. When the outer peripheral pressing member 43 and the inner peripheral pressing member 45 approach each other, the outer peripheral sealing material 42 and the inner peripheral sealing material 44 are pressed in the thickness direction and deformed. As a result, a part of the outer peripheral sealing material 42 and the inner peripheral sealing material 44 is filled into the through hole 18 and intervenes between the inner peripheral surface of the through hole 18 and the outer peripheral surface of the cylindrical member 41.

[0042] The pipe 50 shown in FIG. 1 is connected to the socket 48 as described above and is also connected to the supply and discharge device 60. The supply and discharge device 60 incorporates a pump (not shown) that feeds water as a test fluid to the pipe 50. When an operator performs a predetermined operation, the pump operates to feed water to the pipe 50. The pressure of the water can be adjusted arbitrarily. Further, a measuring instrument 70 is connected to the pipe 50, enabling the pressure of the test fluid in the pipe 50 to be constantly measured. The operator can grasp the pressure change of the test fluid by looking at the display of the measuring instrument 70. After the test, the test fluid can be discharged from the space R by the supply and discharge device 60.

[0043] Note that the measuring instrument 70 may be an electronic device. In this case, the pressure change of the test fluid can be automatically recorded, and based on the record, it can be confirmed whether the watertightness satisfies the predetermined requirements.

[0044] FIG. 5 is a front view of the first expansion member 20, that is, a view seen along the pipe axis direction during installation. The first expansion member 20 is a member for pressing the annular cover 10 of the watertightness test device 1 against the inner peripheral surface of the first pipe 101. The second expansion member 30 is configured in the same manner as the first expansion member 20 and is a member for pressing the annular cover 10 against the inner peripheral surface of the second pipe 102. Hereinafter, the structure of the first expansion member 20 will be described in detail.

[0045] The first expansion member 20 includes a belt-like member 21 formed of a member having a curved shape extending along the inner peripheral surface of the annular cover 10 and having flexibility. The circumferential direction of the belt-like member 21 is the longitudinal direction of the belt-like member 21. Also, the width direction of the belt-like member 21 is a direction that coincides with the pipe axis direction during installation. Further, since the belt-like member 21 has a curved shape extending along the inner peripheral surface of the annular cover 10, the outer side and the inner side of the curved shape can be defined. The outer side of the curved shape is the side that contacts the inner peripheral surface of the annular cover 10, and the inner side of the curved shape is the opposite side (the side that does not contact the inner peripheral surface of the annular cover 10).

[0046] The belt-like member 21 of this embodiment is composed of a plurality of curved members. Specifically, it is composed of four curved members, namely, a first curved member 21a, a second curved member 21b, a third curved member 21c, and a fourth curved member 21d. Note that the belt-like member 21 may be composed of one curved member, or may be composed of two or three curved members, or may be composed of five or more curved members.

[0047] The first bending member 21a, the second bending member 21b, the third bending member 21c, and the fourth bending member 21d are connected in the circumferential direction to form a single belt-like member 21 having a shape close to a circle. The first bending member 21a and the second bending member 21b are connected at corresponding end portions in the longitudinal direction (circumferential direction) by a first connecting portion 22. The second bending member 21b and the third bending member 21c are connected at corresponding end portions in the longitudinal direction (circumferential direction) by a second connecting portion 23. The third bending member 21c and the fourth bending member 21d are connected at corresponding end portions in the longitudinal direction (circumferential direction) by a third connecting portion 24. That is, the first extension member 20 includes the first connecting portion 22, the second connecting portion 23, and the third connecting portion 24.

[0048] Since the first connecting portion 22, the second connecting portion 23, and the third connecting portion 24 have the same structure, the structure of the first connecting portion 22 will be described below. As shown in FIGS. 6 and 7, the first connecting portion 22 includes a first fixing plate 22a fixed to the first bending member 21a, a second fixing plate 22b fixed to the second bending member 21b, and a fastening member 22c. The first fixing plate 22a extends from the longitudinal end portion of the first bending member 21a toward the inside of the curved shape and also extends in the circumferential direction. A first bending groove 22d is formed in the first fixing plate 22a. The second fixing plate 22b extends from the longitudinal end portion of the second bending member 21b toward the inside of the curved shape and also extends in the circumferential direction. With the end portions of the first bending member 21a and the second bending member 21b abutted against each other, the first fixing plate 22a and the second fixing plate 22b overlap in the thickness direction. A second bending groove 22e is formed in the second fixing plate 22b.

[0049] The fastening member 22c is composed of, for example, a hexagonal bolt and a nut. As shown in FIG. 6, with the end of the first curved member 21a and the end of the second curved member 21b abutted against each other and the first fixing plate 22a and the second fixing plate 22b overlapping in the thickness direction, the axis of the bolt is arranged to pass through the first bending groove 22d and the second bending groove 22e. When a nut is screwed onto the axis of the bolt and tightened in this state, the first fixing plate 22a and the second fixing plate 22b are fastened and relative movement is prevented. The first curved member 21a is provided with an insertion portion 22f into which the end of the second curved member 21b is inserted.

[0050] The structure of the connecting portion is not limited to the structures shown in FIGS. 6 and 7. FIGS. 8 and 9 show a first connecting portion 220 according to Modification 1. The first connecting portion 220 according to Modification 1 includes a first fixing plate 221 fixed to the first curved member 21a, a second fixing plate 222 fixed to the second curved member 21b, and a fastening member 223. The first fixing plate 221 has a first extending plate 221a extending toward the inside of the curved shape of the first curved member 21a. The second fixing plate 222 has a second extending plate 222a extending toward the inside of the curved shape of the second curved member 21b. With the end of the first curved member 21a and the end of the second curved member 21b abutted against each other, the first extending plate 221a and the second extending plate 222a overlap in the thickness direction.

[0051] The fastening member 223 is composed of a bolt 223a and a nut 223b. The bolt 223a is inserted through a bolt insertion hole (not shown) formed in the first extending plate 221a and a bolt insertion hole (not shown) formed in the second extending plate 222a. When the bolt 223a is inserted through both bolt insertion holes and the nut 223b is screwed onto the bolt 223a and tightened, the first extending plate 221a and the second extending plate 222a are fastened and relative movement is prevented. The first curved member 21a is provided with an insertion portion 220f into which the end of the second curved member 21b is inserted.

[0052] FIG. 10 is a diagram showing an example (Modification 2) in which the first extension plate 221a and the second extension plate 222a are fastened using a grip plier 224 instead of the fastening member 223. In this example, the first curved member 21a and the second curved member 21b can be connected without forming bolt insertion holes in the first extension plate 221a and the second extension plate 222a and without using the fastening member 223.

[0053] As shown in FIG. 5, the belt-like member 21 includes a handle 25 that protrudes toward the inside of the curved shape. The handle 25 is provided at the longitudinal middle portions of the first curved member 21a, the second curved member 21b, the third curved member 21c, and the fourth curved member 21d, respectively. The number of handles 25 is not limited to four, and any number can be provided. Further, the handle 25 may be provided as necessary and may be omitted.

[0054] The first extension member 20 includes a diameter change structure 26 that enables the belt-like member 21 to be reduced in diameter and increased in diameter. FIGS. 11 and 12 are perspective views showing the diameter change structure 26. The diameter change structure 26 includes a first block 27, a wing nut 28, and a guide plate portion 29. The first block 27 is fixed inside the end portion on the first curved member 21a side in the longitudinal direction of the belt-like member 21, that is, in the fourth curved member 21d, and is made of a high-rigidity and high-strength steel material or the like. The first block 27 extends in the width direction of the fourth curved member 21d. A screw hole (threaded portion) 27a is formed in the first block 27. The screw hole 27a extends in the longitudinal direction of the first block 27 (the width direction of the belt-like member 21) and opens at one longitudinal end surface of the first block 27.

[0055] The butterfly screw 28 is a member corresponding to the object part of the present invention. As shown in FIG. 12, it has a shaft part 28a extending in the width direction of the belt-like member 21 and a head part 28b integrated with the shaft part 28a. A screw groove is formed on the outer peripheral surface of the shaft part 28a, and the part of the shaft part 28a where the screw groove is formed (the part extending from the axial intermediate part to the base end part) is screwed into the screw hole 27a of the first block 27. In a state where the shaft part 28a is screwed into the screw hole 27a, the tip side part of the shaft part 28a is provided so as to protrude in the width direction from one end part in the width direction on one longitudinal side of the belt-like member 21. A head part 28b is formed at the tip of the shaft part 28a so as to protrude in the radial direction of the shaft part 28a (see FIG. 13).

[0056] The guide plate part 29 is fixed to the other longitudinal side of the belt-like member 21, that is, the end part on the side of the fourth curved member 21d in the first curved member 21a. The guide plate part 29 protrudes from one end part in the width direction of the first curved member 21a toward the inside of the curved shape of the belt-like member 21 and extends in the longitudinal direction of the belt-like member 21. This guide plate part 29 is also made of a high-rigidity and high-strength steel material or the like.

[0057] The guide plate part 29 has a slit 29a into which the shaft part 28a enters. The slit 29a extends in the longitudinal direction of the guide plate part 29 which is the longitudinal direction of the belt-like member 21. The width of the slit 29a is set to be slightly larger than the outer diameter of the shaft part 28a, and the shaft part 28a can easily move in the longitudinal direction within the slit 29a.

[0058] The base end portion 29b of the slit 29a is bent in a direction approaching the inner surface (inner face) of the curved shape in the first curved member 21a. The slit 29a extends continuously from the base end portion 29b to the tip end portion 29c, and a bent portion 29d that bends in a direction approaching the inner surface of the first curved member 21a is formed in a portion closer to the tip end portion 29c. The region from the base end portion 29b of the slit 29a to the bent portion 29d is formed so as to gradually separate from the inner surface of the first curved member 21a as it approaches the bent portion 29d. Then, the bent portion 29d bends in a direction approaching the inner surface of the first curved member 21a, and the tip end portion 29c continuous with the bent portion 29d is open at the edge of the guide plate portion 29. The shaft portion 28a can be inserted into the slit 29a from the tip end portion 29c.

[0059] When the shaft portion 28a enters the slit 29a, a head portion 28b is provided at the tip end portion of the shaft portion 28a as a retaining portion formed wider than the width of the slit 29a, so that the shaft portion 28a cannot come off in the axial direction from the slit 29a. Therefore, the shaft portion 28a is guided in the extending direction of the slit 29a (the longitudinal direction of the belt-like member 21) by the edge of the slit 29a. That is, the slit 29a corresponds to a guiding portion that guides the shaft portion 28a in the longitudinal direction of the belt-like member 21.

[0060] When the wing nut 28 is rotated in the tightening direction with the shaft portion 28a inserted into the slit 29a, the head portion 28b of the wing nut 28 abuts against the edge of the slit 29a in the guide plate portion 29. When the wing nut 28 is further rotated in the tightening direction in this state, the edge of the slit 29a in the guide plate portion 29 is fastened by the head portion 28b and the end face of the first block 27 having the screwed portion 27a, and the relative movement between the guide plate portion 29 and the wing nut 28 is blocked.

[0061] The first extension member 20 is provided on each of one side and the other side in the longitudinal direction of the belt-like member 21, and includes a spacer receiving portion 90 for receiving a spacer 80 (shown in FIGS. 12 and 15) for holding the expanded state of the belt-like member 21. The spacer 80 is also made of a high-rigidity and high-strength steel material or the like.

[0062] The spacer receiving portion 90 includes a first block 27 and a second block 91. The second block 91 is configured in the same manner as the first block 27 and is fixed inside the end portion on the other longitudinal side of the strip member 21, that is, on the side of the fourth bending member 21d in the first bending member 21a.

[0063] A third block 92 is fixed to a portion of the inner surface of the fourth bending member 21d that is longitudinally separated from the first block 27. Further, a fourth block 93 is fixed to a portion of the inner surface of the first bending member 21a that is longitudinally separated from the second block 91. Further, a fifth block 94 is fixed to a portion of the inner surface of the first bending member 21a that is longitudinally separated from the fourth block 93.

[0064] FIGS. 11 and 14 show a state in which the strip member 21 is reduced in diameter, and the shaft portion 28a is caught by the bent portion that has moved to the proximal end portion 29b within the slit 29a. At this time, as shown in FIG. 11, the first block 27 and the fifth block 94 come into contact with each other to serve as a stopper in the diameter-reducing direction. By rotating the wing screw 28 in the tightening direction in this state, the relative movement between the guide plate portion 29 and the wing screw 28 is blocked, so that the strip member 21 is held in a diameter-reduced state. Thereby, it is possible to prevent the strip member 21 from expanding in diameter during conveyance.

[0065] When expanding the strip member 21 in a diameter-reduced state, after loosening the wing screw 28, when a force is applied to the strip member 21 in the diameter-expanding direction, the shaft portion 28a moves within the slit 29a to the distal end portion 29c. In this state, the arms of a hydraulic expander (not shown) are applied to the third block 92 and the fourth block 93 to apply a force in a direction in which the third block 92 and the fourth block 93 move away from each other. Thereby, the strip member 21 can be expanded to press the annular covering body 10 against the inner peripheral surface of the first pipe 101. When a predetermined pressing force is obtained, by installing the spacer 80 between the first block 27 and the second block 91, the expanded state of the strip member 21 is maintained. The second expansion member 30 can also be reduced in diameter and expanded in the same manner.

[0066] (Modification Example 3 of the Connecting Portion) Figures 16 and 17 show Modification Example 3 applied to the connecting portion of the first bending member 21a, the second bending member 21b, the third bending member 21c, and the fourth bending member 21d. Figures 16 and 17 show an example of the first connecting portion 230. The first connecting portion 230 of Modification Example 3 includes a first fixing plate 231 fixed to the first bending member 21a, a second fixing plate 232 fixed to the second bending member 21b, and a toggle clamp 233. A hook 231a for hooking the ring portion 233a of the toggle clamp 233 is fixed to the first fixing plate 231. The toggle clamp 233 is fixed to the second fixing plate 232 and is a well-known device. The first bending member 21a is provided with an insertion portion 230f into which the end portion of the second bending member 21b is inserted.

[0067] In this Modification Example 3, by operating the operation lever 233b of the toggle clamp 233, it is possible to switch between a state where the ring portion 233a is hooked on the hook 231a and a state where it is disengaged from the hook 231a. Therefore, the connection and disconnection of the first bending member 21a, the second bending member 21b, the third bending member 21c, and the fourth bending member 21d can be performed with a simple operation.

[0068] (Function and Effect of the Embodiment) According to this embodiment, after the annular covering 10 is installed so as to extend from the inner peripheral surface of the first pipe 101 to the inner peripheral surface of the second pipe 102, when the belt-like member 21 is disposed inside the annular covering 10 and then expanded and the spacer 80 is received by the spacer receiving portion 90, the belt-like member 21 is held in an expanded state, so that the annular covering 10 is in close contact with the inner peripheral surface of the first pipe 101. Similarly, the annular covering 10 is in close contact with the inner peripheral surface of the second pipe 102 by the second expanding member 30.

[0069] Then, a test fluid is supplied to the space R formed between the outer peripheral surface of the annular covering 10 and the first pipe 101 and the second pipe 102, and by measuring the pressure change of the test fluid, the result of the watertightness test can be obtained.

[0070] Among a plurality of connection parts, after performing the waterproof test on one connection part as described above, when performing the waterproof test on a connection part different from that connection part, it is necessary to reduce the diameter of the belt-like member 21 in the expanded state. At this time, since the shaft part 28a of the belt-like member 21 is guided in the longitudinal direction of the belt-like member 21 by the slit 29a, the work of reducing the diameter of the belt-like member 21 becomes easy. By reducing the diameter of the belt-like member 21, the work of transporting the inside of the pipe to another connection part also becomes easy. When transporting the belt-like member 21, the belt-like member 21 may be rolled, or it may be transported in a suspended state using a cart or the like (not shown).

[0071] After transporting the belt-like member 21 to another connection part and expanding it, when expanding, since the shaft part 28a of the belt-like member 21 is guided in the direction opposite to the diameter-reducing direction by the slit 29a, the work of expanding the diameter of the belt-like member 21 becomes easy.

[0072] Therefore, since all the operations of reducing the diameter of the belt-like member 21, transporting it, and expanding the diameter become easy, even if it is necessary to repeat the waterproof test dozens of times or more than a hundred times, it is possible to significantly reduce the labor.

[0073] The above-described embodiments are merely illustrative in all respects and should not be construed in a limiting sense. Further, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

Industrial Applicability

[0074] As described above, the expansion member of the waterproof test device according to the present invention can be used, for example, when connecting a plurality of pipes on-site to form a water channel or the like.

Explanation of Reference Numerals

[0075] 1 Waterproof test device 10 Annular covering 20 First expansion member 21 Belt-like member 27a Threaded hole (screwed part) 28b Shaft part (guided part) 29 Guide plate part 29a slit (guide part) 80 spacer 90 spacer receiving part

Claims

1. An expansion member of a watertightness test device for pressing an annular covering member of a watertightness test device for testing the watertightness of a connection portion between a first pipe and a second pipe against the inner peripheral surface of the pipe, a strip-shaped member having a curved shape extending along the inner peripheral surface of the annular covering member and composed of a flexible member, a guided portion provided on one side in the longitudinal direction of the strip-shaped member, a guiding portion provided on the other side in the longitudinal direction of the strip-shaped member for guiding the guided portion in the longitudinal direction of the strip-shaped member, and spacer receiving portions provided on one side and the other side in the longitudinal direction of the strip-shaped member respectively for receiving spacers for maintaining the expanded state of the strip-shaped member. The expansion member of the watertightness test device.

2. In the expansion member of the watertightness test device according to Claim 1, the guided portion has a shaft portion extending in the width direction of the strip-shaped member, the guiding portion is composed of a slit extending in the longitudinal direction of the strip-shaped member and into which the shaft portion fits. The expansion member of the watertightness test device.

3. In the expansion member of the watertightness test device according to Claim 2, a plate portion that protrudes toward the inside of the curved shape in the strip-shaped member, extends in the longitudinal direction of the strip-shaped member, and has the slit is provided. The expansion member of the watertightness test device.

4. In the expansion member of the watertightness test device according to Claim 3, the shaft portion is provided so as to protrude in the width direction from one end portion in the width direction on one side in the longitudinal direction of the strip-shaped member, the plate portion protrudes toward the inside of the curved shape from one end portion in the width direction on the other side in the longitudinal direction of the strip-shaped member. The expansion member of the watertightness test device.

5. In the expansion member of the watertightness test device according to Claim 3, a retaining portion formed wider than the width of the slit is provided at the tip of the shaft portion. The expansion member of the watertightness test device.

6. In the expansion member of the watertightness test device according to Claim 5, a screw groove is formed on the outer peripheral surface of the shaft portion, the portion of the shaft portion where the screw groove is formed is screwed into a screwing portion provided on one side in the longitudinal direction of the strip-shaped member, and the edge portion of the slit in the plate portion is fastened by a member having the retaining portion and the screwing portion. The expansion member of the watertightness test device.

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