JP3312864B2 - Piping leak inspection method and inspection tool - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for inspecting leakage of piping, and more particularly to a method of inspecting leakage of new piping made of synthetic resin safely, reliably and efficiently. And an inspection tool.

[0002]

2. Description of the Related Art Conventionally, water pipes have often been made of metal materials such as copper, iron, and lead. However, recently, due to problems of corrosion resistance, workability, and manufacturing cost, vinyl chloride resin is used in place of these metal materials. Such synthetic resins are often used. When using these synthetic resin pipes, a large number of pipes are connected in advance to form a unit, and in the case of piping work on site, these unitized pipes are often used. Such unit piping to which a plurality of pipes are connected is usually inspected at a factory to determine whether the adhesion of the connection is sufficient or to check the leakage of other parts before construction on site. is there. In some cases, leakage inspection of new pipes is performed by actually injecting water into the pipes.However, if water is used, it is difficult to clean up after inspection, so introduce compressed air into the pipes. Often done. Specifically, a cylindrical water stop piece made of an elastic body is inserted into the inner surface of the open end of the pipe, and this water stop piece is compressed and expanded in diameter to make close contact with the inner surface of the pipe. The inspection is performed by introducing compressed air from the end.

[0003]

However, in this method, since the water blocking piece is fixed only by frictional resistance with the pipe, the water blocking piece is fixed by the pressure of the compressed air introduced into the pipe. In some cases, the operator may jump out of the pipe and hit the operator at a high speed, and the leakage inspection is very dangerous for the operator. Also, when water is injected into the pipe, the same danger exists as when compressed air is introduced because the air remaining in the pipe is compressed. In view of such a situation, the pipe is clamped from the outside by sandwiching the pipe from the outside with a fastening jig (A) as shown in FIG. 17, inserting a bolt into the fixing hole (B) and screwing it into a nut. A method of firmly fixing the water stop piece inside the pipe is also adopted. However, this method requires the work of tightening a plurality of bolts to fix the tightening jig (A) to the pipe, and further requires the work of loosening the bolts after the inspection is completed. The work of tightening and loosening the bolts is extremely difficult. This is a troublesome and time-consuming operation, which causes the work efficiency of the leak inspection to be significantly reduced. In addition, even with this method, the water stop piece is fixed only by frictional resistance with the pipe, so if the bolts are insufficiently tightened or the pressure of the compressed air or water, the water stop piece is eventually turned off. It could jump out of the pipes, and it was not a method that could completely avoid the danger of workers.

[0004]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a part of the inner peripheral surface is cut all around the inlet and outlet of a synthetic resin pipe. At least at the pipe end, the missing tubular member is fitted so that the inner peripheral surface is in contact with the outer peripheral surface of the pipe, and the water stop piece made of an elastic body whose diameter can be expanded inside the pipe inlet and outlet is provided. The pipe is inserted at the position corresponding to the cut-out inner surface of the tubular member, and among these water stop pieces, the water stop piece on the entrance side is made water-permeable, and the pipe is deformed and expanded by expanding the diameter of these water stop pieces. And then abutting against the cut-out inner surface of the tubular member, and then inspecting the leakage of the piping by introducing compressed air or water from the water blocking piece on the inlet side. Method and cylindrical shape with through holes drilled along the central axis An elastic body, a threaded rod inserted into the through hole, a receiving plate provided at the distal end of the threaded rod and in contact with the distal end face of the elastic body, and a base end face of the elastic body loosely fitted in a middle portion of the threaded rod. A water-stopper composed of a washer that abuts, a nut screwed adjacent to the washer at the base end than the washer in the middle of the screw rod, and a water-stoppable water-stopper with a hollow screw rod; The present invention solves all of the above problems by providing a pipe leakage inspection tool, which is configured by a water stop piece and a tubular member having a part of an inner peripheral surface cut out over the entire circumference. .

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a pipe leakage inspection method and an inspection tool according to the present invention will be described below with reference to the drawings. 1 to 6 are explanatory views showing a pipe leakage inspection tool according to the present invention. FIG. 1 is an external view of a water stop piece for sealing the pipe, FIG. 2 is a cross-sectional view thereof, and FIG. FIG. 4 to FIG. 6 are cross-sectional views of a possible water stopping piece, and FIG. 4 to FIG. 6 show a tubular member fitted to the inspection pipe.

First, a water stopping piece (1) for sealing a pipe will be described with reference to FIGS. 1 and 2. The water stopping piece (1) includes a cylindrical elastic body (3) having a through hole (2) formed along the central axis, and a screw rod (4) inserted through the through hole (2) of the elastic body (3). ), A receiving plate (5) provided at the distal end of the screw (4) and in contact with the distal end surface of the elastic body (3), and a base end surface of the elastic body (3) loosely fitted in the middle of the screw (4). It comprises a washer (6) to be in contact with, and a nut (7) which is screwed in the middle of the screw rod (4) and closer to the washer at the base end than the washer (6). A right-hand screw (41) and a left-hand screw (42) are formed on the outer peripheral surface of the screw rod (4).

The water-stopper (8) through which water can pass is different from the water-stopper (1) for sealing the pipe in that the screw rod (4) is hollow as shown in FIG. Since the screw (4) is hollow, it is possible to introduce water or compressed air into the pipe in a state where the water stop piece (8) is expanded and fixed inside the pipe, as described later. ing. The external view of the water stop piece (8) through which water can pass is also the same as that of FIG. 1, and the configuration other than that described above is the same as that of the water stop piece (1) for sealing the pipe. The same reference numerals are given to the same members, and the description is omitted.

FIGS. 4 to 6 are cross-sectional views of first to third embodiments of the tubular member fitted to the inspection pipe. The tubular member (9) has a cylindrical shape, and its inner peripheral surface is partially cut out over the entire circumference. Notch surface (9
1) has a tapered shape in the example shown in FIG. 4, has an arcuate cross section in the example shown in FIG. 5, and has a rectangular cross section in the example shown in FIG. The shape of the cutout surface (91) is not limited to the illustrated example, but the length of the cutout surface (91) is as follows.
It is preferable that the length is at least 0.5 to 1 times the length of the elastic body (3) of the sealing water blocking piece (1) for sealing and the water blocking piece (8) capable of passing water. The reason for this is that the length of the cutout surface (91) is set to be equal to the length of the elastic body (3) at the time of leakage inspection described later.
If the length is less than 0.5 times the length of the elastic body, the deformation of the pipe caused by the expansion of the elastic body cannot be sufficiently received by the tubular member (9), so that the fixing strength of the water stopping piece in the pipe is insufficient. On the other hand, when the length of the cutout surface (91) is at least one time the length of the elastic body (3), the outer surface of the pipe and the cutout surface (91) are in a state where the elastic body is completely expanded. This is because a gap may be formed between them, and the fixing strength of the water stopping piece in the pipe becomes insufficient. The inner diameter of the portion where the notched surface (91) is not formed is substantially the same as the outer diameter of the pipe to be inspected. The tubular member (9) does not necessarily have to be constituted by one member, and may be constituted by, for example, combining two members having a semicircular cross section.

FIGS. 7 and 8 are cross-sectional views showing another embodiment of the pipe leakage inspection tool according to the present invention. The embodiment shown in FIG. 7 is an example in which a water-stopper (8) and a tubular member (9) through which water can pass are integrated, and the embodiment shown in FIG. This is an example in which a tubular member (9) is integrated. In this example, the tubular member (9) has a cylindrical shape with a bottom, and a through hole (93) is formed in the bottom (92). Then, the threaded rod (4) of the waterproof block is inserted into the through hole (93), a spacer (10) is interposed between the washer (6) and the nut (7), and the spacer (10) and the nut (7) are used. By sandwiching the bottom (92) of the tubular member, the water blocking piece and the tubular member are integrated. In the embodiments shown in FIGS. 7 and 8, the cylindrical portion of the tubular member (9) may have a tapered shape as shown in FIG. 4 or an arc-shaped cross section as shown in FIG.

[0010] When a pipe is to be inspected for leakage using the leak inspection tool having the above-described configuration, a plurality of synthetic resin pipes made of vinyl chloride or the like are connected as shown in FIG. A cylindrical member (9) is fitted around the outer periphery of the inlet and outlet of the pipe (11), and in this state, a water stop piece (8) capable of passing water to the inlet side and a water stop piece for sealing is provided at the outlet side. Insert (1) respectively. At this time, a portion where the inner peripheral surface of the tubular member (9) is not notched is always located at the pipe end side, and the inner peripheral surface of the tubular member (9) is located at the pipe open end side. It comes into contact with the outer peripheral surface of the pipe (11). Also,
The water stopping pieces (1) and (8) are fixed at positions such that the elastic body (3) corresponds to the cutout surface (91) of the tubular member (9) as shown in the figure. In this specification, the expression of the inlet and outlet of the pipe is an opening for introducing water or compressed air for leakage inspection as an inlet, and other openings as outlets for convenience. It does not mean an inlet and an outlet when the fluid actually flows.

[0011] As shown in FIG. 9, with the water stop pieces (1) and (8) inserted into the pipe (11), the water stop pieces (1) and (8) are next inserted.
(8) The diameter is increased. The diameter expansion of the water stop pieces (1) and (8)
As shown in FIG. 10, the inner cylinder (12a) and the outer cylinder (12b)
This is performed by using an operating rod (12) composed of: Specifically, an outer cylinder (12b) having a nut screwdriver formed on the inner surface of the distal end is fitted to the nut (7) of the water stop piece, and a female screw formed on the inner surface of the distal end of the inner cylinder (12a) is screwed into the screw (4). )
The elastic body (3) is screwed with the left screw (42) carved at the end of the inner cylinder (12a) and the inner cylinder (12a) is rotated while the outer cylinder (12b) is fixed. ) And the washer (6) to compress and expand in the outer diameter direction.

FIG. 11 is a view showing a state in which all the water stopping pieces (1) and (8) are expanded in diameter. The pipe (11) made of a synthetic resin material is deformed and expanded by expanding the diameter of the water blocking pieces (1) and (8), and the cutout surface (9) of the tubular member (5) is cut.
Contact 1). In this state, a pressure gauge, a valve, or the like is appropriately connected to the threaded rod (4) of the water stop piece (8) through which water can flow, and compressed air or water is introduced into the pipe. At this time, as shown in the figure, the water blocking pieces (1) and (8) are fitted outwardly in the cutout surface (91) of the tubular member (5) through deformation of the pipe (11), that is, the pipe opening. Since the movement toward the end is regulated, the pipe (1) is compressed by the pressure of the introduced compressed air or the air compressed by the introduction of water.
Does not jump out of 1).

In the illustrated example, an example is shown in which cylindrical members (5) of different shapes are all fitted on the respective open ends (inlet and outlet), but cylindrical members (5) of the same shape are all present.
Needless to say, it may be used. Further, in the illustrated example, an example in which a T-shaped pipe is inspected is shown, but the pipe to be inspected in the present invention is not particularly limited in shape or length.

FIG. 12 and FIG. 13 are explanatory views showing a leak inspection method when an inspection tool in which a water stop piece and a tubular member are integrated is used. In this method, the tubular member (9)
Is fitted until the bottom portion (92) comes into contact with the open end face of the pipe (11) (see FIG. 12). In this state, the diameter is expanded by compressing the elastic body (3) by the method described above, and the pipe (11) is expanded. The pipe is deformed and expanded to abut on the cutout surface (91) of the tubular member (5) (see FIG. 13). Introduce water. According to this method, since the positional relationship between the water stop piece and the cutout surface of the tubular member is predetermined, it is not necessary to adjust the insertion position of the water stop piece at the time of work, and the workability is excellent. .

In the present invention, the water stop piece (1),
As (8), it is more preferable to use a water stop piece in which the outer surface of the elastic body (3) is covered with a net material (13) as shown in FIGS. Note that FIG.
16 is a sectional view taken along line AA of FIG. 15, and FIG. 16 is a sectional view taken along line BB of FIG. More specifically, the structure of the water stopping piece will be described. A plurality of mesh members (13) (three in the illustrated example, but may be four or more) are arranged at a fixed interval on the outer peripheral surface of the elastic body (3). The mesh members (13) are spaced apart from each other.
a) is folded and embedded in the elastic body (3) at a position about one third of the entire length from the distal end of the elastic body (3), and has a proximal end portion (13).
b) is bent and elastically fixed between the base end surface (3a) of the elastic body (3) and the washer (6). Since other structures of the water stop piece are substantially the same as those of the water stop pieces (1) and (8), the same members are denoted by the same reference numerals and description thereof will be omitted.

In the above construction, the reason why the net material (13) is not covered over the entire circumference of the elastic body (3) is that the net material (13)
Is covered over the entire circumference, the elastic body (3) is less likely to expand and expand in diameter. The reason why the mesh material (13) is not covered up to the tip of the elastic body (3) is that the mesh material (13) is 3)
When the elastic material (3) expands when covered to the tip of
This is because the tip of the net (13) may be broken by the propulsive force applied to the tip of (3).

In the case where a water stop piece covered with a net material as shown in FIGS. 14 to 16 is used, when the elastic body (3) expands, the net material (13) gets into the inner surface of the pipe (11) and stops. The frictional resistance between the water piece and the pipe increases, and the risk of the water piece flying out during leakage inspection can be further reduced.

[0018]

As described above, according to the present invention, a cylindrical member having a part of the inner peripheral surface cut out over the entire circumference is provided on the outer periphery of the inlet and outlet of the synthetic resin pipe at least at the pipe end. On the side of the pipe, the inner peripheral surface is fitted so as to be in contact with the outer peripheral surface of the pipe, and the water stop piece made of an elastic body that can be expanded inside the inlet and outlet of the pipe corresponds to the cut-out inner surface of the tubular member. In addition to this, the water stop pieces on the inlet side among these water stop pieces are made water-permeable, and the pipes are deformed and expanded by expanding the diameter of the water stop pieces, thereby cutting off the cylindrical member. After contacting the inner surface, the pipe is inspected for leakage by introducing compressed air or water from the water blocking piece on the inlet side, and the pipe leakage inspection method is characterized by a through hole along the central axis. A cylindrical elastic body with a hole, and a screw rod inserted through the through hole. A receiving plate provided at the distal end of the screw rod and abutting against the distal end surface of the elastic body; a washer loosely fitted in the middle part of the screw rod and abutting on the base end surface of the elastic body; A water stop piece consisting of a nut threaded adjacent to a washer at the base end, a water stop piece having a hollow threaded rod, and a part of the inner peripheral surface extending all around. The pipe leakage inspection device is characterized by being composed of a tubular member cut out over the length of the pipe, so that the water stop piece jumps out of the pipe due to compressed air or water introduced into the pipe at the time of leak inspection. It is possible to prevent the danger of injuring the worker, and to provide an excellent effect that the leak inspection operation can be performed safely, reliably and efficiently.

[Brief description of the drawings]

FIG. 1 is an external view of a water blocking piece for sealing a pipe.

FIG. 2 is a sectional view of FIG.

FIG. 3 is a cross-sectional view of a water stopping piece capable of passing water.

FIG. 4 is a sectional view showing a first embodiment of the tubular member.

FIG. 5 is a sectional view showing a second embodiment of the tubular member.

FIG. 6 is a sectional view showing a third embodiment of the tubular member.

FIG. 7 is a cross-sectional view showing another embodiment of the pipe leakage inspection tool according to the present invention.

FIG. 8 is a cross-sectional view showing another embodiment of the pipe leakage inspection tool according to the present invention.

FIG. 9 is an explanatory diagram of a leak inspection method according to the present invention.

FIG. 10 is an explanatory diagram of a leakage inspection method according to the present invention.

FIG. 11 is an explanatory diagram of a leakage inspection method according to the present invention.

FIG. 12 is an explanatory diagram of another example of the leak inspection method according to the present invention.

FIG. 13 is an explanatory diagram of another example of the leak inspection method according to the present invention.

FIG. 14 is a view showing another embodiment of a water stop piece.

FIG. 15 is a sectional view taken along line AA of FIG. 14;

FIG. 16 is a sectional view taken along line BB of FIG. 15;

FIG. 17 is a diagram showing a fastening jig used for a conventional leak inspection.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Water-stopper for sealing 2 Through-hole 3 Elastic body 4 Screw rod 5 Receiving plate 6 Washer 7 Nut 8 Water-stopper which can pass water 9 Cylindrical member 91 Notch surface 92 Bottom part 93 Through-hole 10 Spacer 11 Pipe 13 Net material

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-136591 (JP, A) JP-A-2-173496 (JP, A) JP-A-1-279196 (JP, A) 90494 (JP, U) Japanese Utility Model Hei 1-82394 (JP, U) Table 6-505552 (JP, A) (58) Fields surveyed (Int. Cl. ⁷ , DB name) F16L 55/00 F16L 55 / 12 F17D 5/02

Claims (4)

(57) [Claims] 1. A cylindrical member having a part of an inner peripheral surface cut out over the entire outer periphery of an inlet and an outlet of a synthetic resin pipe, and an inner peripheral surface having a pipe outer peripheral surface at least at a pipe end side. And a water stop piece made of an elastic body whose diameter can be expanded inside the inlet and outlet of the pipe is inserted into a position corresponding to the cut-out inner surface of the tubular member. Of the pieces, the water stop pieces on the entrance side are made water-permeable, and by expanding the diameter of these water stop pieces, the pipe is deformed and expanded to contact the cut-out inner surface of the tubular member, and then the inlet side A method for inspecting a pipe for leakage by introducing compressed air or water from a water stop piece. 2. A cylindrical elastic body having a through-hole formed along a central axis, a screw inserted through the through-hole, and a distal end surface of the elastic body provided at a tip of the screw. A receiving plate, a washer that is loosely fitted in a middle portion of the screw rod and abuts against a base end surface of the elastic body, and a nut that is screwed into the middle portion of the screw rod so as to be closer to the base end portion than the washer and to the washer. A water stop piece consisting of: a water stop piece capable of passing water with a hollow screw rod of the water stop piece, and a tubular member having a part of the inner peripheral surface cut out over the entire circumference. Characteristic pipe leakage inspection tool. 3. The cylindrical member is formed in a bottomed cylindrical shape having a through hole formed in a bottom portion. The screw is inserted into the through hole, and a spacer is interposed between the washer and the nut. 3. The leak inspection tool for piping according to claim 2, wherein the water stop piece and the tubular member are integrated by sandwiching the bottom of the tubular member with the spacer and the nut. 4. The pipe leakage inspection tool according to claim 2, wherein an outer surface of the elastic body of the water stopping piece is covered with a net material.