JPH0220658Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to a sealing jig for inspecting pipes, etc., and more specifically, for leakage inspection of the pipes themselves, or for joining pipes by welding or joints. This case relates to an inspection sealing jig used for leakage inspection of pipes and their joints.

(Prior art) Generally, when performing a leak test on manufactured pipes, etc., pressure fluid is injected into the pipe, the openings at both ends of the pipe are sealed, and after a predetermined period of time, the pressure state of the pressure fluid is measured using a meter. The presence or absence of leakage is checked by checking the leakage.

By the way, in order to seal the openings at both ends of a pipe, conventionally, as shown in FIG.
0 to the open end surface of the tube 110 by welding 101 to close the opening 111 of the tube 110, or by preparing a jig shaft 105 having a disk-shaped flange 105a at the tip. A ring-shaped rubber gasket 1 is formed by the flange 105a of the jig shaft 105 and the nut 106 screwed onto the end of the jig shaft 105.
07 is clamped through the retainer 108, and the opening 111 of the tube 110 is closed by the gasket 107 bulging and closing against the inner circumferential surface 110a of the tube due to this clamping pressure.

However, in the case of the former case where the iron plate 100 is used to close the pipe, the opening 111 of the pipe 110 must be welded 101 so that it is completely sealed, which requires time and advanced technology, and furthermore, once welded, the closed pipe 110 cannot be reused, and it cannot be applied to pipes that cannot be welded, such as polyethylene pipes. In the latter case where the gasket 107 is used to close the tube, although it does not have the disadvantages of the former, it is held in place only by the friction of the gasket 107 against the inner circumferential surface 110a of the tube, so a large internal pressure is generated inside the tube 110. If the jig shaft 105 and gasket 10
7. There was a possibility that the retainer 108 etc. could slip out, which was extremely dangerous.

(Purpose of the invention) The present invention was devised in view of the above circumstances, and its purpose is to develop a pipe etc. that does not have the former disadvantages and can effectively avoid the latter dangers. The purpose of the present invention is to provide a sealing jig for inspection.

(Structure of the invention) In order to achieve the above-mentioned purpose, the sealing jig for inspecting pipes, etc. according to the invention has a generally disc-shaped flange disposed at the tip of the rod-shaped shaft on the inner peripheral surface side of the pipe end. a jig shaft, which is provided with a threaded portion on the outer circumferential surface of the shaft extending toward the opening surface of the pipe, and further has a fluid press-in passage provided in the flange and the axial center of the shaft; and the flange. a ring-shaped rubber gasket located on the back side of the gasket and interposed between the outer circumferential surface of the shaft portion and the inner circumferential surface of the tube;
At the rear part, there is a ring-shaped first pressing body formed with a tapered surface that gradually slopes downward toward the opening side of the tube; a retaining member having an inclined surface along the tapered surface of the pipe, and a recessed part formed on the outer surface thereof to be recessed into the inner circumferential surface of the pipe; a second pressing member disposed on the back side of the retaining member; The second pressing body, the retaining member, the first pressing body, and the gasket are pressed between the second pressing body, the retaining member, the first pressing body, and the gasket by screwing into the threaded portion of the shaft portion and threading the threaded portion. It is equipped with a nut.

(Example) An example of the present invention will be described below with reference to FIGS. 1 and 2.

In FIG. 1, reference numeral 1 denotes a pipe, and in addition to the metal pipe shown in the figure, suitable pipes such as resin-coated metal pipes or polyethylene pipes are the objects of inspection or testing. 2 is a metal jig shaft,
A generally disc-shaped flange 2b is integrally provided at the tip of the rod-shaped shaft 2a to be placed on the inner peripheral surface 1a side of the tube end, and the outer periphery of the shaft 2a is extended toward the opening surface 1b of the tube 1. A threaded portion 2c is engraved on the surface. Furthermore, a fluid press-in passage 2d communicating with the inside of the tube 1 is bored in the axial center of the collar portion 2b and the shaft portion 2a.
Note that the rear end side of this fluid press-fitting passage 2d has a threaded portion 2.
d' is carved therein, and the pipe 4 for pressure fluid injection with the valve 5 attached thereto is screwed. It may be screwed onto the outer circumferential threaded portion 2c. Further, the back side of the collar portion 2b is connected to the opening surface 1b of the tube 1.
A tapered surface 2b' is formed which gradually slopes diagonally downward.

3 is a ring-shaped or split ring-shaped rubber gasket located on the tapered surface 2b' of the flange 2b. Both sides of this gasket 3 are formed into tapered surfaces 3a, 3a along the tapered surface 2b of the flange 2b, and one of the tapered surfaces 3a is positioned on the tapered surface 2b' of the flange 2b. There is.

Reference numeral 4 designates a ring-shaped first pressing body made of metal, which has a tapered surface 4a formed along the entire circumference on the front surface along the other tapered surface 3a of the gasket 3, and an annular notch step on the rear surface. A tapered surface 4c that gradually slopes downward toward the opening surface 1b of the tube 1 is formed on the outer periphery of the bottom surface of the stepped notched portion 4b. Note that the notch step portion 4b and the second tapered surface 4c of the first pressing body 4 are not limited to being formed in an annular shape, and may be formed in plural numbers in the circumferential direction, for example.

Reference numeral 5 denotes a cut-off ring-shaped metal slip-out prevention member disposed on the tapered surface 4c of the first pressing body 4. This retaining member 5 has a tapered surface 5a formed on its inner circumferential surface along the tapered surface 4c of the first pressing body 4, and has a sharp groove on its outer circumferential surface that is cut into the inner circumferential surface 1a of the tube 1. A plurality of recessed portions 5b are formed. In addition, in the case where a plurality of cutout steps of the first pressing body 4 are formed not in an annular shape but in a circumferential direction, a single piece-shaped retaining member is disposed at each of the cutout step portions. .

Reference numeral 6 denotes a ring-shaped or split ring-shaped metal second pressing body disposed on the back side of the retaining member 5.

7 is screwed into the threaded portion 2c of the jig shaft 2, and by threading the threaded portion 2c toward the flange 2b, the second pressing body 6, This is a nut that sequentially presses the retaining member 5, the first pressing body 4, and the gasket 3.

The sealing jig having the above configuration is arranged in the state shown in FIG. 1. In this case, when the nut 7 is screwed toward the flange 2b from the state shown in FIG. The body 6 and the retaining member 5 are pressed and moved, and the retaining member 5 is pressed against the tapered surface 4c of the first pressing member 4.
It approaches the inner circumferential surface 1a of the tube 1 along. At the same time, the first pressing body 4 is also pressed and moved by the frictional resistance of the retaining member 5 against the first pressing body 4, and the gasket 3 is compressed by the first pressing body 4 and the flange 2b. The convex outer peripheral surface 3b is the pipe 1
approaches or comes into contact with the inner circumferential surface 1a of the Then, when the nut 7 is further tightened toward the flange 2b, the second
As shown in the figure, the retaining part 5b of the retaining member 5 bites into the inner circumferential surface 1a of the tube 1, and the gasket 3 is strongly pressed by the first pressing body 4 and the collar part 2b to form a convex outer circumference. The entire inner circumferential surface 1a of the tube 1 is tightly contacted so that the entire surface 3b is flat.

Therefore, even if the pressure fluid is introduced into the tube 1 through the pressure fluid passage 2d and the internal pressure within the tube 1 becomes a certain level of high pressure, the retaining portion 5b of the retaining member 5 will not flow into the inner circumferential surface of the tube 1. 1a, and the convex outer circumferential surface 3b of the gasket 3 is in strong frictional engagement with the inner circumferential surface 1a of the tube 1. There is no danger that the stopper member 5, second pressing member 6, etc. will slip out. Therefore, leakage inspection of pipes, etc. can be carried out safely.

The tightening force of the nut 7 can be determined by using a torque measuring device so that the sealing performance of the gasket 3 and the retaining force of the retaining member 5 can always be maintained constant.

(Effect of the invention) As described above, according to the inspection sealing jig of the present invention, if the nut is screwed toward the flange while being set inside the pipe end, the second pressing body and the retaining member ,
The first pressing body and the gasket are pressed one after another, and the gasket is brought into close contact with the inner circumferential surface of the pipe by the clamping pressure between the jig shaft flange and the first pressing body, and the retaining member is attached to the tapered surface at the rear of the first pressing body. After moving along the tube toward the inner circumferential surface of the tube, the retaining portion can be bitten into the inner circumferential surface of the tube. Therefore, it is possible to completely seal the inside of the pipe by bringing the gasket into close contact with the inner circumferential surface of the pipe, and furthermore, the frictional engagement of the gasket with the inner circumferential surface of the pipe and the sealing of the retaining part of the retaining member on the inner circumference of the pipe can be achieved. By biting into the surface, the sealing jig will not come out even if the pressure inside the pipe becomes high, allowing safe leakage inspection of pipes, etc.

Moreover, with this type of inspection sealing jig, the required sealing performance and retaining force can be ensured simply by screwing the nut (tightening operation), so there is no need for the difficult welding techniques used in the past. Anyone can easily perform the test, and the pipes to be inspected must be metal pipes, resin-coated steel pipes, or resin-coated steel pipes.
Various types of pipes such as polyethylene pipes can be inspected.

[Brief explanation of the drawing]

Fig. 1 shows an embodiment of the present invention, and is a vertical cross-sectional view of the main part showing the state in which the sealing jig is placed inside the pipe end, and Fig. 2 shows a nut being screwed toward the flange of the jig shaft. A longitudinal cross-sectional view of a main part of the same embodiment showing a state in which it is fed, and FIGS. 3 and 4 are partial longitudinal cross-sectional views showing conventional examples, respectively. DESCRIPTION OF SYMBOLS 1... Pipe, 1a... Inner peripheral surface of the tube, 1b... Opening surface of the tube, 2... Jig shaft, 2a... Shaft part, 2b... Collar part, 2c
... Threaded portion, 2d... Fluid press-in passage, 3... Gasket, 4... First pressing body, 4c... Tapered surface of first pressing body, 5... Retaining member, 5a... Tapered surface of retaining member, 5b... Retaining portion , 6...second pressing body, 7...nut.

Claims (1)

[Claims for Utility Model Registration] A generally disc-shaped flange is provided at the tip of the rod-shaped shaft to be placed on the inner peripheral surface of the tube end, and at the same time, on the outer peripheral surface of the shaft that extends toward the opening surface of the tube. Engraving the threaded part,
Furthermore, a jig shaft having a fluid press-in passage provided in the axial center of the collar and the shaft, and a jig shaft located on the back side of the collar and interposed between the outer circumferential surface of the shaft and the inner circumferential surface of the tube. a ring-shaped rubber gasket located on the back side of this gasket,
At the rear part, there is a ring-shaped first pressing body formed with a tapered surface that gradually slopes downward toward the opening side of the tube; a retaining member having an inclined surface along the tapered surface of the pipe, and a recessed part formed on the outer surface thereof to be recessed into the inner circumferential surface of the pipe; a second pressing member disposed on the back side of the retaining member; The second pressing body, the retaining member, the first pressing body, and the gasket are pressed between the second pressing body, the retaining member, the first pressing body, and the gasket by screwing into the threaded portion of the shaft portion and threading the threaded portion. A sealing jig for inspecting pipes, etc., characterized by being equipped with a nut.