JPH10267900A - Method for inspecting interface peeling of polymer insulator tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inspect a peeling over the entire interface, in non-destructive manner. SOLUTION: In this method, an interface peeling inspection is performed with a polymer insulator tube 1 comprising an FRO tube, a jacket rubber 3 comprising an umbrella part and a barrel part provided on the outside periphery of the FRP tube, and brackets 4-1 and 4-2 provided at both end parts of the FRP tube. The polymer insulator tube 1 and a ultrasonic probe 14 are submerged in water, and an ultrasonic wave is emitted from the jacket rubber 3 side to the polymer insulator tube 1 by the ultrasonic wave prove 14, and its reflected wave is obtained, and based on the reflected wave, a peeling at an interface is inspected. Or, a continuous water flow is supplied into a tube-like body provided with an ultrasonic wave prove in its inside, and while the water flowing out of the end part of tube-like body contacts the barrel part of jacket rubber or bracket at always, an ultrasonic wave is emitted from the ultrasonic wave prove to the bracket or the barrel part of jacket rubber, to obtain the reflected wave of the emitted ultrasonic wave, and based on the reflected wave, peeling at an interface may be inspected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a FRP cylinder, a jacket rubber provided on an outer peripheral surface of the FRP cylinder, comprising a cap portion and a body portion, and metal fittings provided at both ends of the FRP cylinder. The present invention relates to a method for non-destructively inspecting the interface peeling of a polymer insulator tube at an interface between members of a metal fitting, an FRP cylinder, and a jacket rubber or an interface of a joint portion between the members.

[0002]

2. Description of the Related Art Conventionally, in polymer porcelain tubes, it is important for the characteristics of the polymer porcelain tube to prevent separation at the interface between the metal fitting, the FRP cylinder, and the outer rubber, or at the interface between the joints between the members. Are known. FIG. 8 is a diagram for explaining the bonding interface in the polymer insulator tube. FIG.
In the example shown in FIG.
And an outer rubber 53 provided on the outer peripheral surface of the FRP cylinder 52.
And metal fittings 54-1 and 54 provided at both ends of the FRP cylinder 52.
-2. In addition, the outer cover rubber 53
The RP cylinder 52 includes an outer shell 53a provided on the outer peripheral surface and a plurality of caps 53b protruding from the outer shell 53a.

In the above-mentioned polymer insulator 51, the interface which is the object of the present invention is the interface (A) between the outer cylinder 53a of the outer rubber 53 and the FRP cylinder 52, and the outer rubber 53 and the metal fitting 54.
-1 or 54-2 (B), the joint interface between the outer rubber 53 and the outer rubber 53 (C), and the joint interface between the FRP cylinder 52 and the metal fitting 54-1 or 54-2 (D). It is.

The bonding interface (A) between the outer shell 53a of the outer rubber 53 and the FRP cylinder 52 is extremely important for electrical insulation, and this area near the inner shield when a bushing structure is used. Are exposed to a high electric field. Therefore, if the interface (A) is peeled, there is a possibility that a dangerous situation such as a decrease in insulation may occur due to moisture absorption due to rubber permeation moisture or the like. The outer rubber 53 and the metal fittings 54-1 or 54-2 are also provided.
(B) and the interface (C) of the joint between the outer rubber 53 and the outer rubber 53 are entrances of moisture into the interface (A). Further, the FRP cylinder 52 and the metal fittings 54-1 or 54
The bonding interface (D) with -2 affects mechanical strength, particularly bending fracture strength, when insufficient resin filling or non-adhesion occurs at the interface.

[0005]

Therefore, it is necessary to detect the peeling at the interfaces A to D by inspection. Conventionally, in order to discover peeling at the interface (A) between the jacket rubber 53 and the FRP cylinder 52, a visual inspection for confirming swelling and the like, and an abnormality such as dielectric breakdown due to application of electricity between the metal fittings 54-1 and 54-2. A withstand voltage test for confirming the test and a peeling test for performing a sampling destruction inspection are performed. However, fine peeling cannot be found by visual inspection, it is almost impossible to detect it in a dry state in a withstand voltage test, and non-destructive inspection is not possible in a peeling test and it is difficult to conduct a full inspection There was a problem.

Further, in order to discover separation at the joint interface (D) between the FRP cylinder 52 and the metal fittings 54-1 or 54-2, an internal pressure test for applying stress to the joint by water pressure,
An airtightness test is performed in which the inside is filled with F6 gas and airtight leakage (leakage) from a joint is confirmed. However, in the internal pressure test, since the applied stress is lower than the fracture stress, the stress is not perfect, and in the airtightness test, there is a problem that the filling state of the entire interface cannot be grasped. Therefore, development of a test method capable of non-destructively examining peeling at the entire interface has been desired.

An object of the present invention is to solve the above-mentioned problems,
It is an object of the present invention to provide a method for inspecting interfacial peeling of a polymer porcelain tube, which can inspect non-destructive peeling at the entire interface.

[0008]

The first invention of the method for inspecting interfacial peeling of a polymer porcelain tube according to the present invention comprises an FRP cylinder and an FR tube.
In a method for inspecting interfacial peeling of a polymer porcelain tube comprising a jacket rubber formed of a cap portion and a body portion provided on an outer peripheral surface of a P cylinder and metal fittings provided on both ends of an FRP cylinder, a polymer porcelain tube and an ultrasonic probe are used. And immersing them in water, irradiating ultrasonic waves to the polymer porcelain tube from the outer rubber side with an ultrasonic probe, finding the reflected waves, and inspecting the interface for separation based on the obtained reflected waves. It is.

A second invention of the method for inspecting interfacial peeling of a polymer porcelain tube according to the present invention comprises a FRP cylinder, a jacket rubber comprising a cap and a body provided on the outer peripheral surface of the FRP cylinder, In the method for inspecting interface delamination of a polymer porcelain tube composed of metal fittings provided at both ends, a water flow is continuously supplied to a cylindrical body having an ultrasonic probe therein, and water flowing out from an end of the cylindrical body is always supplied. Ultrasonic waves are radiated from the ultrasonic probe to the bracket or the body of the rubber jacket while in contact with the body of the bracket or the rubber jacket, and the reflected wave of the irradiated ultrasonic wave is obtained. Inspection of the interface between the body of the jacket rubber and the FRP cylinder, the interface between the jacket rubber and the metal fittings, the interface at the joint between the jacket rubber and the coating rubber, or the interface between the FRP cylinder and the metal fittings It is characterized by the following.

According to the present invention, ultrasonic waves are sequentially applied to the surface of the shell of the rubber sheath of the polymer insulator and the surface of the metal fitting, and the reflected waves are obtained. The interface is separated based on the obtained reflected waves, preferably the phase of the reflected waves. It has been found that it can be suitably inspected.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a view for explaining a first invention in a method for inspecting interfacial peeling of a polymer insulator according to the present invention. The polymer insulator 1 has the same configuration as the conventional polymer insulator 51 shown in FIG.
(Not shown) on the outer periphery of the outer cover rubber 3 and the metal fittings 4-1 and 4-2.
Is provided. In the example shown in FIG.
Is a water tank, 12-1 and 12-2 are rotating devices for holding the metal fittings 4-1 and 4-2 and rotating the polymer porcelain tube 1,
Reference numerals 13-1 and 13-2 denote lateral displacement prevention devices provided in the rotation devices 12-1 and 12-2, respectively, and reference numeral 14 denotes a rotation device 12-.
Ultrasonic probes 15-1 and 15-2, which are movable between 1 and 12-2 and are connected to an ultrasonic flaw detector (not shown).
Is a lid for closing the metal fittings 4-1 and 4-2. In addition, the ultrasonic probe 14 and the rotation devices 12-1 and 12-2 are configured to be movable in the vertical direction.

In the apparatus having the structure shown in FIG. 1, the interfacial peeling inspection of the present invention is carried out as follows. First, the lids 15-1 and 15-1 are attached to the metal fittings 4-1 and 4-2 of the polymer insulator tube 1, respectively.
-2 is provided, and in this state, the metal fittings 4-1 and 4-2 are mounted on the rotating devices 12-1 and 12-2. Here, by controlling the water level in the water tank 11 and changing the volume of the submerged portion of the polymer porcelain tube 1 to adjust the buoyancy, the weight of the polymer porcelain tube 1 applied to the rotating devices 12-1 and 12-2 is kept constant. The rotation device 12
-1, 12-2 can be reduced. Then, the polymer insulator 1 is rotated about its central axis by the rotating devices 12-1 and 12-2. In this state, the ultrasonic probe 1
4 is moved from the metal fittings 4-1 to 4-2, and ultrasonic waves are transmitted from the ultrasonic probe 14 to the metal fittings 4 via water.
At the same time as irradiating the surface of -1, 4-2 and the surface of the jacket rubber 3, the reflected wave is received as an echo. At this time, if the polymer insulator tube 1 has a tapered shape, it is driven up and down in accordance with the shape. By analyzing the received echo with an ultrasonic flaw detector, it is possible to determine whether or not the interface has peeled off. In addition, since the portion of the cap 3b on the surface of the outer cover rubber 3 has a large rubber thickness, there is much noise, and it is difficult to determine the presence or absence of interfacial peeling at the portion corresponding to the cap 3b.
Is performed only in the portion corresponding to.

Here, the determination of the separation of the interface can be performed as follows. That is, FIG. 2 (a),
The trunk 3a of the jacket rubber 3 of the normal product shown in FIG.
The waveform of the echo at the interface with the core 2 and FIGS. 3 (a) and 3 (b)
The defective portion 21 consisting of the air layer shown in FIG.
As can be seen by comparing the waveform of the echo of the peeled product existing at the interface with the P core 2, the phase of the waveform at the defect portion 21 at the interface of the peeled product is inverted as compared with the phase at the interface of the normal product. ing. That is, when an ultrasonic wave passes from a material having a large impedance to a material having a small impedance due to a change in a member, the phase thereof is inverted. Here, in a normal product, there is no difference between the impedance of the jacket rubber 3 and the FRP core 2, whereas the impedance of the jacket rubber 3 and the defective portion 21 having the air layer has a larger impedance. Therefore, it is considered that the phase inversion phenomenon occurs. The phase inversion phenomenon in the waveform of the echo described above is caused by the bracket 4-1 and the bracket 4-1.
The same applies to the interface between the 4-2 and the FRP core 2, the interface between the metal fittings 4-1 and 4-2 and the outer rubber 3, and the joint interface between the outer rubber 3 and the outer rubber 3. The detection of the peeled portion by the method can be carried out at all the interfaces targeted by the present invention.

FIGS. 4 (a) and 4 (b) are diagrams for explaining another example of the method for inspecting interface peeling of a polymer porcelain tube according to the present invention. The difference from the example shown in FIG. 1 is that the example shown in FIG. 1 shows an example in which lids 15-1 and 15-2 are provided at both ends of the polymer porcelain tube 1 and the inspection is performed in a state where the water immersion level is controlled. On the other hand, FIG. 4A shows an example in which the polymer insulator 1 is immersed in water without covering both ends of the polymer insulator 1, and the ultrasonic probe 14 is moved along the water surface to perform the inspection.
In FIG. 4B, lids 15-1 are provided at both ends of the polymer insulator 1.
15-2 is an example in which the rotating devices 12-1 and 12-2 are pressed against and held by the polymer insulator 1 floating by buoyancy, and the entire polymer insulator 1 is submerged in water to perform an inspection. . In any of the examples, the ultrasonic probe 14 and the body 3a of the outer rubber 3 or the metal fittings 4-1 and 4-2 are used.
Since water exists as a medium for transmitting ultrasonic waves between the first and second embodiments, the interface peeling inspection of the present invention can be performed in the same manner as in the example of FIG. However, as shown in FIG. 4A, when the entire polymer insulator tube 1 is submerged, moisture is absorbed from the inner surface of the FRP core 2 and a drying step is required. Also, as shown in FIG. 4B, lids 15-1 and 15
When the inspection is performed with the entire body submerged under -2, a lift is required because the body is lifted by buoyancy. for that reason,
In conducting the inspection, it is necessary to conduct the inspection based on the above characteristics.

FIG. 5 is a diagram showing the configuration of another example of the inspection apparatus shown in FIG. In the example shown in FIG. 1, when the polymer porcelain tube 1 is rotating with a part of the polymer porcelain tube 1 going out of the water, air bubbles easily adhere to the surface of the jacket rubber 3 and a detection error occurs. There is. Therefore, in the example shown in FIG. 5, an attached bubble removing device including a submersible pump 22 and a nozzle 23 for removing bubbles is provided integrally with the ultrasonic probe 14 so that the ultrasonic probe 14 can emit ultrasonic waves. Prior to this, water in the water tank 11 is jetted from the nozzle 23 to the portion to be irradiated with the ultrasonic wave by driving the submersible pump 22 to remove bubbles.

FIG. 6 is a view for explaining the second invention in the method for inspecting interface peeling of a polymer insulator according to the present invention. In the example shown in FIG. 6, the water in the water tank 33 can be continuously supplied from the lower side of the cylindrical body 31 having the ultrasonic probe 14 therein by the pump 32 with the deaeration function. 34-1 and 34-2 are guide rollers for allowing the tip 31a of the tubular body 31 to move with respect to the polymer porcelain tube 1 while keeping a constant interval with respect to the surface of the outer cover rubber 3. It is. Reference numeral 35 denotes an ultrasonic flaw detector connected to the ultrasonic probe 14.

An interface peeling inspection method in the example shown in FIG. 6 will be described with reference to FIG. In the example shown in FIG.
A water flow is continuously supplied from the tip 31a of the cylindrical body 31 which is kept at a fixed distance from the outer shell 3a of the outer rubber 3 in the polymer insulator tube 1, and the water flowing out from the tip 31a of the cylindrical body 31 is constantly discharged. The rubber 3 is brought into contact with the outer cylinder 3a.
In this state, the cylindrical body 31 is moved in the circumferential direction with respect to the polymer porcelain tube, and at the same time, the ultrasonic probe 14 irradiates the ultrasonic wave to the outer casing 3a to obtain an echo which is a reflected wave of the irradiated ultrasonic wave. . Then, based on the obtained reflected wave, preferably based on the phase of the waveform of the obtained reflected wave, by inspecting the interface separation in the same manner as in the above-described example, the interface separation inspection of the polymer insulator can be performed.

[0018]

As is apparent from the above description, according to the present invention, ultrasonic waves are sequentially radiated on the surface of the body of the rubber sheath of the polymer insulator and the surface of the metal fitting, and the reflected waves are obtained. Since the separation at the interface is inspected based on the phase of the wave, preferably the reflected wave, the separation at the entire interface can be inspected nondestructively.

[Brief description of the drawings]

FIG. 1 is a view for explaining a first invention in a method for inspecting interface peeling of a polymer insulator tube of the present invention.

FIG. 2 is a diagram showing an interface between a jacket rubber of a normal product and an FRP core and a waveform of an echo.

FIG. 3 is a diagram showing an interface between a jacket rubber of a peeled product and an FRP core and a waveform of an echo.

FIG. 4 is a view for explaining another example of the method for inspecting interfacial peeling of a polymer insulator according to the present invention.

FIG. 5 is a diagram showing a configuration of another example in the inspection apparatus shown in FIG.

FIG. 6 is a view for explaining a second invention in the method for inspecting interface peeling of a polymer porcelain tube according to the present invention.

FIG. 7 is a diagram showing an implementation state of an interface peeling test in the example shown in FIG. 6;

FIG. 8 is a diagram showing a configuration of an example of a polymer insulator tube.

[Explanation of symbols]

1 polymer insulator, 2 FRP core, 3 outer rubber, 3
a outer shell, 3b shade, 4-1 and 4-2 metal fittings, 11
Water tank, 12-1, 12-2 Rotating device, 13-1, 13
-2 lateral displacement prevention device, 14 ultrasonic probe, 15-
1, 15-2 lid, 21 defective part, 22 submersible pump,
23 Nozzle, 31 Cylindrical body, 32 Pump with deaeration mechanism, 33 Water tank, 34-1, 34-2 Guide roller, 35 Ultrasonic flaw detector

Continuation of front page (72) Inventor Masayoshi Yasui 2-56 Suda-cho, Mizuho-ku, Nagoya-shi, Aichi Japan Insulator Co., Ltd.

Claims (7)

[Claims] 1. An interface peeling-off of a polymer porcelain tube comprising an FRP cylinder, a jacket rubber provided on an outer peripheral surface of the FRP cylinder and a cap and a body, and metal fittings provided on both ends of the FRP cylinder. In the inspection method, the polymer insulator tube and the ultrasonic probe are immersed in water, the ultrasonic probe irradiates the polymer insulator tube with ultrasonic waves from the rubber side, and the reflected wave is obtained. A method for inspecting interfacial peeling of a polymer porcelain tube, which comprises inspecting peeling. 2. The polymer porcelain tube is rotated about its central axis, and the ultrasonic probe is moved in the direction of the center axis of the polymer porcelain tube over the body of the metal fitting and the jacket rubber with respect to the rotated polymer porcelain tube. Irradiates an ultrasonic wave from an ultrasonic probe, obtains a reflected wave of the irradiated ultrasonic wave, and, based on the phase of the obtained reflected wave waveform, based on the interface between the body of the outer rubber and the FRP cylinder, the outer rubber and metal fittings. The method for inspecting interface peeling of a polymer porcelain pipe according to claim 1, wherein the interface is inspected for peeling at an interface between the FRP cylinder and a metal fitting, or at an interface between a joint rubber and a jacket rubber or between an FRP cylinder and a metal fitting. 3. The method according to claim 1, wherein the buoyancy of the polymer porcelain is utilized by immersing the polymer porcelain in water with lids provided at both ends of the FRP cylinder. 4. An apparatus according to claim 1, further comprising an adhering air bubble removing device for removing air bubbles adhering to the metal shell of the polymer insulator tube and the body surface of the outer cover rubber to prevent noise from being introduced by the air bubbles. The method for inspecting interfacial peeling of a polymer porcelain pipe according to the above. 5. An interface peeling of a polymer porcelain tube comprising an FRP cylinder, a covering rubber comprising a cap portion and a body provided on an outer peripheral surface of the FRP cylinder, and metal fittings provided at both ends of the FRP cylinder. In the inspection method, the water flow is continuously supplied to a cylindrical body having an ultrasonic probe therein, and the ultrasonic probe is in a state where water flowing out from an end of the cylindrical body is always in contact with a metal fitting or a body of a rubber jacket. Irradiates the ultrasonic wave to the metal fitting or the body of the outer rubber from, obtains a reflected wave of the irradiated ultrasonic wave, and based on the obtained reflected wave, an interface between the body of the outer rubber and the FRP cylinder,
A method for inspecting interface peeling of a polymer porcelain tube, comprising inspecting peeling at an interface between a jacket rubber and a metal fitting, at an interface at a joint portion between the jacket rubber and the metal jacket, or at an interface between an FRP cylinder and a metal fitting. 6. The method of claim 5, wherein the inspection of the separation at the interface is performed based on the phase of the obtained reflected wave. 7. The cylindrical body is provided with a guide roller, and the distal end of the cylindrical body is moved in the circumferential direction with respect to the polymer porcelain tube in a state where the distal end is always kept at a constant distance from the trunk portion of the rubber cover, and peels off. The method for inspecting interface peeling of a polymer porcelain tube according to claim 5 or 6, wherein the inspection is performed.