JP5992680B2 - Tracking prevention tool - Google Patents

Description

  The present invention relates to a tracking prevention tool attached to an insulated wire.

  When the insulation material of the insulated wire used in power equipment such as power distribution equipment is fouled by salt damage, a leakage current flows through the fouled portion. Due to this leakage current, the coating material is carbonized and tracking occurs.

  With regard to this tracking, the inventors of the present invention have found that the main cause of tracking is the generation of a dry belt. That is, when an insulation material such as a sheath of an insulated wire or an insulator used in a power facility such as a power distribution device is fouled by salt damage or the like, a leakage current flows through the fouled portion. Due to this leakage current, Joule heat is generated on the surface of the coating material, and heat is generated. Drying progresses due to heat generation, and the resistance of the dried portion increases. For this reason, a dry zone called a high-temperature dry belt (dry) is locally formed around the insulator. Most of the insulation voltage is applied to the dry belt. As the contamination further progresses, corona discharge and minute arcs are generated on the dry belt, and if the insulator is an organic material, carbonization occurs and tracking occurs. The substance generated by tracking contains a large amount of carbon and is conductive, which becomes an electric circuit and further promotes deterioration of insulation.

  Furthermore, even if the dry belt is generated by an inorganic material such as a porcelain insulator, the dry belt moves on an insulated wire having a diameter smaller than that of the insulator and a higher current density. For this reason, the dry belt initially generated in the porcelain insulator or the like may move onto the insulated wire covered with the organic material to cause tracking.

  On the other hand, apart from the tracking prevention tool, for example, Patent Document 1 discloses a power cable terminal processing tool constituted of a contraction tube. This terminal treatment tool is made of synthetic rubber, and is provided with a disk-shaped shallow shade, a cup-like deep shade, and a disk-like shallow shade on the outer periphery in order from the tip side. While protecting the covering material of the power cable by the tube main body, these caps increase the creeping distance and suppress the leakage current, thereby preventing the occurrence of tracking that occurs in the tube main body.

JP 2000-037027 A

While power cable end treatment tools are intended to insulate themselves from the ground, the “tracking prevention tools ” also have other objects that provide insulation from the ground. Is a completely separate device. Therefore, even when using the configuration of the terminal unit main body disclosed in Patent Document 1, the insulated wire connected to the tip is often narrower in diameter, and the dry belt shifts to the insulating wire. There is a problem that the tracking of the electric wire cannot be prevented.

  For this reason, it is effective to take measures on the insulated wire with the smallest diameter in order to prevent tracking. The dry belt is guided to a material that does not generate tracking, and the tracking generated on the insulated wire is prevented by sacrificing action. It is effective.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a tracking prevention tool in which tracking is difficult to occur.

In order to achieve the above object, the tracking preventive device of the present invention comprises:
It is formed from a silicone resin and includes a cylindrical main body portion that is attached to an insulated wire.

  It is provided at one end of the main body, and has one cap portion that extends in diameter toward the other end of the main body, covers a part of the main body, and exposes the other end. Good.

  The said cap part may be fixed to the position between 1/4 thru | or 1/3 of the length of the said main-body part from the end of the said main-body part.

  The shade portion may have a depth of ¼ to ¾ of an axial length of the main body portion.

  The main body may have a uniform outer diameter.

  The said cap part and the said main-body part may be formed integrally.

  The shade portion may be a separate body from the main body portion.

  The said cap part may have an opening.

  Each of the main body portion and the cap portion may have a cut extending from one end to the other end in the longitudinal direction of the main body portion and extending to the end portion of the cap portion.

  The main body may include a through hole into which an insulated wire is inserted, and may have a hole communicating with the through hole on the peripheral surface of the main body.

It is a perspective view of the tracking prevention tool which concerns on the 1st embodiment of this invention. FIG. 2 is a cross-sectional view of the tracking preventer shown in FIG. It is a figure of the state which attached and used the tracking prevention tool shown in FIG. 1 to the insulated wire pulled out from the bushing of the transformer. It is a figure which shows roughly the state when attaching the tracking prevention tool of FIG. 1 to an insulated wire. (A)-(E) is a figure which shows how a dry belt is produced | generated and moves with use of the tracking prevention tool of FIG. 1 with time. It is a perspective view of the tracking prevention tool which concerns on the 2nd embodiment of this invention. FIG. 7 is a cross-sectional view of the tracking prevention tool shown in FIG. 6 taken along the line BB. It is a perspective view of the tracking prevention tool which concerns on the 3rd embodiment of this invention. It is CC sectional view taken on the line of the tracking prevention tool shown in FIG. It is a see-through | perspective perspective view of the tracking prevention tool which concerns on the 4th embodiment of this invention. It is the DD sectional view taken on the line of the tracking prevention tool shown in FIG.

Tracking preventer according to an embodiment of the present invention, the cause of tracking based on the present inventor's finding that in Doraiberu bets, while having a simple configuration, has a structure to fasten the dry belt in the tracking preventer Is. Hereinafter, a tracking prevention tool according to an embodiment will be specifically described with reference to the drawings.

(First embodiment)
The tracking prevention device according to the present embodiment controls the initial generation position of the dry belt and the subsequent movement path while having a simple and small structure, so that the dry belt stays on the tracking prevention device and covers the power line (insulated wire). It has a function of preventing tracking by guiding it so as not to move on the material.

  As shown in FIGS. 1 and 2, the tracking prevention tool 10 includes a main body portion 14 and a cap portion 16 provided on the main body portion 14.

  The main body portion 14 is formed in a cylindrical shape or a tube shape having a through hole 14h through which the insulated wire 12 passes.

  The diameter D1 of the through-hole 14h penetrating the main body 14 is slightly larger than the outer diameter of the insulated wire to be disposed, and is formed so as to adhere to the covering material of the insulated wire 12 by silicone caulking or the like in the mounted state. . Moreover, the outer diameter of the main-body part 14 is formed uniformly. Furthermore, the diameter D1 of the through hole 14h may be substantially equal to the outer diameter of the insulated wire 12, and may be formed in close contact with the covering material of the insulated wire 12 without using an adhesive in the mounted state.

  The cap portion 16 is fixed to the main body portion 14 in the vicinity of the one end portion 14 a of the main body portion 14, is formed coaxially with the main body portion 14, and extends in the direction of the other end portion 14 b of the main body portion 14. The shade portion 16 covers the upper portion of the main body portion 14 and makes it difficult for the main body portion 14 to be affected by fouling due to salt damage or wetness due to rainfall.

  The main body 14 and the cap 16 are made of silicone rubber and are integrally molded. Here, a silicone rubber means a rubber-like thing among silicone resins (synthetic resin which has silicone as a main component). Silicone is a general term for artificial polymer compounds having a main skeleton formed by siloxane bonds. Siloxane is a processed product having a skeleton of silicon and oxygen and is a general term for those having Si—O—Si bonds (siloxane bonds). Silicone rubber does not produce carbides when forming a dry belt.

  A cut 18 is formed in the main body 14 and the cap 16 along the long axis of the main body 14 (see FIG. 4). The cut 18 enables the tracking prevention tool 10 to be easily attached to an existing insulated wire as will be described later.

  Further, the depth L4 of the cap portion 16 is formed to be 1/2 to 1/3 of the handle length L1 of the main body portion 14. The cap portion 16 is disposed in a range of 1/4 or less of L1 from the one end 14a of the main body portion 14. As will be described later, this is because the dry belt moves below the main body 14 (in the direction in which the shade spreads), so that a movable distance is secured.

  Moreover, the length L2 of the part which protruded above the cap part 16 among the main-body parts 14 is designed by about 0.5 cm to 2 cm. Longer than this is not a problem, but it does not contribute to the generation and movement of the dry belt and is wasted.

  The thickness L3 of the cap portion 16 is formed so as not to bend or close, for example, about 1 to 8 mm, preferably 2 to 5 mm.

  Further, the radius D2 of the shade portion 16 depends on the applied voltage of the insulated wire 12, and is determined by the thickness of the air layer that can obtain the withstand voltage for the applied voltage × the safety factor. For example, if the applied voltage of the power line is 3.8 kV, the diameter is designed so that the value of L7 is 1 cm to 2 cm.

  The diameter D1 of the through hole 14h of the main body 14 is formed to be approximately the same as or slightly larger than the diameter of the insulated wire to be protected.

  Further, the thickness T1 of the main body portion 14, the thickness L3 of the cap portion 16, and the diameter D1 of the through-hole 14h of the main body portion 14 are set based on the relationship between the withstand voltage and the cost. T1 is formed to be 2 to 8 mm, preferably 2 to 5 mm, for example, when the tracking prevention tool 10 is used for a three-phase transformer having a working voltage of 3.8 kV. In addition, when a dry belt generate | occur | produces in the main-body part 14 and the cap part 16, the erosion which those surfaces cut off will occur. The thicknesses T1 and L3 of the main body 14 and the cap 16 are designed so that a sufficient withstand voltage can be obtained during the years of use even if erosion occurs.

  Next, how the tracking prevention tool 10 is used will be described.

  As shown in FIG. 3, the tracking preventing device 10 is formed from, for example, a bushing 52 of the pole transformer 50 so that the cap portion 16 is located in a convex state upward and a portion corresponding to the shade pattern is located below. The lead wire (insulated wire) 12 is attached to the lead wire (insulated wire) 12 while being exposed to the outside air.

  When the tracking prevention tool 10 is attached to the lead wire 12, in the case of a lead wire of a newly installed transformer, the lead wire is inserted into the main body 14 and bonded by silicone caulking. In addition, when attaching to the lead wire of an existing transformer, as shown in FIG. 4, the cap portion 16 and the main body portion 14 are opened from the cut 18, and after applying the silicone caulk, the lead wire 12 is connected from the cut 18 to the main body portion 14. It is done by putting in. After mounting, the outer surface of the lead wire 12 and the through hole 14h are bonded by silicone caulking.

  The adhesion between the outer surface of the lead wire 12 and the through hole 14h is not limited to the case where an adhesive such as silicone caulking is used, and is brought into a close contact state by the restoring force due to the elasticity of the main body 14 and the cap 16. You can also.

  Next, with reference to FIG. 5, a state where a dry belt is formed on the tracking prevention tool 10 and the dry belt moves will be described. In addition, since the silicone resin used for the tracking prevention tool 10 has water repellency, it has the characteristic that a dry belt is more easily formed than an organic insulating material.

  When the tracking prevention tool 10 is used in the form shown in FIG. 3, since the inside of the cap portion 16 has little fouling and high initial resistance at the beginning of use, the dry belt 22 is as shown in FIG. The inner surface 16c of the cap portion 16 is formed. Salt crystals are formed on the surface where the dry belt is formed, and are damaged. At this time, if there is rain, the contaminated portion is cleaned, and the insulation breakdown voltage of the entire tracking prevention device 10 including the lead wire 12 is temporarily increased, so that the dry belt 22 disappears. As the stain progresses further, the dry belt 22 shifts to the next least contaminated portion (FIG. 5B → FIG. 5C). Each time the rain falls, the contaminated portion is cleaned, and the dry belt 22 moves as shown in FIGS. 5D and 5E.

  As further fouling progresses, salt crystals are washed away by the deliquescence of magnesium chloride contained in seawater and move to the first occurrence site.

  While the movement of the dry belt is repeated several times, the main body 14 and the cap 16 where corona discharge and minute arc are generated are made of silicone rubber that does not generate carbides. Although the erosion that cuts the surface of the steel occurs, it does not carbonize and the occurrence of tracking can be prevented.

It takes several decades for the tracking preventive tool 10 to have its surface scraped by erosion and reach the covering material of the lead wire 12. Thus, during the service life of the pole transformer 50, the dry belt 22 can be prevented from being moved onto the lead 12, it is not necessary to replace the tracking preventer 10.

As described above, the tracking preventer 10 according to this embodiment is formed of a silicone resin, a cylindrical body portion 14 for covering the insulated wire 12, disposed in the body portion 14, the main body portion 14 And one cap portion 16 that extends and extends in diameter.

With this configuration, the dry belt 22 that causes tracking is covered by the concave surface of the cap portion 16 (FIG. 5A → FIG. 5B) → the cap portion 16 of the main body portion 14. portions are (Fig. 5 (C) → FIG. 5 (D)) → induced to sequentially generate and move portion exposed from the cap portion 16 of the body portion 14 (FIG. 5 (E)). For this reason, the dry belt 22 does not occur on the insulating coating of the insulated wire 12.

  It has not been known in the past that the main cause of tracking is the dry belt, and until now it has been trying to prevent tracking by strengthening the insulator. However, in practice, the generation of dry belts is concentrated on lead wires that are smaller in diameter than insulators and have a low thermal conductivity, and it has been found that dry belts generated on insulators always shift to lead wires. Therefore, as described in the present embodiment, by installing the tracking prevention tool 10 on the lead wire, the dry belt based on the above phenomenon can be fastened to the tracking prevention tool 10 and the occurrence of tracking can be prevented.

  Further, by forming the tracking prevention device 10 from silicone rubber that does not generate carbides, even if corona discharge or a slight arc occurs on the dry belt 22, only erosion that scrapes the surfaces of the main body 14 and the cap portion 16 occurs. Carbonization does not occur. Therefore, even if a dry belt is generated on the tracking prevention tool 10, no tracking occurs.

  In addition, the tracking prevention tool 10 of this embodiment and the electric power cable terminal processing tool of patent document 1 have a common part in the point provided with a shaft part and a cap part. However, while the power cable terminal processing tool is used at the boundary part between the charged side and the non-charged side, the tracking prevention tool of this embodiment is installed in the middle of the electric circuit or at the boundary part insulated by a porcelain insulator or the like. Therefore, both sides of the apparatus are completely different from each other in that they are used in charged portions.

(Modification)
In the present embodiment, the shade portion 16 is bowl-shaped, but if the shade portion 16 can have an inner surface that expands in the direction from the position where it is provided to the main body portion 14 toward the other end portion 14b, it is a skirt shape or a cup shape. It can be made into arbitrary shapes, such as.

  Further, the shape of the main body 14 is not limited to a cylindrical shape, and may be any shape such as an elliptical cylindrical shape or a polygonal cylindrical shape. However, it is desirable that the outer diameter is uniform.

  Although the cut 18 is provided in the main body 14 and the cap 16, in the case of a lead wire of a newly installed transformer, the lead 18 can be inserted into the main body 14, so the cut 18 is not always necessary.

  It is desirable that the main body portion 14 and the shade portion 16 are integrally formed so that salt damage due to salt damage, dust, or moisture due to rainfall does not enter between them. However, if the strength of the joint portion between the two can be maintained, they can be formed of separate members. In this case, the main body portion 14 and the cap portion 16 can be bonded with an adhesive having excellent weather resistance, such as a silicone adhesive.

  The length and thickness of the main body portion 14 and the cap portion 16 of the tracking prevention device 10 are not limited to the above-described values, but vary depending on the voltage used for the insulated wire to which the tracking prevention device 10 is attached and the number of years scheduled for use.

  Moreover, although the position where the cap part 16 was provided was made into the position of 1 cm from the one end part 14a of the main-body part 14, it is not limited to this, The position is arbitrary.

(Second Embodiment)
In the first embodiment, the cap portion 16 completely covers a part of the main body portion 14. However, if the dry belt can be guided to the main body portion, an opening is formed in a part of the cap portion 16. It may be.

  Hereinafter, a second embodiment having such a configuration will be described.

  As shown in FIGS. 6 and 7, the tracking prevention tool 80 according to the present embodiment includes a cylindrical main body portion 84 and a cap portion 86 provided on a peripheral surface near one end of the main body portion 84.

  The shade portion 86 has four openings 88 (only three are shown in FIG. 6). Even when it rains on the main body 84 through the opening 88 and a fouling substance such as salt or dust adheres to the main body 84 when it rains, the fouling substance can be washed to some extent. The main body portion 84 and the shade portion 86 are bonded by an arbitrary adhesive.

  The main body 84 is attached to the lead wire 82 of the power distribution device, similarly to the main body 14 of the tracking prevention tool 10 of FIG.

  According to such a configuration, the dry belt is first formed on the inner surface of the shade portion 86, and then moves to the portion covered with the shade portion 86 of the main body portion 84. However, since the main body 84 is washed to some extent by rain or the like, the movement of the dry belt is restricted or the generated dry belt disappears.

  For this reason, even if a dry belt is generated, it takes a long time to reach the other end 84b of the main body 84, and it is possible to effectively prevent tracking even with a small size.

  Since the shade part 86 of this embodiment is provided with the opening 88, the depth is set to, for example, about 3/4 to 1/4 of the length corresponding to the handle part of the shade part. It may be deeper than the shade portion 16 of the form.

  In FIG. 7, the main body portion 84 and the shade portion 86 are shown as separate structures, but the body portion 84 and the shade portion 86 can be formed integrally as in the tracking prevention device 10 of the first embodiment. It is.

  In the present embodiment, the four openings 88 are formed in the shade portion 86. However, in order to reduce or enhance the rain-washing effect according to the climate of the area where the tracking prevention device is attached, any number and size may be used. it can. For example, in areas where there is a lot of rain, the total area of the openings 88 is reduced. In areas where there is little rain, the area of the openings 88 is increased. In areas where there is a large amount of salt damage, the total area of the openings 88 is increased. In a small area, the total area of the openings 88 can be reduced. The shape of the opening 88 is arbitrary such as a circle, an ellipse, and a rectangle.

(Third embodiment)
In the first and second embodiments, the tracking prevention devices 10 and 80 are configured by the main body portions 14 and 84 and the shade portions 16 and 86, but may be configured by only the main body portion.

  Hereinafter, the tracking prevention tool 90 having such a configuration will be described.

  As shown in FIGS. 8 and 9, the tracking prevention tool 90 according to the present embodiment includes a cylindrical main body 94.

  Even when rain hits the main body portion 94 and a contaminating substance such as salt or dust adheres to the main body portion 94, the contaminating substance can be washed to some extent.

  The main body portion 94 is attached to the lead wire 92 of the power distribution device in the same manner as the main body portion 14 of the tracking prevention tool 10 of FIG.

  For example, when the tracking prevention device 90 is attached to an insulated wire with low water repellency or an existing wire that has deteriorated and lost water repellency, the dry belt generated on the insulated wire or the existing wire is made of the silicone rubber of the tracking prevention device 90. Due to the water repellency, the main body 94 of the tracking prevention tool 90 is transferred. As a result, the occurrence of tracking can be prevented as in the above embodiment.

  According to experiments, in the first and second embodiments having a cap portion, of the time from the generation of the dry belt to the disappearance of the dry belt, the time ratio of the dry belt on the tracking prevention devices 10 and 80 is about 80%. However, even the tracking prevention tool 90 having no cap portion has about 50%, and has an effect of sufficiently suppressing the occurrence of tracking.

  According to such a configuration, the dry belt is generated in the main body portion 94, but since the main body portion 94 is washed to some extent by rain or the like, the movement of the dry belt is restricted or the generated dry belt disappears.

  Therefore, even if a dry belt is generated, it takes a long time to reach the other end 94b of the main body 94, and it is possible to effectively prevent tracking even with a small size.

(Fourth embodiment)
In the tracking prevention tool 10 of the first embodiment, the cut 18 is provided in the main body portion 14 for attachment to the existing lead wire 12, but in the tracking prevention tool 100 of the present embodiment, the cut 18 is provided. It is the structure which can be attached to the existing lead wire 12 without.

  As shown in FIGS. 10 and 11, the tracking prevention tool 100 includes a main body portion 104 and a cap portion 106 provided on the main body portion 104.

  On the peripheral surface near the center of the main body 104, a filling hole 104j communicating with the through hole 104h is formed.

  In the case of the lead wire 102 of the newly installed transformer, the tracking prevention device 100 is attached to the lead wire 102 by inserting the lead wire 102 from one end of the main body 104 and passing the silicone caulking from the filling hole 104j to the through hole 104h and the lead wire. The lead wire 102 is bonded to the through hole 104h by filling the space between the outer surface of the lead wire 102 and the through hole 104h.

  In addition, when attaching to the existing lead wire 102, first, the lead wire 102 is cut, and the covering material of the lead wire 102 is peeled off from both cut surfaces to expose the conductor 102a, for example, by about 5 mm. A cylindrical connection member 103 made of, for example, silicone resin is attached to one conductor 102 a of the cut lead wire 102, and in this state, the lead wire 102 is connected to the through hole 104 h of the main body 104 together with the connection member 103 from one end thereof. Insert. The other end of the cut lead wire 102 is inserted from the other end of the main body 104, and the conductor 102a is brought into contact with one conductor 102a in the connection member 103 to be electrically connected. Thereafter, silicone caulk is filled from the filling hole 104j between the through hole 104h and the connection member 103, between both the conductors 102a and the connection member 103, and between the through hole 104h and the outer surface of both the lead wires 102. Then, both lead wires 102 are bonded to the through hole 104h.

  The diameter of the connecting member 103 can be designed to an arbitrary value as long as the connecting member 103 can be inserted into the through hole 104 h of the main body 104. The diameter of the through hole of the connection member 103 can be designed to an arbitrary value as long as the conductor 102a can be inserted.

  Thus, this embodiment can attach the tracking prevention tool 100 to a new installation and the existing lead wire easily.

(Modification)
Although this embodiment is provided with the shade 106, a configuration without the shade may be used.

  In the first to fourth embodiments, etc., the example in which the tracking prevention device of the present invention is applied to the pole transformer has been shown. However, in addition to the transformer, disconnectors, circuit breakers, transformers, switches, etc. It can also be applied to facilities that use insulated wires.

  Moreover, although the case where the tracking prevention tool of this invention was used for the insulated wire of a transformer was shown, it can be used also in the vicinity which supports insulated wires, such as a distribution line, a lead-in wire, and an overhead wire, with an insulator.

  The present invention is not limited to the above-described embodiment and the like, and various modifications and changes can be made within the scope of the claims.

10, 80, 90, 100 ... Tracking prevention tool 12, 82, 92, 102 ... Lead wire (insulated wire)
14, 84, 94, 104 ... main body 14h, 104h ... through hole 16, 86, 106 ... shade 18 ... cut 88 ... opening 104j ... filling hole

Claims (9)

  A cylindrical main body formed from silicone resin and attached to an insulated wire, provided at one end of the main body, and extending in diameter toward the other end of the main body. And a cap portion that exposes the other end portion, and the cap portion has an opening. The thickness of the main body is 2 to 8 mm, and the thickness of the cap is 1 to 8 mm.
The tracking prevention tool according to claim 1 . The cap is fixed in a range of 1/4 or less of the length of the main body from one end of the main body.
The tracking prevention tool according to claim 1 or 2 . The cap portion has a depth of ¼ to ¾ of the axial length of the main body portion,
The tracking prevention tool according to any one of claims 1 to 3 . The length of the main body portion that protrudes from the cap portion toward the one end is 0.5-2 cm.
The tracking prevention tool according to any one of claims 1 to 4 . The said cap part and the said main-body part are integrally formed,
The tracking preventing tool according to any one of claims 1 to 5 . The cap portion is separate from the main body portion,
The tracking preventing tool according to any one of claims 1 to 5 . The main body portion and the cap portion each have a cut extending from one end to the other end in the longitudinal direction of the main body portion and extending to the end portion of the cap portion,
The tracking prevention tool according to any one of claims 1 to 7 . The main body includes a through hole into which an insulated wire is inserted, and has a hole communicating with the through hole on the peripheral surface of the main body.
The tracking preventing tool according to any one of claims 1 to 8 .

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