CN112310912A

CN112310912A - Wall bushing

Info

Publication number: CN112310912A
Application number: CN202011015775.8A
Authority: CN
Inventors: 黄从鹏; 刘超; 马斌
Original assignee: Jiangsu Shenma Electric Power Co Ltd
Current assignee: Jiangsu Shenma Electric Power Co Ltd
Priority date: 2020-09-24
Filing date: 2020-09-24
Publication date: 2021-02-02

Abstract

The invention discloses a wall-penetrating bushing, comprising a head assembly, a conductive rod, a protective bellows and a terminal; the head assembly is provided with a accommodating cavity, and the upper end and the lower end of the head assembly are respectively coaxially arranged to communicate with the accommodating cavity The first through hole and the second through hole of the protective bellows is a ring-shaped shell that penetrates up and down, the protective bellows is respectively provided with an upper through hole and a lower through hole, and the conductive rod passes through the first through hole, the second through hole, The upper through hole and the lower through hole, the lower through hole is fixedly connected with the conductive rod, the terminal is electrically connected with the conductive rod, and the head assembly and the conductive rod are sealed and covered. The wall-penetrating sleeve has a simple structure, and the head assembly replaces the traditional bellows structure, which can avoid the use of an axial dynamic sealing device, greatly improve the product sealing reliability, and at the same time can reduce production costs; the setting of protective bellows further prevents possible The metal chips or other debris can enter the main insulation cavity of the wall bushing to improve the reliability of product operation.

Description

Wall bushing

Technical Field

The application relates to the technical field of power transmission insulating equipment, in particular to a wall bushing.

Background

In the direct current transmission and transformation project, the wall bushing is used as the only electrical element for connecting the inside and the outside of the valve hall, bears the full voltage and the current of the whole line, and the performance reliability of the wall bushing is related to the operation safety and the stability of the whole line.

At present, the sheathed tube head subassembly of current wall of wearing is mostly the bellows, axial sealing connection is taken with the bellows to the conducting rod, the conducting rod passes the bellows and directly is connected with the external part electricity, specifically speaking, the one end and the sheathed tube end of wall of conducting rod are together fixed, the other end and the bellows of conducting rod are fixed and are stretched out the bellows outside and be connected with the external part electricity, thereby possess elastic bellows to provide the tensioning that the tensile force keeps the conducting rod to the conducting rod, when the conducting rod is heated and elongated, elastic deformation can take place for the bellows, make the conducting rod still keep straight state, stress bending can not take place, but there is following problem: when the head assembly of the wall bushing adopts the corrugated pipe, if axial sealing is adopted, the long-term reliability of the dynamic sealing cannot be ensured due to the friction effect of long-term expansion and contraction, and the product is easy to leak gas; if axial sealing is not adopted, an external transition tank needs to be additionally arranged, the wiring terminal and the conducting rod need to be in flexible connection, and the through-current capacity is limited; the corrugated pipe is high in price, so that the manufacturing cost of the product is increased; metal chips are easily generated between the conductive rod and the head assembly due to friction, resulting in internal discharge.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide a wall bushing which is simple in structure, a head assembly replaces the traditional corrugated pipe structure, an axial dynamic sealing device can be avoided, the sealing reliability of a product is greatly improved, and meanwhile, the production cost can be reduced; the arrangement of the protective corrugated pipe further prevents metal chips or other scraps which are possibly generated from entering the interior of the main insulating cavity of the wall bushing, and the operation reliability of the product is improved.

In order to achieve the purpose, the technical means adopted by the invention are as follows: a wall bushing comprises a head assembly, a conductive rod, a protective corrugated pipe and a wiring terminal; the head assembly is provided with a containing cavity, the upper end and the lower end of the head assembly are respectively coaxially provided with a first through hole and a second through hole communicated with the containing cavity, the protective corrugated pipe is an annular shell which is communicated from top to bottom, the protective corrugated pipe is respectively provided with an upper through hole and a lower through hole, the conducting rod penetrates through the first through hole, the second through hole, the upper through hole and the lower through hole, the protective corrugated pipe is provided with an upper connecting end around the upper through hole, the upper connecting end is fixedly connected with the lower end of the head assembly around the second through hole, the lower through hole is fixedly connected with the conducting rod, the connecting terminal is electrically connected with the conducting rod and is provided with. The wall bushing is simple in structure, the head assembly replaces the traditional corrugated pipe structure, an axial dynamic sealing device can be avoided, the sealing reliability of a product is greatly improved, and meanwhile, the production cost can be reduced; the arrangement of the protective corrugated pipe further prevents metal chips or other scraps which are possibly generated from entering the interior of the main insulating cavity of the wall bushing, and the operation reliability of the product is improved.

Preferably, the upper connecting end is a flange plate extending along the radial direction of the upper through hole, and the flange plate is attached and fixedly connected with the lower end part of the head assembly. The flange plate and the head component are connected by adopting a disc plate type plane, so that the installation is convenient and the structure is reliable.

Preferably, a mounting hole is formed in the flange plate, a channel communicated with the upper through hole is formed between the mounting hole and the upper through hole, the filter element is mounted in the mounting hole, and the filter element is only used for gas exchange between the inside of the protection corrugated pipe and the outside of the protection corrugated pipe. The wall bushing only allows gas to pass through in the inflation and deflation process, and impurities, metal chips and the like in the wall bushing cannot enter the insulating main cavity through the filter element.

Preferably, the filter element is a metal mesh structure. For example, the titanium rod filter element is a porous filter element which is prepared by taking industrial high-purity titanium as a raw material, carrying out static pressure forming through screening, cooling and the like, and then carrying out high-temperature and high-vacuum sintering, and has excellent performances of corrosion resistance, high-temperature resistance, high strength, easy guarantee of filter precision, easy regeneration and the like.

Preferably, the diameter of the lower through hole is smaller than the minimum inner diameter of the protection corrugated pipe, the lower connecting end is arranged around the lower through hole, the first round nut and the second round nut are arranged on two sides of the lower connecting end respectively, and the first round nut and the second round nut are connected with the conducting rod through threads respectively to clamp the lower connecting end so that the protection corrugated pipe is fixedly connected with the conducting rod. On one hand, the protective corrugated pipe is fixedly connected with the conducting rod, so that no gap exists between the protective corrugated pipe and the conducting rod, and impurities and metal chips in the protective corrugated pipe cannot enter the insulating main cavity; on the other hand, the conducting rod is deformed under the condition of expansion with heat and contraction with cold, the protection corrugated pipe is provided with a certain elastic deformation space, the size can be correspondingly changed along with the deformation of the conducting rod, and the stable connection relation between all parts of the wall bushing is ensured.

Preferably, the head assembly comprises a transition tank and a transition plate connected to each other; the upper end part of the transition tank is provided with a first through hole, and the lower end part of the transition tank is communicated with the first through hole; the transition plate is provided with a second through hole, and the transition tank and the transition plate are fixedly connected so that an accommodating cavity is formed in the transition tank by surrounding the conducting rod. The transition tank is a rigid component, the arrangement of the transition tank replaces the traditional corrugated pipe structure, an axial dynamic sealing device can be avoided, the sealing reliability of a product is greatly improved, and meanwhile, the production cost can be reduced.

Preferably, the circumferential inner wall of the transition tank is provided with a plurality of annular grooves. The annular groove serves as a particle capture trap to adsorb metal particles in the transition tank, and the stable electrical performance of the head of the wall bushing is ensured.

Preferably, a threaded hole is formed in one surface, attached to the transition plate, of the flange plate, a through hole corresponding to the threaded hole is formed in the transition plate, and the flange plate is in threaded connection with the transition plate through a bolt. The connecting structure is more convenient for assembling the wall bushing.

Preferably, the upper surface of the transition plate is provided with a convex ring around the second through hole, and the convex ring is positioned in the accommodating cavity. The arrangement of the convex ring increases the supporting area of the conducting rod, and the bending resistance of the conducting rod can be improved.

Preferably, the inner wall of the first through hole and/or the inner wall of the second through hole and/or the inner wall of the bulge loop is provided with a non-metallic lining. The nonmetal liner prevents the conducting rod from generating metal chips due to friction with the transition plate and the transition tank, and improves the running reliability of the product.

Preferably, the inner wall of the convex ring is provided with a plurality of grooves, and the non-metal lining is embedded into the grooves. The structure can adopt a broken ring form to embed the non-metal lining into the groove. On one hand, the using amount of the non-metal lining can be reduced, and the production cost is reduced; on the other hand, the nonmetal inner lining embedding groove inner wall of broken ring form is in the same place as the nonmetal inner lining whole piece of the bigger area and is arranged on the inner wall of the convex ring, so that the installation and fixation are more convenient, and the condition that the nonmetal inner lining displaces on the inner wall of the convex ring can not occur in the using process.

Preferably, the connection terminal includes a connection portion, a receiving portion and a connection portion in sequence, the receiving portion is used for receiving an end portion of the conductive rod and electrically connected with the conductive rod, and the connection portion is connected with an upper end portion of the head assembly in a sealing manner. The wiring terminal is an electric connection component of the wall bushing and is used for being electrically connected with other equipment. The connecting part is convenient for fixedly connecting the wiring terminal with the transition tank.

Preferably, the end of the conducting rod is provided with a spring contact finger, the spring contact finger abuts against the inner wall of the accommodating part, and a gap exists between the accommodating part and the end of the conducting rod along the axial direction of the conducting rod. The spring contact fingers are simultaneously in close contact with the end parts of the wiring terminal and the conducting rod, so that stable electric connection is formed between the end parts of the wiring terminal and the conducting rod, the equipotential of the head assembly can be kept, and the problem of head heating is solved. There is the clearance along the axial of conducting rod between the tip of holding portion and conducting rod, can absorb the deformation of conducting rod expend with heat and contract with cold, avoids the conducting rod to produce the bending because of fixed connection.

Preferably, the wall bushing further comprises a hollow insulator, the hollow insulator is connected with the transition plate in a sealing mode, and the conducting rod penetrates through the hollow insulator. The hollow insulator provides insulation protection for the inner conductor of the wall bushing.

Drawings

FIG. 1 is a partial cross-sectional view of a wall bushing 100 according to a first embodiment of the invention;

fig. 2 is a perspective view of a protective bellows 150 according to a first embodiment of the present invention;

fig. 3 is a cross-sectional view of a cartridge 160 according to a first embodiment of the present invention;

FIG. 4 is a partial cross-sectional view of a wall bushing 200 according to a second embodiment of the present invention;

FIG. 5 is a partial cross-sectional view of a wall bushing 300 according to a third embodiment of the present invention;

fig. 6 is a sectional view of a connection terminal 340 of a third embodiment of the present invention;

FIG. 7 is a partial cross-sectional view of a wall bushing 400 according to a fourth embodiment of the invention;

fig. 8 is an overall cross-sectional view of a wall bushing 400 according to a fourth embodiment of the invention.

Detailed Description

As required, detailed embodiments of the present invention are disclosed herein. However, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed manner, including employing various features disclosed herein in combination with features that may not be explicitly disclosed herein.

The first embodiment is as follows:

as shown in fig. 1-3, the present embodiment provides a wall bushing 100, which includes a head assembly 110, a conductive rod 120, a protective bellows 150, and a terminal block 140; head subassembly 110 is equipped with and holds chamber 113, head subassembly 110 upper end and lower extreme coaxial setting respectively and hold first through-hole 1111 and second through-hole 1121 that chamber 113 communicates, protection bellows 150 is the annular casing that link up from top to bottom, protection bellows 150 sets up through-hole 151 and lower through-hole 152 respectively, conducting rod 120 passes first through-hole 1111, second through-hole 1121, go up through-hole 151 and lower through-hole 152, protection bellows 150 sets up upper connection end 153 around last through-hole 151, upper connection end 153 surrounds second through-hole 1121 and is connected with the lower extreme fixed connection of head subassembly 110, lower through-hole 152 is connected with conducting rod 120 fixed connection, binding post 140 is connected with conducting rod 120 electricity and the sealed cover is established head subassembly 110 and conducting rod 120. The wall bushing 100 is simple in structure, the head assembly 110 replaces the traditional corrugated pipe structure, an axial dynamic sealing device can be avoided, the sealing reliability of a product is greatly improved, and meanwhile, the production cost can be reduced; the provision of the protective bellows 150 further prevents metal filings or other debris that may be generated from entering the interior of the main insulating cavity of the wall bushing 100, improving the operational reliability of the product.

In this embodiment, the upper end portion and the lower end portion of the head assembly 110 are relative positions, and the end close to the head assembly 110 is upward and the end away from the head assembly 110 is downward along the axial direction of the entire structure of the wall bushing 100. In other embodiments, the definition of "up" and "down" is also in accordance with this standard.

In this embodiment, the protection bellows 150 is a circular ring-shaped housing, and in other embodiments, the shape of the circular housing of the protection bellows may be set to other shapes, such as a square ring, an elliptical ring, and the like, and is not limited to a circular ring.

In this embodiment, the upper connection end 153 is a flange 153 extending outward in the radial direction of the upper through hole 151, and the flange 153 is engaged with and fixedly connected to the lower end portion of the head unit 110. The flange plate 153 is connected with the head assembly 110 by adopting a plate-plate plane, so that the installation is convenient and the structure is reliable.

In other embodiments, the structure of the upper connection end is not limited to this, for example, the upper connection end may be a circular ring structure or a sawtooth structure extending along the upper through hole, and the lower end of the head assembly is provided with a groove matched with the lower end of the head assembly for insertion and connection, and is fixed by an adhesive in an auxiliary manner.

In this embodiment, a mounting hole 1531 is disposed on the flange 153, a channel 1532 is disposed between the mounting hole 1531 and the upper through hole 151, the filter element 160 is mounted in the mounting hole 1531, and the filter element 160 only provides gas exchange between the inside of the protection bellows 150 and the outside of the protection bellows 150. In the process of inflating and deflating the wall bushing 100, the filter element 160 only allows gas to pass through, and the impurities and metal chips inside cannot enter the insulating main cavity through the filter element 160.

In this embodiment, the number of the mounting holes 1531 is 3, and the number of the corresponding filter cartridges 160 is also three. In other embodiments, the number of the mounting holes and the number of the filter elements are equal, and the specific number and the distance between different mounting holes are not particularly limited.

In this embodiment, the mounting hole 1531 is a through hole, and the passage 1532 is disposed on the surface of the flange 153 and is a linear groove communicating the mounting hole 1531 with the upper through hole 151. The passage 1532 is a passage for exchanging gas between the inside of the protective bellows 150 and the outside of the protective bellows 150.

In other embodiments, the mounting holes are not through holes, and a channel is provided between the bottom end of the mounting hole and the upper through hole, the channel being disposed inside the flange and not visible from the surface of the flange. In short, the shape and the position of the passage are not limited as long as the purpose of exchanging gas between the inside of the protection bellows and the outside of the protection bellows can be achieved.

In the present embodiment, the cartridge 160 includes a filter portion 161 and a cartridge connecting portion 162. The filter unit 161 is a cylindrical metal sintered mesh, the side surface 1611 and the top surface 1612 of the filter unit 161 are integrally designed and connected in a seamless manner, the bottom surface 1613 of the filter unit 161 is provided with a through hole 1614, the filter element connecting portion 162 is arranged around the through hole 1614, the filter element connecting portion 162 is a vertically through cylinder structure, one end of the filter element connecting portion is connected with the through hole 1614, the other end of the filter element connecting portion is an outlet, and the filter element connecting portion 162 is provided with threads 1621. The mounting hole 1531 is provided with a thread matching with the thread 1621, and when the filter cartridge connecting portion 162 is mounted in the mounting hole 1531, the exposed portion of the filter cartridge 160 is integrally formed and seamlessly connected.

In this embodiment, the filter element 160 is a titanium rod filter element 160 with a metal mesh structure, and the titanium rod filter element 160 is a porous filter element formed by using industrial high-purity titanium as a raw material, performing static pressure forming through sieving, cooling and the like, and performing high-temperature and high-vacuum sintering, and has excellent performances of corrosion resistance, high-temperature resistance, high strength, easy guarantee of filter precision, easy regeneration and the like.

In this embodiment, the titanium rod filter element 160 has the following product characteristics: the structure is uniform, the pore size distribution is narrow, and the separation efficiency is high; the porosity is high, the filtration resistance is small, and the permeation efficiency is high; high temperature resistance, and can be normally used below 280 ℃; the chemical stability is good, the acid and alkali corrosion resistance is high, and the oxidation resistance is high; no particles fall off; good mechanical property and simple operation.

In other embodiments, the filter element may also be made of other sintered mesh materials, such as polytetrafluoroethylene, stainless steel, etc., which are corrosion-resistant, high-temperature resistant, strong in strength, and easy to ensure the filtering precision.

In this embodiment, the diameter of the lower through hole 152 is smaller than the minimum inner diameter of the protective corrugated tube 150, a lower connection end 154 is disposed around the lower through hole 152, a first round nut 156 and a second round nut 157 are disposed on two sides of the lower connection end 154, respectively, and the first round nut 156 and the second round nut 157 are screwed with the conductive rod 120 to clamp the lower connection end 154 so that the protective corrugated tube 150 is fixedly connected with the conductive rod 120. On one hand, the protective corrugated pipe 150 is fixedly connected with the conducting rod 120, so that no gap exists between the protective corrugated pipe 150 and the conducting rod 120, and impurities and metal chips in the protective corrugated pipe 150 are prevented from entering the insulating main cavity; on the other hand, the conductive rod 120 deforms when expanding with heat and contracting with cold, the protection bellows 150 has a certain space of elastic deformation, and the size of the protection bellows changes correspondingly along with the deformation of the conductive rod 120, so that the stable connection relationship between the components of the wall bushing 100 is ensured.

In other embodiments, the fixed connection between the protection corrugated pipe and the conducting rod may be welding, gluing, or other fixed connection methods, and the fixed connection between the two has no requirement on sealing.

In this embodiment, the protection bellows 150 is made of metal, and the protection bellows 150 made of metal can also play a role in shielding, thereby improving the operational reliability of the product.

In other embodiments, the protection bellows may also be made of a non-metal material, as long as it is ensured that metal chips are not generated between the protection cover and the conductive rod due to secondary friction.

It can be understood that, in the present embodiment, due to the arrangement of the protection bellows 150, a cavity which is formed by the protection bellows 150, the conducting rod 120, the transition plate 112 and the filter element 160 and only allows gas to exchange is formed, and there is no gap between the protection bellows 150 and the conducting rod 120, and only allows gas to pass through under the unsealed condition; the passage 1532 and the filter element 160 are arranged between the protective corrugated tube 150 and the transition plate 112, and metal particles inside the protective corrugated tube 150 can be blocked by the filter element 160 and cannot migrate to the outside of the protective corrugated tube 150, and in the structure, no other outlet or inlet exists, so that the metal particles inside the protective corrugated tube 150 can be ensured not to enter a main insulating cavity of the wall bushing 100 in the inflation and deflation process, and the operation reliability of the wall bushing 100 is ensured. Moreover, since the protection bellows 150 and the conductive rod 120 are fixedly connected and do not displace, when the conductive rod 120 deforms due to thermal expansion and cold contraction, the size of the protection bellows 150 changes accordingly to ensure that the conductive rod 120 does not bend or the transition plate 112 does not deform, so that the protection bellows 150 is adopted to mainly utilize the elastic deformation thereof to provide a deformation space for the conductive rod 120.

In the present embodiment, the head assembly 110 includes a transition tank 111 and a transition plate 112 connected to each other; the upper end of the transition tank 111 is provided with a first through hole 1111, and the lower end of the transition tank 111 is communicated with the first through hole 1111; the transition plate 112 is provided with a second through hole 1121, the conductive rod 120 passes through the first through hole 1111 and the second through hole 1121, and the transition tank 111 and the transition plate 112 are fixedly connected such that a receiving cavity 113 is formed in the transition tank 111 around the conductive rod 120. This wall bushing 100 simple structure, the core part is transition jar 111 and transition board 112, and the structure of traditional bellows has been replaced in transition jar 111's setting, as long as can guarantee that transition jar 111 seals up the setting, applys sealed measure in transition jar 111's outside promptly, can avoid adopting axial to move sealing device between transition jar 111 and the conducting rod 120, has improved product seal reliability greatly, can reduce manufacturing cost simultaneously. It should be noted that the sealing cover is provided with the head assembly 110 and the connecting terminal 140 of the conductive rod 120, as long as the electrical connection between the head assembly 110 and the conductive rod 120 is satisfied, the electrical connection may be direct contact, or may be internal conductor connection, and the shape and structure of the connecting terminal 140 are not particularly limited.

In other embodiments, the head assembly may be an integrally formed cavity structure, as long as the requirement of the rigid assembly is satisfied, that is, the head assembly does not deform and displace under the interference of the external heat condition. This has just guaranteed that head assembly can not take place deformation and displacement because of the length change of conducting rod, and then keeps wall bushing overall structure's stability.

In this embodiment, the upper surface of the transition plate 112 is provided with a convex ring 1123 around the second through hole 1121. The arrangement of the convex ring 1123 increases the supporting area of the conductive rod 120, and can improve the bending resistance of the conductive rod 120.

In this embodiment, the raised ring 1123 is disposed within the receiving cavity 113 of the head assembly 110 and does not exceed the height of the transition tank 111. That is, a gap exists between the upper end surface of the convex ring 1123 and the inner wall of the transition tank 111, and the gap is not in direct contact with the inner wall of the transition tank 111, so that the convex ring 1123 is not in contact with the inner wall of the transition tank 111 even if undergoing expansive deformation under the action of heat, the transition tank 111 is not deformed, and the reliability of the overall structure of the wall bushing 100 is ensured.

In other embodiments, the convex ring may also be disposed on the lower surface of the transition plate, or both the upper surface and the lower surface are provided with convex rings, which are essential to enlarge the contact area between the conductive rod and the transition plate and improve the bending resistance of the conductive rod.

In other embodiments, the transition plate may also be a planar plate, and the shape of the transition plate is not particularly limited.

In this embodiment, the transition tank 111 is a cylindrical tank, the upper end portion is provided with a first through hole 1111, the lower end portion penetrates through the transition tank to form a cylindrical cavity, and the first through hole 1111 communicates with the cylindrical cavity. The transition tank 111 is fixedly connected to the transition plate 112, and after the conductive rod 120 is inserted into the first through hole 1111 and the second through hole 1121, the annular cavity surrounding the conductive rod 120 forms an accommodating cavity 113.

In other embodiments, the transition tank may be non-cylindrical in shape, so long as it is adaptable to the connected components.

In this embodiment, a plurality of annular grooves 1112 are disposed around the sidewall of the conductor bar 120 within the transition tank 111. The annular groove 1112 serves as a particle trap to adsorb metal particles in the transition tank 111, and ensures stable electrical performance of the head of the wall bushing 100.

In the present embodiment, the number of the annular grooves 1112 is four. In other embodiments, the number of the annular grooves is not limited, and the specific number is reasonably designed according to the size of the inner wall of the transition tank. However, it is understood that the larger the number of the annular grooves, the denser the number of the annular grooves, the better the effect of adsorbing the metal particles.

In this embodiment, the annular groove 1112 is a rectangular groove, and in other embodiments, the annular groove may also be an arc groove or an irregular groove, and the shape is not limited specifically herein.

In this embodiment, the lower end portion of the transition tank 111 extends out of a first connection portion 1114 along the periphery of the transition tank 111, and the first connection portion 1114 is connected with the transition plate 112 in a sealing manner. The arrangement of the first connecting portion 1114 is convenient for fixedly connecting the transition tank 111 and the transition plate 112, and the sealing connection can ensure that the interior of the transition tank 111 is not invaded by moisture, so as to avoid influencing the electrical performance.

In the present embodiment, the transition plate 112 is provided with a first seal groove 1122, and a seal ring (not shown) is provided in the first seal groove 1122. In other embodiments, the first sealing groove may also be disposed on the first connecting portion, or both the first connecting portion and the transition plate are provided with sealing grooves, and the sealing ring is installed.

In this embodiment, the first connecting portion 1114 and the transition plate 112 are provided with corresponding through holes, and are fixedly connected by means of bolts (not shown). In other embodiments, the connection manner of the first connection portion and the transition plate may be glue, welding or a combination of the above fixing connection manners.

In the present embodiment, the portion of the conductive rod 120 located above the protection bellows 150 is a solid structure, and the portion of the conductive rod 120 located below the protection bellows 150 is a hollow structure. The solid conductive rod 120 portion can have good conductivity, and the hollow conductive rod 120 portion can reduce the weight of the conductive rod, thereby reducing the overall weight of the wall bushing 100 and reducing the cost.

In other embodiments, the conductive rod may be a full solid structure or a full hollow structure, the conductive rod is located at or above the protection bellows, and the hollow conductive rod may have a larger wall thickness.

In this embodiment, a threaded hole is formed in one surface of the flange 153, which is attached to the transition plate 112, a through hole corresponding to the threaded hole is formed in the transition plate 112, and the flange 153 and the transition plate 112 are in threaded connection through a bolt. The flange plate 153 is provided with a threaded hole on the surface attached to the transition plate 112, but the threaded hole is not provided on the transition plate 112, so that the assembly reason is considered, and the structure is more convenient to assemble. In this embodiment, the conductive rod 120 is provided with threads in the area below the transition plate 112, after the assembly of other components is completed, the second round nut 157 is sleeved on the head of the conductive rod 120 and screwed on the lower edge of the threaded area of the conductive rod 120, so as to prevent the nut from loosening due to vibration, the protection bellows 150 with the filter element 160 assembled is sleeved on the head of the conductive rod 120, the upper through hole 151 is located above, the lower through hole 152 is located below, the lower connection end 154 abuts against the second round nut 157, the first round nut 156 is sleeved on the head of the conductive rod 120 and screwed on the conductive rod 120, and the first round nut 156 abuts against the lower connection end 154, that is, the first round nut 156 and the second round nut 157 are clamped on both sides of the lower connection end 154 to fix the protection bellows 150 on the conductive rod 120, and then the transition plate 112 is sleeved on the head of the conductive rod 120, the through hole on the transition plate 112 corresponds to the threaded hole on the flange plate 153, and the transition plate 112 is fixedly connected with the flange plate 153 by adopting a bolt to penetrate through the through hole and be screwed into the threaded hole; then the transition tank 111 is sleeved from the head of the conducting rod 120 and is fixedly connected with the transition plate 112; and finally, fixedly connecting the wiring terminal 140 with the transition tank 111 to complete subsequent assembly. In the process, since the main body and the end portion of the conductive rod 120 are enclosed in the main insulating cavity, the bolt first passes through the flange 153 and then passes through the transition plate 112, so that the bolt connection has an obstacle to practical operation. Therefore, the connection structure in this embodiment is more convenient to assemble.

The wall bushing 100 of this embodiment is simple in structure, the head assembly 110 replaces the structure of a conventional corrugated pipe, an axial dynamic sealing device can be avoided, the sealing reliability of the product is greatly improved, the production cost can be reduced, the arrangement of the protective corrugated pipe 150 further prevents metal chips or other fragments which may be generated from entering the main insulation cavity of the wall bushing 100, and the operational reliability of the product is improved.

Example two:

as shown in fig. 4, the present embodiment provides a wall bushing 200, which is different from the first embodiment in that a non-metal liner 230 is added.

In this embodiment, the inner wall of the convex ring 2123 is provided with a non-metallic lining 230. The non-metal liner 230 prevents the conducting rod 220 from rubbing against the transition plate 212 and the transition tank 211 to generate metal chips, thereby improving the operational reliability of the product.

In this embodiment, the inner wall of the convex ring 2123 is provided with a plurality of grooves, and the non-metal liner 230 is embedded in the grooves. This structure can adopt the broken circle form with in the non-metal lining 230 embedding recess, non-metal lining 230 is the strip structure promptly, not whole circle structure, can be according to the length of the size adjustment non-metal lining 230 of recess, makes it imbed in the recess, easy to assemble and construct. In addition, the arrangement of the groove can reduce the using amount of the non-metal liner 230 and reduce the production cost; the nonmetal inner lining 230 of disconnected circle form imbeds that the groove inner wall compares and sets up in the bulge loop 2123 inner wall in the nonmetal inner lining whole piece of great area, and the installation of being more convenient for is fixed, and at the in-process that uses, the condition that nonmetal inner lining 230 takes place the displacement at bulge loop 2123 inner wall can not take place.

In other embodiments, the inner walls of the first through hole and the second through hole are provided with non-metal linings, so that metal particles generated by friction among the conducting rod, the transition plate and the transition tank are avoided, and the operation reliability of a product is improved.

In other embodiments, the non-metal lining may be disposed only on the inner wall of the first through hole or only on the inner wall of the second through hole.

In other embodiments, the non-metal liner may be continuously disposed in a contact region between the conductive rod and another metal conductor, so that a gap exists between the conductive rod and the other metal conductor, and generation of metal particles can be reduced or even avoided without contact.

In other embodiments, the non-metal lining may be fixed on the conductive rod, that is, the non-metal lining only needs to be fixedly connected with the conductive rod or any one of the inner wall of the first through hole, the inner wall of the second through hole, and the inner wall of the convex ring.

In this embodiment, the non-metallic liner 230 is a teflon liner. The polytetrafluoroethylene lining has good insulation and wear resistance, and also has good chemical corrosion resistance, and in the operation process of the wall bushing 200, if corrosive gas is generated due to electric arc, the polytetrafluoroethylene lining still can keep the performance thereof unaffected, and the nonmetal lining 230 is ensured to be not worn and continuously effective in the operation process of the wall bushing 200 to the maximum extent.

In other embodiments, if the gas generated by the arc of the insulating gas filled in the wall bushing is a non-corrosive gas or a less corrosive gas, the non-metallic lining may be any one of polyester lining or glass fiber lining, which have insulating and wear-resistant properties.

The wall bushing 200 of the present embodiment, due to the non-metal liner 230, can reduce or prevent the contact between the conductive rod 220 and other metal conductors, reduce the generation of metal particles, and improve the reliability of the product operation.

Example three:

as shown in fig. 5 to 6, the present embodiment provides a wall bushing 300, which is different from the second embodiment in the structure of the connection terminal 340 of the wall bushing 300 of the present embodiment.

In this embodiment, the connection terminal 340 sequentially includes a connection portion 341, a receiving portion 342, and a connecting portion 343, the receiving portion 342 is configured to receive an end portion of the conductive rod 320 and electrically connect with the conductive rod 320, and the connecting portion 343 is hermetically connected with an upper end portion of the transition tank 311. The terminal 340 is an electrical connection component of the wall bushing 300 for making electrical connections with other equipment. The connection portion 343 is provided to facilitate the fixed connection of the connection terminal 340 with the transition tank 341.

In the present embodiment, a second seal groove 314 is provided between the connection portion 343 of the terminal 340 and the upper end of the transition tank 311, a second seal ring (not shown) is provided in the second seal groove 314, and specifically, the second seal groove 314 is provided at the upper end of the transition tank 311. In other embodiments, the second seal groove may be provided at the connection portion, or both the connection portion and the upper end portion of the transition tank may be provided with a seal groove.

In this embodiment, the connecting portion 343 is provided with a through hole 3431, the upper end of the transition can 311 is correspondingly provided with a screw hole, and the connecting portion 343 and the transition can 311 are connected by a screw (not shown) passing through the through hole 3431 and screwed into the screw hole. In other embodiments, the connection manner of the connection part and the transition tank can be gluing, welding or a combination of the above fixing connection manners.

In the present embodiment, a spring finger 344 is disposed at an end of the conductive rod 320, the spring finger 344 abuts against an inner wall of the accommodating portion 342, and a gap 346 exists between the accommodating portion 342 and the end of the conductive rod 320 in an axial direction of the conductive rod 320. The spring contact fingers 344 are simultaneously in close contact with the inner wall of the accommodating portion 342 and the end of the conductive rod 320, so that the connection terminal 340 and the end of the conductive rod 320 have stable electrical connection, the head assembly can be maintained at the same potential, and the problem of head heating can be solved. A gap 346 exists between the end of the accommodating portion 342 and the end of the conductive rod 320 along the axial direction of the conductive rod 320, so that when the conductive rod 320 is axially deformed due to thermal expansion and cold contraction, the conductive rod 320 can be ensured to have a sufficient telescopic space, and the conductive rod 320 is prevented from being bent due to fixed connection or contact with the inner wall of the accommodating portion 342.

In this embodiment, the inner wall of the accommodating portion 342 is provided with a ring groove 345, the ring groove 345 accommodates the spring contact finger 344, and the spring contact finger 344 abuts against the inner wall of the accommodating portion 342, so that the accommodating portion 342 is electrically connected with the end of the conductive rod 320, the head assembly is kept at the same potential, and the problem of head heat generation is solved. In other embodiments, the accommodating portion may not have a ring groove therein, and a certain gap exists between the inner wall of the accommodating portion and the end of the conductive rod, so that the spring contact finger can be pressed between the inner wall of the accommodating portion and the conductive rod, and the spring contact finger can be maintained in a relatively fixed state.

The wall bushing 300 of this embodiment, because the structure of binding post 340 sets up ingeniously, satisfied the head of wall bushing 300 and possessed the requirement of electricity connection and equipotential, can guarantee that conducting rod 320 possesses abundant flexible space when conducting rod 320 takes place expend with heat and contract with cold's axial deformation simultaneously, avoid conducting rod 320 to take place the bending phenomenon because of fixed connection or with the inner wall contact of holding portion 342.

Example four:

as shown in fig. 7 to 8, the present embodiment provides a wall bushing 400, which is different from the third embodiment in that the wall bushing 400 further includes a hollow insulator 470.

In this embodiment, the wall bushing 400 further includes a hollow insulator 470, a flange 471 of the hollow insulator 470 is hermetically connected to the lower surface of the transition plate 412, and the conductive rod 420 penetrates through the hollow insulator 470. The hollow insulator 470 provides insulation protection for the inner conductor of the wall bushing 400.

In this embodiment, a third sealing groove 4711 is disposed between the flange 471 of the hollow insulator 470 and the transition plate 412, a third sealing ring (not shown) is disposed in the third sealing groove 4711, and specifically, the third sealing groove 4711 is disposed on the flange 471. In other embodiments, the third seal groove may be disposed on the lower surface of the transition plate, or both the flange and the lower surface of the transition plate may be provided with seal grooves.

In this embodiment, the head assembly 410 is provided with a pressure equalizing ball 480 at the periphery thereof, and the pressure equalizing ball 480 is fixedly connected with the head assembly 410. The function of the voltage equalizing ball 480 is to equalize voltage, ensuring that no abnormal corona discharge occurs in the head assembly 410 under the charged condition. The end of the wall bushing 400 is also similarly provided with a pressure equalizing ball.

In this embodiment, the conductive rod 420 is inserted into the hollow insulator 470 and fixedly connected to the end of the wall bushing 400, so as to ensure that the conductive rod 420 passing through the head assembly 410 will not displace when the conductive rod 420 expands with heat and contracts with cold.

In this embodiment, specifically, the wall bushing 400 has an overall structure that the conductive rod 420 is inserted into the hollow insulator 470 and fixedly connected to the end of the wall bushing 400, the conductive rod 420 only needs to pass through the head assembly 410, and the connection terminal 440 and the transition tank 411 are hermetically connected, so that the conductive rod 420 and the transition tank 411, and the conductive rod 420 and the transition plate 412 do not need to be fixedly and hermetically connected, and therefore, an axial dynamic sealing device can be prevented from being used between the transition tank 411 and the conductive rod 420, the sealing reliability of the product is greatly improved, and meanwhile, the bellows is omitted, so that the production cost can be reduced. And when the length of the conducting rod 420 changes due to thermal expansion and cold contraction, the tail end of the conducting rod 420 is fixed, and the head of the conducting rod 420 and the transition tank 411 can move axially relative to each other, at this time, because a gap 446 exists between the terminal 440 and the end of the conducting rod 420, the gap 446 provides a space for axial movement, and the conducting rod 420 cannot bend due to the increase of the length, so that the reliability of the product can be improved.

In the embodiment, due to the arrangement of the protection corrugated tube 450, a cavity which is formed by the protection corrugated tube 450, the conductive rod 420, the transition plate 412 and the filter element 460 and only allows gas to exchange is formed, and no gap exists between the protection corrugated tube 450 and the conductive rod 420, and only gas can pass through under the condition of no sealing; the passage and the filter element 460 are arranged between the protection corrugated pipe 450 and the transition plate 412, metal particles in the protection corrugated pipe 450 can be blocked by the filter element 460 and cannot migrate to the outside of the protection corrugated pipe 450, and in the structure, no other outlet or inlet exists, so that the metal particles in the protection corrugated pipe 450 can be prevented from entering the hollow insulator 470 of the wall bushing 400 in the air charging and discharging process, and the operation reliability of the wall bushing 400 is ensured. Moreover, since the protection bellows 450 and the conductive rod 420 are fixedly connected and do not move relative to each other, when the conductive rod 420 deforms due to thermal expansion and cold contraction, the size of the protection bellows 450 changes accordingly to ensure that the conductive rod 420 does not bend or the transition plate 412 does not deform, so that the protection bellows 450 is adopted to mainly change the elastic deformation thereof into a space for deformation of the conductive rod 420.

In this embodiment, the hollow insulator 470 is a composite insulator made of a composite material, and the composite insulator has light weight, low cost, and excellent insulating property and mechanical property. In other embodiments, the hollow insulator may be a porcelain insulator or the like made of other materials.

In this embodiment, the hollow insulator 470 is two sections of insulators, and the mounting structure 472 is disposed between the two sections of insulators, and the mounting structure 472 is used to mount the wall bushing 400 on a wall. That is, the wall bushing 400 includes a connection terminal 440, a transition tank 411, a transition plate 412, and a hollow insulator 470, which are connected in sequence, wherein the conductive rod 420 is inserted into the hollow insulator 470, an end of the conductive rod 420 is connected to the connection terminal 440, and a distal end of the conductive rod 420 is fixed to a distal end of the hollow insulator 470.

The wall bushing 400 may be installed at an oblique angle or horizontally along its axis. In the embodiment, the wall bushing 400 is installed obliquely, and the head of the wall bushing 400 is higher than the end of the wall bushing 400, in this case, metal particles existing in the transition tank 411 may fall into the annular groove 4112 due to the gravity, the annular groove 4112 serves as a particle trap to adsorb the metal particles in the transition tank 411, so that the metal particles are prevented from floating and migrating in the transition tank 411, and the electrical performance of the head of the wall bushing 400 is ensured to be stable.

The wall bushing has a simple structure, the head assembly replaces the structure of the traditional corrugated pipe, an axial dynamic sealing device can be avoided, the sealing reliability of the product is greatly improved, the production cost can be reduced, the arrangement of the protective corrugated pipe further prevents metal chips or other fragments which are possibly generated from entering the interior of the main insulating cavity of the wall bushing, and the operation reliability of the product is improved.

While the invention has been described with reference to the above disclosure and features, it will be understood by those skilled in the art that various changes and modifications in the above constructions and materials can be made, including combinations of features disclosed herein either individually or in any combination, as appropriate, without departing from the spirit of the invention. Such variations and/or combinations are within the skill of the art to which the invention pertains and are within the scope of the following claims.

Claims

1. A wall bushing, its characterized in that: the protective corrugated pipe comprises a head component, a conductive rod, a protective corrugated pipe and a wiring terminal;

the head assembly is provided with an accommodating cavity, the upper end part and the lower end part of the head assembly are respectively and coaxially provided with a first through hole and a second through hole which are communicated with the accommodating cavity,

the protective corrugated pipe is an annular shell which is communicated up and down, the protective corrugated pipe is respectively provided with an upper through hole and a lower through hole, the conducting rod penetrates through the first through hole, the second through hole, the upper through hole and the lower through hole, the protective corrugated pipe is provided with an upper connecting end around the upper through hole, the upper connecting end is fixedly connected with the lower end part of the head component around the second through hole, the lower through hole is fixedly connected with the conducting rod,

the wiring terminal is electrically connected with the conductive rod and is covered with the head component and the conductive rod in a sealing manner.

2. A wall bushing according to claim 1, wherein: the upper connecting end is a flange plate extending along the radial direction of the upper through hole, and the flange plate is attached to and fixedly connected with the lower end part of the head assembly.

3. A wall bushing according to claim 2, wherein: the flange plate is provided with a mounting hole, a channel communicated with the upper through hole is formed between the mounting hole and the upper through hole, the filter element is mounted in the mounting hole, and the filter element only supplies gas exchange between the inside of the protective corrugated pipe and the outside of the protective corrugated pipe.

4. A wall bushing according to claim 3, wherein: the filter element is of a metal net structure.

5. A wall bushing according to claim 1, wherein: the diameter of the lower through hole is smaller than the minimum inner diameter of the protection corrugated pipe, a lower connecting end is arranged around the lower through hole, a first round nut and a second round nut are arranged on two sides of the lower connecting end respectively, and the first round nut and the second round nut are connected with the conducting rod through threads respectively to clamp the lower connecting end so that the protection corrugated pipe is fixedly connected with the conducting rod.

6. A wall bushing according to claim 1, wherein: the head assembly comprises a transition tank and a transition plate which are connected with each other; the upper end part of the transition tank is provided with the first through hole, and the lower end part of the transition tank is communicated with the first through hole; the transition plate is provided with the second through hole, and the transition tank is fixedly connected with the transition plate, so that the conductive rod is surrounded in the transition tank to form the accommodating cavity.

7. A wall bushing according to claim 6, wherein: and a plurality of annular grooves are formed in the circumferential inner wall of the transition tank.

8. A wall bushing according to claim 6, wherein: the flange plate and the surface, which is attached to the transition plate, of the transition plate are provided with threaded holes, through holes corresponding to the threaded holes are formed in the transition plate, and the flange plate is in threaded connection with the transition plate through bolts.

9. A wall bushing according to claim 6, wherein: and a convex ring is arranged on the upper surface of the transition plate around the second through hole and is positioned in the accommodating cavity.

10. A wall bushing according to claim 9, wherein: and a non-metal lining is arranged on the inner wall of the first through hole and/or the inner wall of the second through hole and/or the inner wall of the convex ring.

11. A wall bushing according to claim 10, wherein: the inner wall of the convex ring is provided with a plurality of grooves, and the non-metal lining is embedded into the grooves.

12. A wall bushing according to claim 1, wherein: the wiring terminal sequentially comprises a wiring portion, an accommodating portion and a connecting portion, the accommodating portion is used for accommodating the end portion of the conductive rod and electrically connected with the conductive rod, and the connecting portion is connected with the upper end portion of the head assembly in a sealing mode.

13. A wall bushing according to claim 12, wherein: the end part of the conducting rod is provided with a spring contact finger which is abutted against the inner wall of the accommodating part, and a gap is formed between the accommodating part and the end part of the conducting rod along the axial direction of the conducting rod.

14. A wall bushing according to claim 1, wherein: the wall bushing further comprises a hollow insulator, the hollow insulator is connected with the transition plate in a sealing mode, and the conducting rod penetrates through the hollow insulator.