A high-pressure corrugated pipe made of dissimilar metals for high-voltage combined electric appliances

Abstract

The utility model provides a kind of dissimilar metal combined high-pressure bellows for high-voltage combined electric appliance, belong to bellows technical field, including bellows main body;Metal flanging part one and metal flanging part two are integrally formed in the both ends of the bellows main body respectively;Connecting flange one is equipped at the horizontal one side position of the metal flanging part one;Connecting flange two is equipped at the horizontal one side position of the metal flanging part two;Groove is respectively opened in the one side end face of the connecting flange one and connecting flange two, the metal flanging part one and metal flanging part two can be inserted in the inside of groove correspondingly;Support screw is respectively penetrated through the both sides of the connecting flange one and connecting flange two;The utility model has the advantages of high reliability, small thermal deformation influence, enhanced fatigue life, stable sealing performance etc.

Description

Technical Field

[0001] This utility model belongs to the field of corrugated pipe technology, specifically relating to a dissimilar metal composite high-voltage corrugated pipe for high-voltage combined electrical appliances. Background Technology

[0002] High-voltage switchgear has a wide range of applications in power systems due to its unique advantages. The reliability of the connection of its internal components directly affects the safe and stable operation of the entire power system. As a key component in high-voltage switchgear used to connect the shells of adjacent equipment, compensate for displacement, and adapt to deformation caused by factors such as thermal expansion and contraction, the performance of metal bellows is particularly important. During the operation of high-voltage switchgear, it will face various situations such as temperature changes and equipment foundation settlement. This requires the metal bellows to effectively compensate for these displacements while ensuring good sealing performance and mechanical strength.

[0003] Defects and shortcomings of existing technology:

[0004] 1. Welding defects: Traditional metal bellows and connecting parts (such as flanges) are usually connected by welding. Welding defects such as porosity, cracks, and incomplete penetration are prone to occur during the welding process. These defects will weaken the strength of the connection and reduce the sealing performance of the bellows. In the long-term operation, this may lead to gas leakage and affect the normal operation of high-voltage switchgear.

[0005] 2. Thermal Deformation Issues: The high heat generated during welding can cause thermal deformation of the bellows and connecting components. This thermal deformation may alter the bellows' geometry and dimensional accuracy, reducing its ability to compensate for displacement and negatively impacting sealing performance. Moreover, once thermal deformation occurs, it is difficult to completely eliminate it through subsequent adjustments, increasing product defect rates and production costs.

[0006] 3. Fatigue failure: During the operation of high-voltage combined electrical equipment, the bellows is constantly subjected to external forces such as displacement and vibration. Due to the structural design and stress distribution of traditional bellows, the working stress borne by each bellows is uneven, and some bellows bear excessive stress, which easily leads to fatigue cracks in these parts, eventually causing fatigue failure of the bellows. In some high-voltage equipment with frequent start-stop, the fatigue life of the bellows is significantly shortened, requiring frequent replacement, which increases the maintenance cost and downtime of the equipment.

[0007] 4. Unstable sealing performance: The sealing structure of existing bellows is often quite complex, and the sealing effect is affected by a variety of factors, such as welding quality, aging of sealing materials, and installation process. In actual operation, due to the combined effect of these factors, the sealing performance is prone to decline and air leakage occurs. Once air leakage occurs, it will not only affect the normal operation of high-voltage combined electrical appliances, but may also cause safety accidents.

[0008] Therefore, a high-voltage bellows with dissimilar metals for high-voltage combined electrical appliances is proposed. Utility Model Content

[0009] This utility model provides a dissimilar metal composite high-voltage bellows for high-voltage combined electrical appliances, the purpose of which is to solve the problems mentioned above.

[0010] This utility model provides a high-voltage bellows of dissimilar metal combination for high-voltage combined electrical appliances, including a bellows body; a metal flange portion one and a metal flange portion two integrally formed at both ends of the bellows body; a connecting flange portion one located on the horizontal side of the metal flange portion one; a connecting flange portion two located on the horizontal side of the metal flange portion two; grooves respectively formed on one end face of the connecting flange portion one and the connecting flange portion two, wherein the metal flange portion one and the metal flange portion two can be correspondingly embedded in the grooves; support screws respectively penetrating both sides of the connecting flange portion one and the connecting flange portion two; anti-loosening washers sleeved on the outer wall of the support screws; a locking nut and an anti-loosening nut screwed onto the outer wall of the support screws, wherein the locking nut is located on one side of the anti-loosening nut; a flexible conductive strip provided on the end face of the connecting flange portion one and the connecting flange portion two; and a sealing groove formed on one side wall of the connecting flange portion one and the connecting flange portion two, wherein a sealing ring is embedded in the sealing groove.

[0011] Furthermore, the flexible conductive strip includes a first crimp terminal, an intermediate flexible conductive strip, and a second crimp terminal. The first and second crimp terminals and the intermediate flexible conductive strip are formed by bending or hot pressing, and can be lengthened or shortened as the corrugated pipe body expands and contracts.

[0012] Furthermore, the end faces of the first metal flange and the first connecting flange and the second metal flange are flush with each other, and the end faces of the first metal flange and the second metal flange are machined to a Ra value not exceeding 3.2.

[0013] Furthermore, the first and second metal flanges are folded outwards, and the flanges are annular in shape, with an outer diameter slightly larger than the outer diameter of the corrugated pipe body and an inner diameter that matches the inner diameter of the corrugated pipe body.

[0014] Furthermore, both the first and second connecting flanges are provided with bolt holes, through which the support bolt passes.

[0015] Furthermore, the corrugated shape of the corrugated pipe body adopts a specially designed sine wave or trapezoidal wave.

[0016] Furthermore, the first connecting flange and the second connecting flange are square in shape and have chamfered edges.

[0017] Furthermore, the first and second metal flanges are arranged perpendicular to the corrugated pipe body and have rounded corners.

[0018] The beneficial effects of this utility model are as follows:

[0019] This utility model has the following advantages:

[0020] 1. High reliability: The combination of metal flange structure and crimp connection avoids the welding defects of traditional welding methods, greatly improving the reliability of the connection between the corrugated pipe and other components. Through bolt fastening and sealing gaskets, it can be ensured that the connection will not loosen or leak during long-term operation. In practical applications, after long-term operation tests, the corrugated pipe connection using this utility model structure did not have any loosening or leakage problems, while the corrugated pipe using traditional welding connection had varying degrees of connection problems.

[0021] 2. Minimal impact of thermal deformation: Because this invention uses a non-welding connection method, it avoids the impact of high heat generated during welding on the thermal deformation of the bellows and connecting components. This maintains the geometric shape and dimensional accuracy of the bellows, ensuring that its displacement compensation ability and sealing performance are not affected by thermal deformation. Bellows manufactured using this invention do not require additional thermal deformation correction processes, thus improving production efficiency. Since the bellows body and flange connection assembly are assembled, different materials can be used for processing. The flange connection assembly can use more economical materials such as carbon steel or aluminum alloy, thereby significantly reducing production costs.

[0022] 3. Enhanced fatigue life: The specially designed corrugated shape and optimized parameters make the stress distribution of the bellows more uniform when subjected to external forces, effectively reducing the generation of fatigue cracks and greatly improving the fatigue life of the bellows. In some high-voltage combined electrical appliance applications with frequent start-stop and large vibration, the bellows of this utility model can operate stably, reducing the replacement frequency and lowering equipment maintenance costs and downtime.

[0023] 4. Stable Sealing Performance: The sealing structure of this invention makes the bellows' sealing performance more stable and reliable. Under the action of compression force, the sealing ring can fully fill the sealing gap, with the compression rate controlled between 15% and 30%, effectively preventing gas leakage. Even in harsh environments such as high pressure and high temperature, it can maintain a good sealing effect. At the same time, the sealing gasket is more convenient to replace. When the sealing performance deteriorates, the sealing gasket can be replaced in time to restore the bellows' sealing performance.

[0024] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained by means of the structures particularly pointed out in the description and the drawings. Attached Figure Description

[0025] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0026] Figure 1 This is a schematic diagram of the structure of an embodiment of the present utility model;

[0027] Figure 2 This is a schematic diagram of the bellows elongation working state according to an embodiment of the present utility model;

[0028] Figure 3 This is a schematic diagram of the bellows shortening working state according to an embodiment of the present utility model;

[0029] Figure 4 This is a schematic diagram of the connecting flange structure according to an embodiment of the present utility model;

[0030] Figure 5 This is a schematic diagram of the corrugated pipe structure according to an embodiment of the present utility model;

[0031] Figure 6 This is a schematic diagram of the sealing ring and its compressed state according to an embodiment of the present invention;

[0032] Figure 7 This is a schematic diagram of the flexible conductive strip structure according to an embodiment of the present invention;

[0033] Reference numerals in the attached drawings: 1. Corrugated pipe body; 2. Metal flange one; 3. Metal flange two; 4. Connecting flange one; 5. Connecting flange two; 6. Support bolt; 7. Anti-loosening washer; 8. Locking nut; 9. Anti-loosening nut; 10. Flexible conductive strip; 11. Sealing ring; 71. Crimping terminal one; 72. Intermediate flexible conductive strip; 73. Crimping terminal two. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. The same reference numerals in the drawings represent the same components. It should be noted that the described embodiments are only some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the described embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0035] Reference Figure 1-7 This utility model provides a dissimilar metal composite high-voltage bellows for high-voltage combined electrical appliances, comprising:

[0036] Corrugated pipe body 1:

[0037] The corrugated pipe body 1 is made of high-quality metal material (usually stainless steel), which has good elasticity and mechanical strength and can effectively compensate for the displacement generated during the operation of high-voltage combined electrical appliances. The corrugated shape of the corrugated pipe body 1 adopts a specially designed sine wave or trapezoidal wave.

[0038] Metal flange part 1 (2) and metal flange part 2 (3):

[0039] Metal flange 1 2 and metal flange 2 3 are respectively provided at both ends of the corrugated pipe body 1. Metal flange 1 2 and metal flange 2 3 adopt an outward folding form. The shape of the flange is ring-shaped. Its outer diameter is slightly larger than the outer diameter of the corrugated pipe body 1, and its inner diameter is matched with the inner diameter of the corrugated pipe body 1. The width of the flange is designed according to the specifications and usage requirements of the corrugated pipe, and is generally between 15mm and 40mm.

[0040] Furthermore, the corrugated pipe body 1 and the metal flange part 1 and the metal flange part 2 are formed by rolling of single or multiple layers of high-quality metal sheets using a mold. The metal flange part 1 and the metal flange part 2 are arranged perpendicularly to the corrugated pipe body 1 with rounded corners. The flange size D is 15mm to 40mm. The metal flange part 1 and the metal flange part 2 are integrally formed with the corrugated pipe body 1 through cold stamping or hot extrusion processes. The cold stamping process is suitable for metal materials with softer materials and thinner thickness, which can ensure the dimensional accuracy and surface quality of the flange. The hot extrusion process is suitable for metal materials with harder materials and thicker thickness. By extruding the metal material at high temperature, the flange and the corrugated pipe body 1 are better integrated, and the connection strength is improved. In the cold stamping process, the stamping pressure is controlled at 3 to 5 MPa, which can make the flange uniformly formed without obvious deformation and cracks.

[0041] Furthermore, in order to improve the corrosion resistance and sealing performance of the metal flange part 1 2 and the metal flange part 2 3, the surface of the flange is specially treated by means of electroplating, spraying or chemical plating to form a corrosion-resistant protective film on the flange surface. At the same time, the sealing surface of the flange is polished so that its surface roughness Ra value is no greater than 3.2μm, so as to improve the sealing effect.

[0042] Connecting flange 1 (4) and connecting flange 2 (5):

[0043] Among them, connecting flange 1 4 and connecting flange 2 5 are located between metal flange 1 2 and metal flange 2 3. The end faces of connecting flange 1 4 and connecting flange 2 5 are provided with grooves, which can embed metal flange 1 2 and metal flange 2 3 into the grooves. After being embedded, metal flange 1 2 is flush with the end faces of connecting flange 1 4 and metal flange 2 3 and connecting flange 2 5, and the end faces of metal flange 1 2 and metal flange 2 3 are machined to a Ra value not exceeding 3.2.

[0044] Furthermore, the connecting flange 4 and the connecting flange 5 are square in shape with chamfered edges and openings 41 and 42 on their end faces. The bellows body 1 is connected to other components of the high-voltage combined electrical appliance (such as equipment housing, pipes, etc.) through the openings 42 on the connecting flange 4 and the connecting flange 5.

[0045] Support screw 6:

[0046] Bolt holes are provided on both connecting flange 4 and connecting flange 5. Support bolts 6 pass through the bolt holes and are respectively inserted on both sides of connecting flange 4 and connecting flange 5. Anti-loosening washers 7, lock nuts 8, and anti-loosening nuts 9 are respectively installed on the support bolts 6 on both sides of connecting flange 4 and connecting flange 5. The entire bellows section can be equipped with 4 or 8 support bolts 6 to play a role in stabilization, support, and guiding of expansion and contraction.

[0047] Furthermore, depending on the operating conditions, an appropriate gap A is left on the right side of connecting flange 2 5. The extension of the busbar equipment can be achieved by leaving gap A, and an appropriate gap B is left on the left side of connecting flange 2 5. The shortening of the busbar equipment can be achieved by leaving gap B. Anti-loosening washers 7, lock nuts 8, and anti-loosening nuts 9 are then installed in sequence. Connecting flange 1 4 and connecting flange 2 5 are respectively connected to the busbar of the high-voltage combined electrical equipment. By selectively leaving gaps on the left or right side of the movable flange, the expansion and contraction of the busbar equipment can be achieved, thereby absorbing the axial error and radial deviation caused by the processing and installation of the equipment, as well as the expansion and contraction of the busbar caused by thermal expansion and contraction.

[0048] Furthermore, there are 4 to 8 support screws 6. The support screws 6 pass through the flange connection components on both sides through the opening 41, and are combined with the anti-loosening washer 7, locking nut 8, and anti-loosening nut 9 to play a role in stabilizing, supporting and guiding the telescopic movement.

[0049] Flexible conductive busbar 10:

[0050] Flexible conductive busbar 10 is installed on the end faces of connecting flange 1 4 and connecting flange 2 5 to ensure the conductive continuity of the flanges on both sides when the expansion joint is working, and to enable the normal flow of short-circuit current.

[0051] Furthermore, the flexible conductive part includes a first crimp terminal 71, an intermediate flexible conductive strip 72, and a second crimp terminal 73. The first crimp terminal 71 and the second crimp terminal 73, together with the intermediate flexible conductive strip 72, are produced by bending or hot pressing, and can be extended or shortened as the corrugated pipe body 1 expands and contracts.

[0052] Sealing ring 11:

[0053] A sealing groove is provided on the end face of the busbar housing flange that is in contact with the high-voltage combined electrical appliance, connecting flange 4 and connecting flange 5. The sealing ring 11 can be installed in the sealing groove. The sealing ring 11 is deformed by compression to achieve sealing. The sealing ring 11 is made of rubber. The ring diameter in the free state is E. After being installed and deformed, the ring height is F. The compression rate (EF) / E×100% of the sealing ring 11 is between 15% and 30%.

[0054] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A high-voltage bellows of dissimilar metal composite type for high-voltage combined electrical appliances, characterized in that: Including the corrugated pipe body (1); Metal flange part one (2) and metal flange part two (3) are integrally formed at both ends of the corrugated pipe body (1). A connecting flange (4) is provided at the horizontal side of the metal flange (2); A connecting flange 2 (5) is provided at the horizontal side of the metal flange 2 (3); Grooves are respectively opened on one end face of the connecting flange one (4) and the connecting flange two (5), and the metal flange one (2) and the metal flange two (3) can be correspondingly embedded in the inside of the groove; Support bolts (6) pass through both sides of the connecting flange one (4) and connecting flange two (5); Anti-loosening washer (7) sleeved on the outer wall of the support screw (6); The locking nut (8) and the anti-loosening nut (9) are screwed onto the outer wall of the support screw (6), with the locking nut (8) located on one side of the anti-loosening nut (9); Flexible conductive strips (10) are provided on the end faces of the connecting flange one (4) and the connecting flange two (5). A sealing groove is formed on one side wall of the connecting flange one (4) and the connecting flange two (5), and a sealing ring (11) is embedded in the sealing groove.

2. The high-voltage bellows of dissimilar metal combination type for high-voltage combined electrical appliances according to claim 1, characterized in that: The flexible conductive strip (10) includes a first crimp terminal (71), an intermediate flexible conductive strip (72) and a second crimp terminal (73). The first crimp terminal (71) and the second crimp terminal (73) and the intermediate flexible conductive strip (72) are made by bending or hot pressing, and can be stretched or shortened with the expansion and contraction of the corrugated pipe body (1).

3. The high-voltage bellows of dissimilar metal combination type for high-voltage combined electrical appliances according to claim 1, characterized in that: The end faces of the metal flange part one (2) that contact the connecting flange part one (4) and the metal flange part two (3) that contact the connecting flange part two (5) are flush, and the end faces of the metal flange part one (2) and the metal flange part two (3) are machined to a Ra value not exceeding 3.

2.

4. The high-voltage bellows of dissimilar metal combination type for high-voltage combined electrical appliances according to claim 1, characterized in that: The metal flange part one (2) and the metal flange part two (3) are folded outwards. The flange is ring-shaped, with its outer diameter slightly larger than the outer diameter of the corrugated pipe body (1) and its inner diameter matching the inner diameter of the corrugated pipe body (1).

5. A high-voltage bellows of dissimilar metal composite type for high-voltage combined electrical appliances according to claim 1, characterized in that: Bolt holes are provided on both the first connecting flange (4) and the second connecting flange (5), and the support screw (6) passes through the bolt holes.

6. A high-voltage bellows of dissimilar metal composite type for high-voltage combined electrical appliances according to claim 1, characterized in that: The connecting flange one (4) and connecting flange two (5) are square in shape and have chamfered edges.

7. A high-voltage bellows of dissimilar metal composite type for high-voltage combined electrical appliances according to claim 1, characterized in that: The metal flange part one (2) and the metal flange part two (3) are arranged perpendicularly to the corrugated pipe body (1) with rounded corners.

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