Sleeve ascending flanged base capable of preventing air clog
By installing a rubber ring on the lower surface of the bushing riser flange, the problem of air pockets in the bushing riser was solved, enabling the transformer to operate safely and stably, simplifying the installation process and reducing costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-20
- Publication Date
- 2026-03-13
AI Technical Summary
The existing bushing riser structure cannot effectively expel the gas generated during transformer operation, leading to gas entrapment and affecting the transformer's insulation performance and normal operation.
A rubber ring is installed on the lower surface of the sleeve riser flange. The elasticity and adaptability of the rubber ring fill the cavity between the sleeve and the riser, reducing gas accumulation. The problem of gas buildup can be solved by quickly installing the rubber ring during power outage maintenance.
It effectively prevents gas buildup, ensuring the long-term safe and stable operation of the transformer. It is also simple to install, low in cost, and does not require changes to the original gas duct design.
Smart Images
Figure CN121662558A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of transformer equipment technology, and specifically relates to a bushing riser to prevent air leakage. Background Technology
[0002] The bushing riser is an important component of a power transformer, serving as a crucial connection between the transformer tank and the bushing. Its main function is to support the bushing and provide internal and external insulation. The bushing riser is installed on the upper part of the transformer tank cover. The top flange of the riser connects to the bushing, and the bottom of the riser communicates with the transformer tank.
[0003] During transformer operation, internal insulating materials such as transformer oil and cardboard undergo partial decomposition due to electrical, thermal, and mechanical stress, generating gas. This phenomenon can occur during normal aging processes as well as during slow or rapid faults. Regardless of the process, the transformer design must ensure rapid gas removal to prevent gas accumulation inside the transformer. If excessive gas accumulates and cannot be removed promptly, it can reduce the transformer's insulation performance, affect the rheological properties of the transformer oil, reduce oil cooling, and cause abnormal oil levels, ultimately impacting the transformer's normal operation.
[0004] Because the bushing riser is installed on the upper part of the transformer tank cover, gases generated during transformer operation can easily accumulate inside the riser. Therefore, a vent pipe is usually installed on the upper part of the riser to discharge the gases generated during transformer operation and ensure safe operation. However, currently used riser structures have certain defects and cannot completely discharge the gases inside, resulting in some gas trapping. On the one hand, due to structural limitations, the vent hole connecting to the vent pipe cannot be designed to reach the highest point of the riser (the highest point has a top flange on the bushing); on the other hand, even if the riser manufacturer designs a sealed vent hole on the top flange of the bushing, personnel are not allowed to climb up or operate the transformer while it is energized during operation, so the vent hole cannot be manually opened during operation, and the gases cannot be discharged in a timely manner.
[0005] In summary, a quick and effective technical solution is needed to address the technical problem of this casing raising seat gas. Summary of the Invention
[0006] To solve the above-mentioned technical problems, the present invention provides a sleeve riser to prevent air leakage. The technical solution adopted by the present invention is as follows: A casing riser seat for preventing air leakage includes a riser seat wall and an upper riser seat flange and a lower riser seat flange located at both ends of the riser seat wall. A circular hole is opened at the center of the upper riser seat flange. Four mounting threaded holes are evenly distributed on the lower surface of the casing flange at the lower end of the casing. The rubber ring is composed of two semi-circular rubber rings joined together. Each semi-circular rubber ring has two through holes corresponding to the mounting threaded holes. The rubber ring has the same thickness as the upper riser seat flange. The inner diameter of the rubber ring is the same as the outer diameter of the oil end of the casing. The outer diameter of the rubber ring is the same as the inner diameter of the circular hole of the upper riser seat flange. Blackened bolts pass through the through holes and are screwed into the mounting threaded holes of the casing flange.
[0007] Preferably, a flat washer and a spring washer are installed on the threaded rod between the bolt head of the blackened bolt and the rubber ring, with the flat washer positioned above the spring washer.
[0008] Preferably, the outer diameter side of the rubber ring has a constricted structure.
[0009] Preferably, the rubber ring is made of nitrile rubber, acrylate, or fluorosilicone rubber.
[0010] The present invention has the following advantages: By designing and installing rubber rings of appropriate specifications on the lower surface of the bushing riser flange, the air-collecting cavity formed between the bushing and the bushing riser is filled, reducing the accumulation of gas during transformer operation and thus overcoming the defect of air pocketing in the bushing riser. This invention has the advantages of simple processing and manufacturing, convenient installation, and low cost. It does not require changes to the original vent pipe design or welding structure and can effectively solve the problem of air pocketing in the bushing riser. At the same time, for transformers in operation, rubber rings can be quickly installed by technically modifying the drilled holes of the bushing flange during power outages and maintenance, ensuring the long-term safe and stable operation of the transformer. Attached Figure Description
[0011] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of a commonly used sleeve riser structure. Figure 2 This is a schematic diagram of a commonly used sleeve riser structure two; Figure 3 This is a schematic diagram of the structure of the sleeve riser for preventing air pockets according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the design and installation of the rubber ring according to an embodiment of the present invention; Figure 5This is a schematic diagram of the structure of the rubber ring according to an embodiment of the present invention, wherein part 5a is a schematic diagram of the two semi-circular rubber rings in a split state, and part 5b is a schematic diagram of the two semi-circular rubber rings in a spliced state. In the diagram, 1-Bucket; 2-Bucket flange; 3-Upper flange of riser seat; 4-Riser seat cylinder wall; 5-Bucket oil end; 6-Equalizing ball of bushing oil end; 7-Lower flange of riser seat; 8-Cavity; 9-Air duct; 10-Air vent plug of bushing flange; 11-Air duct channel of bushing flange; 12-Rubber ring; 13-Flat washer; 14-Spring washer; 15-Blackened bolt; 16-Through hole; 17-Bias line of rubber ring; 18-Transformer oil. Detailed Implementation
[0012] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.
[0013] The commonly used sleeve riser structures in the industry are shown in the attached figure. Figure 1 , 2 As shown. (Attached) Figure 1 In the existing bushing riser structure shown, bushing 1 is mounted on upper flange 3 of the riser via lower bushing flange 2. Upper flange 3 is fixedly located on the upper part of riser cylinder wall 4, and lower flange 7 is fixedly located on the lower part of riser cylinder wall 4. A circular hole is opened at the center of upper flange 3 to allow the bushing oil end equalizing ball 6 and bushing oil end 5 of bushing 1 to pass smoothly. Therefore, the diameter of the circular hole in upper flange 3 must be larger than the diameters of bushing oil end equalizing ball 6 and bushing oil end 5, with a certain margin. Normally, the diameter of bushing oil end equalizing ball 6 is larger than the diameter of bushing oil end 5. Therefore, when the top plane of transformer oil 18 is flush with the lower surface of upper flange 3, a cavity 8 is formed between the circular hole in upper flange 3 and the bushing oil end 5 and the top plane of transformer oil 18. Since the vent pipe 9 is usually designed between the lower side surface of upper flange 3 and riser cylinder wall 4, the gas accumulated in cavity 8 cannot be discharged through vent pipe 9. Moreover, even if the gas duct 9 is designed on the upper surface of the flange 3 on the riser seat, it is still impossible to vent the gas in the cavity 8.
[0014] Appendix Figure 2 The existing sleeve riser structure II shown has the same overall structural principle as the attached diagram. Figure 1Compared to structure one, this structure features a specially designed bushing flange venting channel 11 and a bushing flange vent plug 10 on the bushing flange 2. The bushing flange venting channel 11 connects to the cavity 8. Although this structure can vent the gas accumulated in the cavity 8, the vent plug 10 can only be manually operated to release the gas when the transformer is de-energized. During transformer operation, it is neither permissible nor possible for personnel to climb onto the transformer for live operation, so the gas cannot be released in a timely manner. Therefore, both of the commonly used bushing riser structures in the industry have inherent defects.
[0015] The present invention provides a sleeve riser for preventing air leakage, the structure of which is shown in the attached figure. Figure 3 , 4 As shown in Figure 5, four mounting threaded holes are pre-drilled on the lower surface of the sleeve flange 2 of the sleeve 1. Simultaneously, a rubber ring 12 is designed. The thickness of the rubber ring 12 is the same as the thickness of the flange 3 on the riser seat, meaning the rubber ring 12 can fill the cavity 8 in the thickness direction. The inner diameter of the rubber ring 12 is the same as the outer diameter of the sleeve oil end 5, so that the inner wall of the rubber ring 12 fits against the outer wall of the sleeve oil end 5. The outer diameter of the rubber ring 12 is the same as the inner diameter of the circular hole of the flange 3 on the riser seat, so that the outer wall of the rubber ring 12 fits against the inner wall of the circular hole of the flange 3 on the riser seat, meaning the rubber ring 12 can fill the cavity 8 in the horizontal direction. (See attached figure.) Figure 5 As shown, the rubber ring 12 is designed as two semi-circular rubber rings, and the junction of the two semi-circular rubber rings forms a split line 17. Each semi-circular rubber ring has two through holes 16 corresponding to the mounting thread holes. The rubber ring 12 is fixed by passing the blackened bolt 15 through the through holes 16 and screwing it into the four mounting thread holes on the lower surface of the sleeve flange 2. A flat washer 13 and a spring washer 14 are installed on the threaded rod between the bolt head of the blackened bolt 15 and the rubber ring 12, with the flat washer 13 positioned above the spring washer 14. The rubber ring 12 is designed with a split structure because the diameter of the equalizing ball 6 at the sleeve oil end is larger than the diameter of the sleeve oil end 5. Without the split structure, the rubber ring 12 cannot pass through the equalizing ball 6 and be installed onto the sleeve flange 2. After the rubber ring 12 is installed onto the lower surface of the sleeve flange 2, the sleeve 1 is installed onto the upper flange 3 of the riser according to the normal production process.
[0016] It should be noted that the rubber ring 12 can be made of materials with good compatibility with transformer oil 18, such as nitrile rubber, acrylic rubber, or fluorosilicone rubber. Because the rubber ring 12 is made of rubber, it has good elasticity. Therefore, when the bushing 1 is installed on the flange 3 of the riser seat, it can prevent the root of the bushing oil end 5 from colliding with the opening of the flange 3 of the riser seat. It also makes it easier for the rubber ring 12 to be "squeezed" into the round hole of the flange 3 of the riser seat, thereby reducing the volume of the cavity 8.
[0017] Additionally, as attached Figure 3 , 4As shown in Figure 5, the vertical cross-section of the rubber ring 12 is not rectangular, but designed as a cone, i.e., the outer diameter side is tapered. This makes it easier for the rubber ring 12 to fall into the circular hole of the flange 3 on the riser seat, and its position is less likely to shift. Although the tapered design of the rubber ring 12 still forms a small cavity 8, this cavity 8 is negligible compared to the volume before the structural improvement. Even if gas accumulates here, the amount of gas is negligible and has no impact on the operation of the transformer. In addition, the flat washer 13, spring washer 14, and blackened bolt 15 only serve to fix the rubber ring 12. Since the rubber ring 12 is lightweight, the flat washer 13, spring washer 14, and blackened bolt 15 only need to be M4 or M6. This satisfies the requirement of fixing the rubber ring 12 and avoids interference with the inner edge of the opening of the flange 3 on the riser seat, ensuring soft contact between the rubber ring 12 and the flange 3 on the riser seat.
[0018] In the past, the design of sleeve riser structures in the industry has focused on how to better vent air. The embodiments of this invention take a different approach, studying how to eliminate the cavity 8 that traps air inside the sleeve riser, thus solving the root cause of air trapping and making the prevention of air trapping more effective.
[0019] In the embodiments of the present invention, all technical features not described in detail are existing technologies or conventional technical means, and will not be repeated here.
[0020] Finally, it should be noted that the above embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit them. The scope of protection of the present invention is not limited thereto. Those skilled in the art should understand that any person skilled in the art can modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention.
Claims
1. A sleeve riser seat for preventing air leakage, comprising a riser seat cylinder wall (4) and a riser seat upper flange (3) and a riser seat lower flange (7) located at both ends of the riser seat cylinder wall (4), wherein a circular hole is formed at the center of the riser seat upper flange (3), characterized in that, Four mounting screw holes are evenly distributed on the lower surface of the sleeve flange (2) at the lower end of the sleeve (1). The rubber ring (12) is composed of two semi-circular rubber rings joined together. Each semi-circular rubber ring has two through holes (16) corresponding to the mounting screw holes. The rubber ring (12) has the same thickness as the flange (3) on the riser seat. The inner diameter of the rubber ring (12) is the same as the outer diameter of the sleeve oil end (5). The outer diameter of the rubber ring (12) is the same as the inner diameter of the round hole on the flange (3) on the riser seat. The blackened bolt (15) passes through the through hole (16) and is screwed into the mounting screw hole of the sleeve flange (2).
2. The sleeve riser for preventing air leakage according to claim 1, characterized in that, A flat washer (13) and a spring washer (14) are installed on the thread between the bolt head of the blackened bolt (15) and the rubber ring (12), with the flat washer (13) located above the spring washer (14).
3. A sleeve riser for preventing air leakage according to claim 2, characterized in that, The outer diameter side of the rubber ring (12) has a closed structure.
4. A sleeve riser for preventing air leakage according to claim 3, characterized in that, The rubber ring (12) is made of nitrile rubber, acrylate, or fluorosilicone rubber.