Sleeve bottom sealing structure with oil return path
By using a combined sealing structure of raw tape and sealing ring at the bottom of the oil-paper capacitor transformer bushing, the problems of laborious installation and high precision of parts are solved, convenient assembly and effective oil return are achieved, and the partial discharge performance of the bushing is improved.
Patent Information
- Application Number
- CN202422829258.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-20
- Publication Date
- 2025-09-23
- Estimated Expiration
- 2034-11-20
AI Technical Summary
The bottom sealing structure of the existing oil-paper capacitor transformer bushing is laborious to install, and requires high parts processing accuracy and fit, resulting in great assembly difficulty and a lack of an effective oil return path.
Use raw tape and sealing ring to complete the sealing on the conductive pipe thread. Combined with the base design with an oil return path, the sealing is achieved using polytetrafluoroethylene raw tape and sealing ring. The base is equipped with an oil outlet and an oil return channel, which is extruded and sealed with a locking nut and sealing ring.
It saves assembly effort and reduces the difficulty of parts processing and assembly. At the same time, it meets the oil return requirements of the transformer, can effectively clean impurities inside the bushing, and improve partial discharge performance.
Smart Images
Figure CN223378012U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a bushing bottom sealing structure with an oil return path, belonging to the technical field of transformer bushings. Background Art
[0002] The bottom conductive tube of an oil-paper capacitor transformer bushing often uses multiple O-rings for axial sealing. This installation requires pushing multiple O-rings onto the conductive tube, which is laborious. Furthermore, this axial sealing method requires high component machining precision and a high degree of fit between components, making both component machining and bushing assembly difficult. Utility Model Content
[0003] The purpose of the utility model is to provide a casing bottom sealing structure with an oil return path, which uses raw tape and a sealing ring to complete the sealing on the conductive pipe thread, and is easy to assemble and saves effort; at the same time, the base is provided with an oil return path to meet the oil return needs of the casing.
[0004] In order to achieve the above-mentioned purpose, the technical solution adopted by the present utility model is:
[0005] A bushing bottom sealing structure with an oil return path comprises a lower porcelain bushing and a conductive tube coaxially arranged in the lower porcelain bushing, wherein an oil passage is formed between the conductive tube and the lower porcelain bushing;
[0006] The bottom of the conductive tube extends to below the lower porcelain sleeve and a raw tape is wrapped around the bottom of the conductive tube;
[0007] A base is screwed onto the bottom of the conductive tube, and a first sealing ring is embedded in the upper end surface of the base. The base squeezes the first sealing ring so that the first sealing ring abuts against the bottom end of the lower porcelain sleeve.
[0008] An oil outlet is provided on the base, and an oil return passage connecting the oil outlet and the oil passage is formed in the base; an oil plug is screwed in the oil outlet.
[0009] Preferably, the raw tape is made of polytetrafluoroethylene.
[0010] Preferably, a second sealing ring is provided at the abutting surface between the oil plug and the oil outlet, and the second sealing ring is sleeved on the oil plug.
[0011] Preferably, a locking nut is screwed onto the conductive tube below the base, and a third sealing ring is sleeved onto the conductive tube above the locking nut.
[0012] The locking nut squeezes the third sealing ring so that the third sealing ring abuts against the lower end surface of the base.
[0013] Preferably, a pressure equalizing ball is also installed on the conductive tube below the locking nut.
[0014] The beneficial effects of the present invention are:
[0015] By using polytetrafluoroethylene raw tape and sealing rings on the conductive pipe threads to achieve sealing, assembly is convenient and labor-saving. At the same time, the base is equipped with an oil return path to meet the oil return requirements of the bushing. In this way, transformer oil enters the bushing through the oil inlet at the bushing head and can flow out into the bushing oil immersion system through the oil flow channel, oil return channel, and oil return port. The bushing can then be treated by oil return to remove impurities such as dust, metal particles, and paper fibers inside the bushing, reducing local discharge and improving bushing quality. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 Schematic diagram of the casing bottom sealing structure;
[0017] Figure 2 This is a diagram showing the locations of the oil inlet and outlet ports of the oil-paper capacitor transformer bushing.
[0018] The main reference numerals in the figures have the following meanings:
[0019] 1. Lower porcelain sleeve, 2. Conductive tube, 3. Oil channel, 4. Raw material tape, 5. Base, 6. First sealing ring, 7. Oil outlet, 8. Oil return channel, 9. Oil plug, 10. Second sealing ring, 11. Locking nut, 12. Third sealing ring, 13. Pressure equalizing ball. DETAILED DESCRIPTION
[0020] The present invention will be described in detail below with reference to the accompanying drawings and embodiments.
[0021] This embodiment provides a casing bottom sealing structure with an oil return path, see Figure 1 As shown, the assembly comprises a lower porcelain sleeve 1 and a conductive tube 2 coaxially disposed within the lower porcelain sleeve 1, with an oil passage 3 formed between the conductive tube 2 and the lower porcelain sleeve 1. The bottom of the conductive tube 2 extends below the lower porcelain sleeve 1 and is wrapped with polytetrafluoroethylene (PTFE) tape 4. A base 5 is screwed onto the bottom of the conductive tube 2. The upper end surface of the base 5 defines a sealing groove, within which a first sealing ring 6 is embedded. When the base 5 is screwed onto the bottom of the conductive tube 2 wrapped with the polytetrafluoroethylene (PTFE) tape 4, it compresses the first sealing ring 6, causing it to tightly abut the bottom end of the lower porcelain sleeve 1.
[0022] At the same time, an oil outlet 7 is formed on the base 5, and an oil return channel 8 is formed in the base 5, connecting the oil outlet 7 with the oil flow channel 3. An oil plug 9 is screwed into the oil outlet 7. A second sealing ring 10 is provided at the abutment surface between the oil plug 9 and the oil outlet 7, and the second sealing ring 10 is sleeved on the oil plug 9.
[0023] Furthermore, a locking nut 11 is screwed onto the conductive tube 2 wrapped with the polytetrafluoroethylene raw tape 4 located below the base 5, and a third sealing ring 12 is sleeved on the conductive tube 2 located above the locking nut 11; the locking nut 11 squeezes the third sealing ring 12 so that the third sealing ring 12 abuts against the lower end surface of the base 5.
[0024] See also Figure 2 As shown, the bushing head has an oil inlet that provides transformer oil into the bushing, that is, into the oil passage 3. Transformer oil enters the bushing cavity through the head oil inlet and is discharged through the oil return port, thereby repeatedly flushing the bushing cavity and internal components, clearing impurities from the bushing and improving the bushing's partial discharge performance. After the bushing oil return process is completed, the oil return port is sealed with an oil plug 9 and a second sealing ring 10.
[0025] After the oil return process is completed, the pressure equalizing ball 13 is installed on the conductive tube 2 wrapped with the polytetrafluoroethylene raw tape 4 below the locking nut 11.
[0026] The above is only a preferred embodiment of the present utility model patent. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present utility model patent. These improvements and modifications should also be regarded as the scope of protection of the present utility model patent.
Claims
1. A casing bottom sealing structure with an oil return path, characterized in that: It includes a lower porcelain sleeve and a conductive tube coaxially arranged in the lower porcelain sleeve, and an oil passage is formed between the conductive tube and the lower porcelain sleeve; The bottom of the conductive tube extends to below the lower porcelain sleeve and a raw tape is wrapped around the bottom of the conductive tube; A base is provided at the bottom of the conductive tube, and a first sealing ring is embedded in the upper end surface of the base. The base squeezes the first sealing ring so that the first sealing ring abuts against the bottom end of the lower porcelain sleeve. An oil outlet is provided on the base, and an oil return passage connecting the oil outlet and the oil passage is formed in the base; an oil plug is screwed in the oil outlet.
2. The casing bottom sealing structure with oil return path according to claim 1, characterized in that: The raw tape is made of polytetrafluoroethylene.
3. The casing bottom sealing structure with oil return path according to claim 1, characterized in that: A second sealing ring is provided at the abutting surface between the oil plug and the oil outlet, and the second sealing ring is sleeved on the oil plug.
4. The casing bottom sealing structure with an oil return path according to claim 1, characterized in that: A locking nut is screwed onto the conductive tube below the base, and a third sealing ring is sleeved onto the conductive tube above the locking nut. The locking nut squeezes the third sealing ring so that the third sealing ring abuts against the lower end surface of the base.
5. The casing bottom sealing structure with oil return path according to claim 4, characterized in that: A pressure equalizing ball is also installed on the conductive tube below the locking nut.