| Brand | Switchgear parts |
| Model NO. | 66-138 kV intermediate insulation, direct connection (reinforced waterproof type) |
| Rated voltage | 138kV |
| Series | YJJJI |
Name and Model
Integrated prefabricated insulation joint YJJJI
Integrated prefabricated straight joint YJJTI
1.Product definition and classification
Intermediate insulation joint: used for electrically disconnecting cable metal sheaths, grounding shields, and insulation shields, suitable for scenarios that require segmented grounding
Intermediate direct connector: maintains electrical continuity between the metal sheath and shielding layer, suitable for continuous connection of long-distance cables
Both belong to high-voltage prefabricated joints, with voltage levels covering 66-138 kV. They use integral prefabricated rubber insulation components, mostly made of imported silicone rubber, with excellent sealing and insulation performance
2. Characteristics of Waterproof Technology
Built in core water blocking solution: such as 3M's 578 # water blocking material, it can radially seal the moisture in the core and still pass long-term live testing under 1 meter water pressure
Multi layer waterproof structure: using 2228 # waterproof tape as the main waterproof layer, its self melting characteristics can form a shell shaped waterproof layer, which has been verified through long-term immersion tests
Cold shrink terminal sealing: The third-generation cold shrink technology forms an adaptive seal through silicone rubber mud and cold shrink pressure, adapting to extreme environments
3. Performance requirements
Electrical performance: The insulation resistance shall not be less than 100m Ω at room temperature, and the withstand voltage test shall be 1.5 times the rated voltage (for 1 hour)
Mechanical properties: The tensile strength of the outer sheath is ≥ 12MPa, and the elongation at break is ≥ 300%
Sealing: It needs to withstand a water pressure of 0.6MPa for 1 hour without leakage
4. Installation and environmental adaptability
Installation conditions: ambient temperature 5-35 ℃, relative humidity ≤ 70%
Applicable scenarios: Suitable for both indoor and outdoor use, altitude<4000m, temperature range -50 ℃~50 ℃
5. Advantages compared to traditional connectors
Maintenance free, lifetime sealed, avoiding the risk of ceramic sleeve terminal explosion
Low partial discharge value, strong pollution resistance, suitable for high pollution environmentsTechnical Specifications
| Voltage Level (kV) | 138 | 110 | 66 |
|---|---|---|---|
| Maximum Operating Voltage (kV) | 145 | 126 | 72.5 |
| Weight (kg) | ≈85 | ≈85 | ≈85 |
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10-20 kV tunnel type quick connector (fiberglass waterproof shell)
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35kV composite/ceramic sleeve outdoor terminal
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10-20 kV tunnel plug-in quick connector (aluminum alloy waterproof shell)
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0.6/1kV Cast Resin Straight Through Joint
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