66~110kV Prefabricated Insulation Straight Intermediate Joint
✅High Reliability and safety
✅Convenient Installation, High Efficiency
✅Excellent Performance
- Product Introduction
66~110kV prefabricated insulation straight intermediate joint is a pre-fabricated, straight-through type cable joint used to connect two high-voltage cables of the same voltage level (66kV to 110kV). Its core feature is that its main insulation layer is pre-formed in the factory, requiring only on-site assembly, thereby ensuring extremely high reliability and consistency.
Model Meaning
Structure and Working Principle
Pre-fabricated Insulating Component:Pre-formed using high-performance insulating materials like silicone rubber. It contains conductive shielding layers and stress control layers internally, effectively equalizing the electric field distribution.
Conductor tube: There is a high-conductivity metal connector used to crimp and connect the conductors of the two cables, ensuring good electrical connection and mechanical strength.
Outer Shell and Sealing System: Typically includes a metal or high-strength fiber-reinforced composite protective shell that provides mechanical protection. Combined with internal and external waterproof seals, it forms a complete sealing system to prevent moisture and water ingress.
Installation Method: Pre-fabricated joints are usually installed by "on-site expansion and fitting" or "sliding insertion".Upon retraction, it forms a constant, tight interfacial pressure with the cable insulation surface.
Technical parameter
|
Item |
Technical parameters |
|
Rated voltage and frequency |
64/110kV,50Hz |
|
Max operation voltage |
126 kV |
|
Ambient temperature |
-40°C ~+40°C |
| Maximum conductor temperature during normal operation |
90°C |
| Maximum conductor temperature during short circuit | 250°C |
|
Applicable cross section |
240~1600mm2 |
|
Partial dischange test(at ambient temperature,96kV) |
No detectable discharge at the declared sensitivity (5 pC or better) |
|
Thermal cycle voltage test(128kV,95°C ~100°C ,heating 8h,cooling 16h) |
finished 20 cycles |
|
Partial dischange test(at high temperature,96kV) |
No delectable discharge at the declared sensilivity (5pC or better) |
|
Impulse voltage test followed by power frequency voltage test - Impluse voltage test(95°C-100℃,±550kV,10 times each) - powor frequency voltage test(160kV,15min) |
No breakdown or flashover |
|
Outer protection test for buried joints |
|
|
DC voltages tests Between metal sheaths(DC 25kV/1min) Between metal sheaths and ground (DC 25kV/1min) |
No breakdown |
|
Impulse voltage tests Between metal sheaths(+75kV, 10times each) Between metal sheaths and ground (+37.5kV,10 times each) |
No breakdown
|
Main Features and Advantages
High Reliability:
The main insulation is produced in a factory dust-free environment, avoiding impurities, air gaps, and human errors possible in manual on-site wrapping. This ensures highly consistent and stable insulation performance.
Convenient Installation, High Efficiency:
reducing installation time (often by more than 50%).
Reduces dependence on installer skill, simplifies the process, and minimizes the risk of human error.
Excellent Performance:
Electrical Performance: Superior dielectric strength and resistance to partial discharge.
Mechanical Performance: Good elastic memory and tear resistance, capable of accommodating slight cable bending and vibration.
Weather Resistance: Silicone rubber materials offer outstanding resistance to UV, ozone, and a wide temperature range (-50°C to +90°C).
Compact Design: The structure is compact and relatively small, saving installation space.
Application Scenarios
● Urban Power Grids: Straight-through connections for underground cable transmission lines.
● Power Plants and Substations: Connections between outlet bays and cable sections.
● Large Industrial and Mining Enterprises: Connections for main power supply lines.
● Tunnels and Bridges: Long-distance cable lines traversing special terrains.
Hot Tags: 66~110kv prefabricated insulation straight intermediate joint, China 66~110kv prefabricated insulation straight intermediate joint manufacturers, suppliers, factory, lightning electrical arrestor, Medium Voltage APG Epoxy Sleeve, Rear arrester, quick splice wire connectors, lightning and surge arrester, plug termination
