Method for intermediate connection of tubular busbars

Intermediate connections for insulated tubular busbars are typically achieved using specialized connecting devices that ensure mechanical stability, electrical continuity, and equipotential treatment.

Overview of Intermediate Connection

Tubular busbars, often made of copper or aluminum and externally insulated, require reliable intermediate connections to extend their length or connect segments within substations or power assemblies. The connection must maintain high current-carrying capacity, mechanical strength, and electrical safety, while preventing galvanic corrosion and ensuring proper insulation. Common Methods1.

Bolted Joints Bolted connections involve overlapping busbar ends and securing them with bolts and washers. This method is field-friendly and provides reliable mechanical and electrical contact. Proper torque and washer sizing are critical to ensure uniform pressure and minimize contact resistance.

2.

Press-

Fit or Solderless Connections High-force press-fit interfaces allow busbars to be connected without soldering. These connections provide excellent conductivity, handle thermal expansion, and reduce assembly complexity. They are particularly suitable for high-current, compact power applications where heat-sensitive components are present.

3. Forming with Auxiliary Elements This method uses mechanical interlocking, such as semi-tubular rivets inserted through aligned holes in the busbar ends. It generates high contact pressure along the overlapping area, improving electrical performance and mechanical stability.

Progressive forming tools can perform lancing, bending, and forging operations to secure the joint. 4. Specialized Intermediate Connection Devices For insulated tubular busbars, patented intermediate devices include a connecting body with a lining core and components for equipotential treatment.

These devices allow the ends of insulated busbars to be joined while maintaining insulation integrity and electrical safety. They can incorporate manual wrapping, insulating shields, or cold-shrinkable joints to enhance performance and reliability.

Key Considerations

Material Compatibility: Ensure copper-to-aluminum connections are treated to prevent electrochemical corrosion. Current Rating: The number of clamps or connection points should match the busbar's continuous current rating. Mechanical Strength: Connections must withstand short-circuit forces, wind loading, and thermal expansion.

Insulation and Safety: Intermediate devices should maintain insulation and provide equipotential bonding to prevent electrical hazards.

Conclusion

The choice of intermediate connection method depends on current rating, environmental conditions, and installation constraints. For insulated tubular busbars, using a dedicated intermediate connection device with proper equipotential treatment is the most reliable approach, while bolted or press-fit connections may be suitable for less demanding applications or field assembly. Proper design ensures long-term electrical performance, mechanical integrity, and safety.