The manufacturing process for indoor high-voltage vacuum circuit breakers centers on core component fabrication, assembly of the complete unit, and rigorous quality inspection; the precision of these key processes directly determines the equipment's operational reliability.
Core Component Manufacturing Processes
Vacuum Interrupter Encapsulation: Utilizes integrated vacuum brazing with silver-copper filler metal; the holding temperature in the vacuum furnace is maintained at 1080°C ± 5°C for 15 minutes. This ensures porosity-free weld seams and a stable internal vacuum level exceeding 1.3 × 10⁻⁴ Pa, meeting national standards.
Helium Mass Spectrometry Leak Detection: Airtightness testing is performed on the encapsulated interrupter, requiring a leak rate of ≤ 1 × 10⁻¹³ Pa·m³/s to ensure the long-term maintenance of a high-vacuum environment and prevent the risk of arc restrike.
Insulated Pole Molding: Employs hydrophobic epoxy resin or SMC (Sheet Molding Compound) insulation materials. Molding is achieved via a casting process with an optimized shed structure, significantly increasing creepage distance and making the unit suitable for industrial environments with high humidity or mild pollution.
Enclosure Fabrication: Uses sheet metal stamping combined with electrostatic powder coating. Enclosure dimensions are precisely matched to the voltage rating, and the IP protection level complies with the GB 1984-2014 standard, ensuring effective dust resistance and insulation for indoor applications.
Complete Unit Assembly Processes
Modular Mechanism Assembly: Laser positioning tooling is used to assemble spring or permanent-magnet operating mechanisms, ensuring core coaxiality within 0.02 mm and contact bounce times (during opening/closing) of ≤ 2 ms, thereby significantly reducing mechanical wear.
Step-by-Step Assembly Line: Standardized assembly of the main shaft assembly, shock absorbers, conductive circuits, and secondary circuits is carried out sequentially on an automated circulating conveyor line. Each step involves drawing verification and the completion of process tracking cards to ensure precision in transmission component fit. Secondary Circuit Integration Process: Strictly adheres to standardized secondary wiring procedures and incorporates interfaces for online monitoring of mechanical characteristics; enables real-time recording of data such as opening/closing speeds and contact wear, ensuring zero-error signal transmission.