12kV series vacuum arc extinguishing chamber adopts ceramic insulated shell. The parts of the outdoor 1250A 12kV vacuum interrupter are brazed into several parts, and then assembled into a whole empty interrupter, and then the processes of exhaust, baking, degassing and brazing sealing are completed in the vacuum furnace. This process is relatively simple and generally has 7 processes, so it has high efficiency and less man-made pollution. In addition, the vacuum interrupter produced by this process has a high baking temperature (800 ℃ ~ 900 ℃), so the exhaust is complete. We can customize the vacuum interrupter of 1.14kv-72.5kv circuit breaker