Then they used the crane to stabilize the circuit breaker, removed the outrigger, laid the guide rail and track timber beneath the circuit breaker, installed the circuit breaker mobile trolley, and connected the circuit breaker to the mobile support.

After ensuring a reliable connection, the workers loosened the crane hook, unscrewed the bolts on the insulating basin on the upper side of the circuit breaker and the current transformer side, allowing the circuit breaker to slowly descend.

Next, they used the tooling handle to move the circuit breaker laterally, ensuring that its longitudinal movement is not interfered with by the support, so that the circuit breaker can be safely removed.

To ensure safe and controllable maintenance processes, State Grid Anhui Extra High Voltage Company organized inspection units to conduct on-site investigations in advance. They refined the initial inspection contents and maintenance implementation standards, strengthened risk control measures across various disciplines, established a multidimensional safety protection network on site, and resolutely controlled the maintenance process.

Furthermore, they refined the implementation of a comprehensive maintenance plan for large-scale circuit breaker operations, developing multiple schemes encompassing hoisting, on-site maintenance, and preventive testing.

During the construction phase, operation and maintenance personnel intensified on-site management and control, utilizing remote intelligent patrols as a means to conduct real-time dynamic supervision of key areas, operators, and critical maintenance steps. This approach aimed to create a comprehensive safety protection network on site.

After 13 consecutive days of diligent effort, the comprehensive maintenance of 5041 and 5052 circuit breakers at the UHV Wuhu station was successfully completed. The replacement of the 500kV circuit breakers involved about 50 inspection personnel from four inspection units, who carried out 54 maintenance tasks including circuit breaker removal, reinstallation, lightning arrester, voltage transformer primary lead removal, reinstallation, and withstand voltage tests.