Abstract: The drilling equipment for the canopy seal weld was developed to drain the residual radioactive coolant from the steam generator during the disassembly of the canned reactor coolant pump in China Advanced Passive Power Plan t (CAP1400) and Advanced Passive Power Plant (AP1000). The results show that the expected sealing effect of the device is satisfied and there is no leakage of coolant during the whole process; the drill tool and machining parameters are optimized and  the debris is small and fragmented, which can be drained with the coolant; the whole system is with compact structure and easy-control process, and can be remotely operated.