Centering rotary power drilling tool for removing welding spots and welding spot removing method

The invention relates to a centering rotary power drilling tool for removing welding spots and a welding spot removing method, and belongs to the technical field of handheld trepanning drilling tools. Comprising a drilling tool body which comprises a shell and a driving motor which is located in the shell and rotates; the drill bit clamp is of a hollow pipe body structure, one end of the drill bit clamp is rotationally connected into the shell, and the drill bit clamp rotates along with the driving motor; the trepanning drill bit is of a hollow pipe body structure, and one end of the trepanning drill bit and the other end of the drill bit clamp are coaxially connected and synchronously rotate; the centering needle rod extends into the drill bit clamp and the trepanning drill bit, and a tip is arranged at the front end of the centering needle rod and linearly moves in the drill bit clamp and the trepanning drill bit; the hammering mechanism is located in the shell and connected with the rear end of the centeri