Sand mixer applied to intelligent casting island

The invention discloses a sand mixer applied to an intelligent casting island in the technical field of sand mixers. The sand mixer comprises a base, a conveying pipe is fixedly connected to the upper portion of the base, the other end of the conveying pipe is rotationally connected with a propelling pipe, a mixing pipe is arranged in front of the propelling pipe, and a discharging opening is formed in the bottom of the front side of the mixing pipe; an auger is arranged in the propelling pipe, a rotating mechanism is arranged on the rear side of the auger, and the rotating mechanism is used for driving the auger to rotate so as to push the sand grains and the binder which are conveyed into the propelling pipe by the conveying pipe into the mixing pipe; a mixing mechanism is arranged in the mixing pipe and is used for fully mixing sand grains and a binder in the mixing pipe; a replacement mechanism is arranged at the bottom of the propelling pipe and used for replacing the auger in the propelling pipe under t