The double discs in the blast wheel are riveted together to form the impeller body. The impeller body is equipped with eight blades, and the impeller body is mounted on the spindle driven by the motor together with the sub-pellets located at the center of the blast wheel. The cover is lined with a guard plate, and the orientation cover and the pill injection tube are mounted on the cover. At work, the abrasive flows from the intake tube into the blast wheel. The split wheel that rotates synchronously with the blade gives the abrasive an initial speed. The abrasive flies out of the window of the orienting sleeve and is thrown onto a high-speed rotating blade outside the orienting sleeve. After being further accelerated by the blade, it is projected onto the surface of the cleaned workpiece. Because the split wheel and the blade rotate synchronously, vibration-free transmission of the abrasive to the blade is ensured, thereby reducing wear on the blade.