PURPOSE: To form a conveyer into small size and to narrow its setting area, by providing two discharge ports in a fork structural hopper main unit and shot blast machines respectively in the bottom of the two discharge ports and setting up this conveyer, which is for conveying a process-finished product, between bottom positions of these shot blast machines.

CONSTITUTION: A product to be processed is continuously supplied coming from a belt conveyer 1, and a product distributing plate 4 of a hopper 2 sorts the product alternately into a left chamber 13a and a right chamber 13b of a hopper main unit 3 charging these chambers with the product. Next contracting a cylinder 6a to open a discharge port of the left chamber 13a, the product charged into the chamber 13a, is contained in the rotating drum 9a of the corresponding shot blast machine 7a and on performing shot blasting is discharged onto a conveyer 10. Similarly the right chamber 13b is charged with the product, and a shot blast machine 7b mounted is also changed with the product is a rotary drum 9b staggering the time, thus performing shot blasting and discharging the process-finished product onto the common conveyer 10.