PURPOSE: To enable exact operation by providing a magent to a position close to a lowest part of a hanger and inhibiting oscillation of the hanger accompanying the transportation of the hanger caused by the magnetic force of the magnet.

CONSTITUTION: In a booth for powder coating, removing and recovering of powder paint sticking to a part machined precisely of an object to be coated, a magnet plate 18 is laid along the passage of a hanger 12 and a mild steel sheet 17 as a magnetic material is fixed to the bottom end face of the hanger 12. When the hanger 12 attached with an object to be coated 1 is suspended by a conveyor 11 and transported above the magnet plate 18, the mild steel sheet 17 fixed to the bottom end face of the hanger 12 is influenced by the magnetic force of the magnet plate 18. The oscillation of the hanger is inhibited, so the coating operation utilizing a robot is executed excatly.