PURPOSE: To remove desired amts. of refractories from the side walls of a tapping spout efficiently with consumption of inexpensive materials by blasting shot blasts through a nozzle facing the side walls of the tapping spout and moving the nozzle in the longitudinal, depth and width directions of the spout.

CONSTITUTION: A carriage 1 is moved in the upper part of a tapping spout 24 up to the position of the part to be repaired on a rail along the spout. The height of a nozzle 4 is adjusted with a cylinder 16 and the horizontal position is adjusted with a cylinder 18. The wheels 22 of a hood 21 are brought into contact with the surface on the side wall 27 of the spout 24. A compressor 5 on the carriage 1 is then started and compressed air is fed to the nozzle 4 through a flexible pipe 9 and an L-shaped transport pipe 3; on the other hand, a valve 8 is opened to start injection of the shot materials 25 in a hopper 6, so that shot blasts are sprayed onto the wall 26. The nozzle position is adjusted by the cylinder 16 and the traveling of the carriage 1 in succession to the above, whereby the worn refractories are removed from the desired area to be repaired. The depth of the removal is adjustable as desired with the cylinder 18.