PURPOSE: To mechanically and completely eliminate a scale on the surface of a steel bar by pressing plural rollers whose outside peripheral surface has been formed to a rough surface by a groove, etc., in the direction vertical to the advance direction of the steel bar on the way, at the time of carrying the heated steel bar to a forging machine.

CONSTITUTION: On the surface of a steel bar W of a high temperature, which is heated by an induction heater 3 and carried to a forging machine 5, a scale which has been generated in the course of heating adheres. Before this steel bar W goes into the forging machine 5, the surface contacts the outside peripheral surface of the steel bar W, and two pieces of scale scraping rollers 6' 6' whose surface has been roughened by forming a long groove 10, etc. are placed in the upper and lower parts, and by a spring 27, the surface of the steel bar is pressed by shifting the phase in the direction vertical to its advance direction, and also, in the peripheral direction of the steel bar. By this processing, a scale on the surface of the steel bar W is easily and completely eliminated without depending on a person's help.