Abstract: An I-beam blank is rolled from a bloom by rolling into opposite edges of the bloom respective central triangular section notches of predetermined apex angle, apex radius of curvature, width, and height in a succession of roll passes. According to this invention the radius and apex angle of the notches are progressively increased a plurality of times during the succession of roll passes. Then the notches are pressed by rolling generally out of the bloom edges in at least one final rolling pass, thereby flattening these edges. The rolling passes are carried out between respective pairs of rolls having facing grooves bases and the roll pairs of the grooving steps are formed with respective triangular-section ridges complementary to the notches being formed. In addition the bloom is rolled repeatedly in the first pair of grooves until the material of the bloom flanking the notch mainly fills these grooves, that i until the bloom bottoms in the grooves.