PURPOSE: To form a stable up-loop without coil buckling of a coil, by tightly coiling a coil, coiled around a loose coiling device having vertical axis, around a horizontal axis by spirally twisting the coil along a specified imaginary cylinder.

CONSTITUTION: An annealed rolled coil 4, coiled around a loose coiling device having a vertical axis, is tightly coiled around a horizontal axis while being spirally twisted by approximately a half or one revolution along a slanted imaginary cylinder 12 of which bottom end is corresponded to the side of a loose coiling table. In this case, a diam. of the cylinder 12 is put as D, a point at one end of the coil which begins to contact the cylinder 12 is put as P1, and a point at the other end of the coil which ends a separation from the cylinder 12 afte the coil is twisted by 180° from the point P1 is put as P2. The min. value of the diam. D of the cylinder 12 is made to be sheet thickness of the coil (t)× 500, the max. value of D is made to be min. value of D×3, and the min. horizontally projected length A made between the midpoint, locating on the line which passes through the point P2 in the direction of coil width, and the point P1 is made to be sheet width W×1, and max. A is made to be W×3. Several following conditions are also to be satisfied, i.e. the min. value of the height H between the points P1 and P2 is W×1, and the max. value of H is W×3.5.