| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method for protecting a slidable cylindrical end portion capable of ensuring the sufficient cushioning property by a single packing material and easily slidable in the axial direction, and its structure. SOLUTION: A square packing sheet 3 is positioned at an end portion of a rib pipe 1, the packing sheet 3 is folded toward an outer circumferential surface side at a circumferential edge of the end portion of the rib pipe 1 so as to be abutted on the outer circumferential surface of the rib pipe 1, a folding line 4a is formed along a diagonal from a part corresponding to the circumferential edge of the end portion of the rib pipe 1 to four corners, pleat parts 4 of four pieces are formed with the folding line 4a as a ridge, the folding line 4a is formed parallel to the axis of the rib pipe 1 at the root of each pleat part 4, and each pleat part is folded and multiply wound around the outer circumference of a cylindrical body at the folding line, and the pleat parts are bound to the cylindrical body by a binding means.</p> |
