| 摘要 |
PROBLEM TO BE SOLVED: To obtain an efficient economical method for manufacturing a channel with a projection, a cross section in the width direction of which is approximately an F-shape and which is used for rails for a magnetically levitated linear motor car transportation systems by normal conduction. SOLUTION: Using vertically asymmetrically grooved rolls, 1) a base stock is made into a rough formed material 11 having an approximately H-shape in the cross section in the width direction. 2) Using vertically and horizontally asymmetrically grooved rolls, the rough formed material is made into approximately an h-shape by disappearing by reducing one side of a 1st flange 101 and feeding steel in that part into the other part. 3) To preventing the generation of bend (camber) at the time of cooling after the completion of rolling, in the middle of that process, partial cooling is executed in the vicinity of the 2nd joined part 205 of the triple point of the approximate h-shape for making temp. difference in the interior of a slab not more than a certain value, 4) using the vertically and horizontally asymmetrically grooved rolls, bending work is added to the 3rd deformed flange of the projected part upward the approximately h-shape in the extended direction of the width direction of the web 200 and the cross section of approximately F-shape is formed. |
