摘要 |
An extrusion die having on the front surface thereof a bearing opening of the shape of a given section; a bearing surface corresponding to the section of the bearing opening formed over a length from the front surface to the rear surface of the die; and a draft formed from the bearing surface toward the rear surface; the bearing surface at each position on the inner circumferential line of the bearing opening being formed in such a fashion as to have a bearing length which is substantially determined in accordance with the shape of the bearing opening at that position wherein, when viewed with respect to a sectional face orthogonal to the inner circumferential line, a straight line corresponding to the bearing surface and a straight line corresponding to the draft intersect at a depth position substantially equal to or larger than the bearing length at that position, and the depth position where the intersection point exists is in a depth position which is substantially determined in accordance with the shape of the bearing opening at the respective positions on the inner circumferential line of the bearing opening, and a method of making the same.
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