| 摘要 |
PURPOSE:To prevent the plate surface of a plate-shaped section from generating sink marks by making the suction density of a section corresponding to the plate surface of a plate-shaped section, crossed by crossing sections of an extrusion molded product, higher than the suction density of other sections, out of the suction cooling faces of sizing dies. CONSTITUTION:The plate surface of a plate-shaped section 16, crossed by crossing sections 17 of an extrusion molded product 10, is sucked to suction cooling faces 22 of sizing dies 21A and 21B with suction density higher than that of other sections, and said plate surface is adhered securely to the suction cooling face 22 and cooled more strongly to the suction cooling face 22 than other sections. Accordingly, the sections where the plate-shaped section 16 and crossing sections 17 are crossed each other, and the timing of cooling and solidifying is faster than the other sections, despite thickness cooled by the suction cooling faces 22 of the sizing dies 21A and 21B being larger than the other sections. By said process, shrink strain of the extrusion molded product 10 is not concentrated on the crossing section of the plate-shaped section 16 and the crossing section 17. |
