| 摘要 |
PURPOSE:To provide screwed type reinforcing steel rod having continuous, no- wall-lacking sprial nod, 4-roll type rolling mill is used in finish rolling, whereby the circumference of the roll pass is provided with a specifically engraved multilevel grooves. CONSTITUTION:The shape of recess for leader pass may be round or curved triangle, or alternatively round shape in which leader pass has 4 recesses corresponding to oval location of finish pass. The shape only requires that the oval positions of finish round recesses are related to the leader recesses in side relief minus. Such relation is held in the 4-roll type rolling machine 1, thereby assuring the rolling process of screw-type reinforcing iron having no-wall-lacking nod 4. |
