Prerolled concrete reinforcing bar - producing depressions to reduce the work of forming ribs in finish rolling

摘要

A pre-rolled bar for concrete reinforcing bar provided with several ribs running sinuously in the axial direction, has depressions formed between the ribs produced in final rolling. The depressions may be circular or elliptical and may be formed diametrically opposite each other with succeeding depressions at 90 degrees to each other. Pre-rolling reduces the displacement of material required in final rolling and thus deeper ribs can be formed.