METHOD OF MANUFACTURING SIDE RAIL FOR COMBINED OIL RING

摘要

PROBLEM TO BE SOLVED: To provide a method of manufacturing a side rail for a combined oil ring, allowing a small change in groove size and ensuring prevention of circumferential relative sliding between the side rail and a spacer expander. SOLUTION: A laser light is radiated to the inner periphery of a ring molded wire material to form a plurality of grooves in the inner periphery of the side rail.