STEEL-MADE COMBINED OIL CONTROL RING

摘要

PROBLEM TO BE SOLVED: To facilitate the manufacture and management of a metal mold and a product inspection in a steel-made combined oil control ring of a type for forming a recessed part on the lug part of a spacer expander to prevent the single rotation of a side rail by improving the shape of the recessed part. SOLUTION: The recessed part 4 is formed in an isosceles triangular shape so that an apex part 5 is located in the circumferential center part of the circumferential surface of the lug 3, and both side end parts 6 are located in both circumferential end parts of the lug part 3. The apex part 5 is formed in a curved surface having a circumferential width of 5-30% of the circumferential width of the lug part and a curvature radius of 0.1-0.6 mm, and the radial depth of the apex part to both the side end parts 6 is set to 0.02-0.1 mm.