Wire for I-shape oil rings and producing method of the same

摘要

Provided is a wire rod for an I-type oil ring, which includes right and left rail portions and a web portion connecting the rail portions, which has an oil hole or a molten through hole formed in the web portion, and which has a circumscribing circle diameter of 10 mm or less in its transverse contour. The molten through hole has such a remolten portion formed on its exit side as encloses the exit of the molten through hole. The remolten portion exceeds such a molten portion in the transverse section along the center of the molten through hole as is formed in the molten through hole, and is formed to have 200 μm or less from the outer circumference of the molten through hole and 100 μm or less in the depth direction of the molten through hole.

主权项

1. A method of producing a wire for I-shape oil rings, which wire comprises a left and a right rail sections, and a web section connecting the rail sections with each other, has oil holes as through holes formed by melting, and has a diameter of not more than 10 mm which is defined by a circle circumscribing a contour of a cross section of the wire,
wherein the method comprises the steps of: piercing the through holes by means of laser; and forming a remelted and solidified portion surrounding an outlet of each of the through holes by means of laser, wherein the remelted and solidified portion is formed so as to exceed a melted and solidified region around the through hole but not to exceed 200 μm from the periphery of the through hole, when viewing a cross section of the wire taken along the axis of the through hole, and wherein the remelted and solidified portion is formed so as not to exceed 100 μm in a depth direction from the outlet of the through hole.