| 摘要 |
PURPOSE:To manufacture a titlted ring which causes no deformation in a ring stick and B size at the time of coiling, by executing groove-working for accumulating sludge to a piston ring base material, and after that, and executing the coiling such that the groove surface forms an inside circumferential surface. CONSTITUTION:To a steel piston ring base material, grooving for accmulating sludge is performed to an inside circumferential surface 1 by die drawing or a forming roll. Subsequently, adherence wind coiling is executed so that this groove is provided on the inside cicumferential surface of a piston ring, and subsequently, one place on the circumference which has been coiled circularly is detached so as to be like a ring. Subsequently, this detached port is expand- opened to prescribed size and is treated by heat, by which a piston ring having prescribed tension is obtained. In this case, when coiling is executed after a sludge accumulating ring-like groove 2 has been formed on the inside circumferential surface, no variation is generated in B size (B2) which is functional important size of the piston ring. Accordingly, the ring is manufactured more easily. |
