| 摘要 |
An oil seal of the type having a metallic reinforcement rig whose outer peripheral portion is oil-tightly fitted into a housing, characterized in that after the formation of fabrication of said metallic reinforcement ring, the latter is subjected to a nitriding hardening process so that its durability of a raw material of said metallic reinforcement ring; and a seal lip of formed over the inner peripheral edge portion of an annular flange portion of said metallic reinforcement ring. |
