Taper-faced compression ring and wire therefor

A taper-faced compression ring comprising:

• an upper surface;
• a lower surface;
• and
• an outer peripheral surface of said ring, wherein the outer peripheral surface of said ring is formed of an outward inclined first tapered portion and second tapered portion,
• the outward inclined first tapered portion is adjacent to the upper surface, the outward inclined second tapered portion is adjacent to the lower surface, and the outward inclined first tapered portion and the outward inclined second tapered portion are adjacent to each other, and
• an inclination angle θ2 of said second tapered portion is larger than an inclination angle θ1 of said first tapered portion, so that the outward inclined second tapered portion extends outwardly from a lower end of the outward inclined first tapered portion,
• said second tapered portion of the outer peripheral surface has the inclination angle 82 of 3-10°,
• said second tapered portion has a lapped surface, which is located radially outward than an outer end of said first tapered portion by 0.002-0.015 mm, and
• said lapped surface has a contact width of 0.060-0.125 mm, and wherein said taper-faced compression ring attached to a piston slides up and down in a cylinder liner and the outer peripheral surface contacts with the cylinder liner.