PISTON RING

The present invention relates to a piston ring destined to be used for internal combustion engines, consisting of two segments and of a spacer, wherein, given its constructive configuration, the possibility exists to increase the initial unit pressure of the ring at the skirt of the cylinder, allowing a low-level oil consumption during the run-in phase. The steel piston ring consisting of a spacer or expansion element and two segments, wherein the segments have a radial dimension (3) between 1.50 mm and 1.90 mm, and a height (2) between 0.30 mm and 0.40 mm,a concave profile with recesses (4) between 0.015 mm and 0.030 mm, with a clearance (5) of 0.150 mm, wherein the segments are wound by means of a matrix box device (10) and of a roller, wherein the ring has a circularity, expressed in the form of a decomposition as a Fourier series, with amplitudes (N) smaller than 0.10 µm for orders higher than 10.