FIELD: mechanical engineering; internal combustion engines. SUBSTANCE: according to proposed invention, in internal combustion piston engine, particularly large displacement diesel engine with at least one piston fitted in cylinder and provided with ring grooves in which piston ring is installed to partially contact with effort to cylinder and with ends limiting the gap, at least top piston ring is provided with several grooves located in zone of its outer surface. In initial condition, summary cross-section of grooves does not exceed cross-section of gap limited by ends of worm out piston ring. EFFECT: increased service life. 14 cl, 2 dwg _
