A piston ring assembly has an expander spring of sheet material bent into an annular configuration. The expander spring has a circumferential series of radially oriented tongues and each tongue has an approximately axially bent leg. The tongues and legs are defined by stamped-out slots provided in the expander spring in an alternatingly radially inwardly and radially outwardly oriented circumferential series. The expander spring has stamping burrs bounding the slots. The piston ring assembly further has two laminar oil scraper rings arranged generally concentrically with respect to the expander spring. The laminar oil scraper rings are axially supported by the tongues and are radially supported by the legs. The burrs are situated such that they are submitted solely to compression forces derived from bending stresses generated as a result of bending the spring into the annular configuration.