Abstract: A lid assembly, for a packing container, includes a lid ring of a plasticizable, thermoplastic polymer material and a dimensionally stable lid part, to be placed on the lid ring. The lid part (or the lid ring) has a layer of a peelable plastic material, on a side facing the lid ring (or the lid part), that contains a sealable, thermoplastic polymer or is coated with a cover layer of such a polymer. The lid ring (or the lid part) has an end face facing the lid part (or the lid ring), with two parallel circumferential projections, arranged at a distance of at most 3 mm and sealed to the peelable layer or to the cover layer of the lid part (or of the lid ring). A packing container with such a lid assembly as well as a method for manufacturing same by ultrasonic welding are also provided.