Sealing ring combination

The combination of a cover ring and a sealing ring for positioning in axially abutting relation in a recess of a casing and around a reciprocating piston rod which extends through said recess, wherein

• said cover ring is formed of a plurality of radially-abutting cover ring segments and which in cross section defines a front portion defining an outer circumferential surface having a first outer diameter and a rear portion having an outer circumferential shoulder having a second outer diameter, said second outer diameter being less than said first outer diameter such that said cover ring has a generally L-shaped cross section, said cover ring defining a front face having a plurality of circumferentially-spaced radial channels therein and an inner circumferential surface having a circumferential groove therein which communicates with said front face,
• said sealing ring is formed of a plurality of tangentially abutting sealing ring segments and which in cross section defines a front portion having an inner circumferential surface which is positioned on said outer circumferential shoulder of said rear portion of said cover ring, and a rear portion, said front portion and said rear portion of said sealing ring providing said sealing ring with an inverted and reversed generally L-shaped cross section, and
• a common peripheral spring around said cover ring and said sealing ring to press said cover ring and said sealing ring against said reciprocating piston rod.