What is ISO 6626-3 - Coil-spring-loaded oil-control piston rings about?
ISO 6626 is a series of international standards on piston rings that discusses coil-spring-loaded oil control rings.
ISO 6626-3 is the third part of the ISO 6626 series of documents that specifies the essential dimensions of coil-spring-loaded oil control rings made of steel, of piston ring types SOR (with R-shaped groove) and SOV (with V-shaped groove).
ISO 6626-3 applies to coil-spring-loaded oil control rings made of steel with a diameter from 60 mm up to and including 160 mm for reciprocating internal combustion engines. It can also be used for piston rings in compressors working under analogous conditions.