Z-type and ZZ-type scraper rings in an external metal casing are used to remove impurities and excess lubricating medium from components and elements of machines operating in reciprocating motion.
Designed to work in a dusty environment (mines, construction machines, agriculture). Used in hydraulic drives and controls. The design of the Z and ZZ rings complies with the PN-88 / M-73051 standard.
What material are the scraper rings made of?
Z / ZZ scraper rings are a type of internal seals, usually made of NBR rubber. The Z-type scraper is entirely made of rubber, while the ZZ scraper has an outer metal casing, thanks to which the entire element becomes less flexible and more adherent.
Nitrile rubber (NBR) is resistant to media such as: oils (mineral, engine, transformer, plant and animal origin), mineral greases, gaseous fuels, gasoline, aliphatic hydrocarbons, non-flammable hydraulic fluids (HFA, HFB, HFC), and also dilute acids and bas
Advantages of using scraper rings
The Z scraper and the ZZ scraper extends and retracts into the piston rod. This removes water and scrapes dirt, sludge, and other debris from its surface, and then returns into the cylinder in a reciprocating motion.
Installing the hydraulic scrapers evenly distributes the oil over the cylinder surface. It also protects the machine from getting too much lubricant into the space above the cylinder. This ensures long-term performance of the machine, scraper ring and prevents damage to the remaining sealing rings.