Rod seals for hydraulic cylinders seal the system pressure on the rod side of the cylinder aginst the athmosphere. They seal the pressures during the stroke phase and position holding operation of the cylinder. The individual profile design show specific behaviors and perfomance which need to be in line with the application´s requirements. There are single or tandem designs of reod sealing systems. The rod sealing system considers also the wiper and the guiding elements.
The rod seal is the most critical seal on any type of fluid power equipment preventing leakage of fluid from within the cylinder to the outside. Leakage through the rod seal can reduce 
e performance, and also in extreme cases can cause environmental issues.
Hallite offers a wide range of hydraulic rod seals for both single-acting and double-acting systems. These include a unique profiled NBR energised polyurethane (PU) seal, and a specifically designed three element seal for the mining industry comprising of an O-ring energiser, PU shell and a polyacetal anti-extrusion ring.
Particular attention should be paid to pair the rod seal and the wiper for the best sealing performance. If a less aggressive rod seal is paired with an aggressive wiper, the wiper can scrape off the microscopically thin film of oil that remains on the rod in microscopic surface imperfections during the return stroke, resulting in system leakage.
