ASTM D4310M extended oxidation test (2,600-hr duration) uses 99.5% oxygen flow, high temperature (95°C), and copper and steel catalysts to accelerate oxidation to determine the rate of acidity buildup in oil samples. Test results show sludge samples after fluids were filtered.
Petro-Canada’s Environ MV hydraulic fluids reduce harmful sludge buildup in systems, as demonstrated by the ASTM D4310M extended oxidation test (2,600-hr duration). In this standard test, 99.5% oxygen flow, high temperature (95°C), and copper and steel catalysts were used to accelerate oxidation to determine the rate of acidity buildup in Environ and oils from other suppliers. After this extended test, the fluids were filtered and sludge samples examined. Environ MV outperformed competitors with significantly lower sludge formation at similar test hours.
Another important test for hydraulic fluids is ASTM D943. In this standard industry test, again, 99.5% oxygen flow, high temperatures (95° C), and copper and steel catalysts were used to accelerate oxidation to determine the rate of acidity buildup in hydraulic fluids. Petro Canada’s Hydrex AW and oils from other suppliers were subjected to this test. Later, fluids were filtered and sludge samples examined. The Hydrex AW had significantly lower sludge formation than the other oils — even after the Hydrex AW was tested for a longer duration.
Another important consideration is seal compatibility. A common issue with hydraulic equipment is leaks from broken seals or insufficient seal swelling. Oil leaks often result from oil seals becoming brittle and cracking, a problem typically related to the compatibility of a product’s base oil. Hydrex hydraulic fluids have excellent seal compatibility because they use base oil that is free of impurities. Using pure base oils helps prevent oxidation, which also translates into longer oil life.
In closing, sludge can be incredibly damaging to hydraulic components, ultimately causing unplanned downtime and increased maintenance costs. In conjunction with proper filtration, the selection of a quality hydraulic fluid can significantly reduce oxidation and sludge buildup. By putting these practices in place, you can proactively minimize the effects of sludge in heavy duty hydraulic systems.
Robert Farthing, Category Portfolio Manager—Hydraulic Fluids & Greases
Petro Canada, Calgary, AB, Canada