Combating Harmful Sludge Buildup


Imagine you are running a marathon—24/7/365—with a coach right behind you, constantly demanding more speed and reduced time splits. While your training regimen may have prepared you for the challenge, once you start the race, how do you ensure that your joints and limbs keep operating? Performance fluids play an important role in hydrating a runner’s system, purging toxins from organs and lubricating joints. Hydraulic equipment has similar needs in maintaining system performance.

Heavy-duty hydraulic systems in today’s industrial plants and mobile equipment endure some of the toughest operating conditions there are, running under extreme pressures, at increasing speeds and working harder than ever. Now, in light of the trend toward smaller reservoirs, even more stress is being put on this equipment: Air and heat don’t escape as easily as they do with larger reservoirs. Water may not separate as effectively. Contaminants can accumulate faster. The rate of oxidation rises, as does the risk of harmful sludge buildup. Even with a good filtering system, excessive sludge can plug filters, increasing equipment wear and seriously damaging the hydraulic pump. An indicator of high varnish potential—a resinous matter that forms hard deposits on components—sludge can signal real trouble for your operations.

The bottom line…

As equipment runs harder, fluids can break down faster, risking total system failure and costly equipment downtime. A high-performance hydraulic fluid ensures optimal productivity while saving you money. But how do you go about selecting the right one?

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Starting with base oil free of impurities is a good first move. Base-oil purity can give you insight into the product’s resilience—i.e., resistance to oxidative breakdown. The purer the base stock, the more it retains its “fresh oil” properties and the longer it is likely to perform.

Oxidation tests are another tool that can be used to identify a high-performance hydraulic fluid—to demonstrate that a fluid significantly reduces sludge formation, especially at extended operating hours. This, in turn, translates into fewer changeouts, reduced downtime and increased operating efficiencies. In other words, the fluid works harder so machinery doesn’t have to. Petro-Canada’s HYDREX™ AW 46 is just such a product. Our studies indicate that not all hydraulic fluids are created equal.

In fact, Petro-Canada’s HYDREX AW 46 has been shown to produce significantly less sludge than several competitor products, even at longer test hours. In a standard industry test (ASTM D943M), a high temperature (203 F/95 C), 99.5% oxygen flow, 20% water and copper and steel catalysts were used to accelerate oxidation to determine the rate of acidity buildup in various hydraulic fluids. When sludge from these filtered test fluids was examined, the competitor samples indicated accelerated oxidation and degradation.

Return on Investment
Sludge can be incredibly damaging to hydraulic components. By minimizing oxidation and reducing sludge buildup, a high-performance hydraulic fluid saves you both time and money—and helps make your equipment’s never-ending marathon a lot easier to run. 

Petro Canada
Mississauga, ON, Canada

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