Operating equipment such as turbine units, large hydraulic units, and large compressors are critical to operations and have major costs associated with maintenance activities or downtime. Advanced annual testing provides an additional layer of insurance, recommended by organizations like EPRI and ASTM. The added testing is aligned with common issues that these large reservoir units often encounter and is designed to provide remaining useful lifetime frames to allow planned maintenance, instead of reactive downtime.
Large Hydraulic Units
Additional Testing Included:
Lubricant color change can be used to signify a change in lubricant chemistry. Oil oxidation, mixing of lubricants, and thermal degradation typically cause a lubricant to darken overtime. An unused, reference lubricant can be measured against a glass slide ranging from 0.5 to 8.0, measuring 0.5 increments. The in-use lubricant can then be measured in a similar fashion and used to trend lubricant color and opacity when compared to the reference.
Demulsibility testing measures a lubricants ability to release water. A lubricant’s ability to shed water is important in preventing the production of emulsion state. When a lubricant loses the ability to separate from water, clouding or even foaming can occur and draw the water into contact with components under load, expediting wear and chemical reactions.
Foam Testing measures a lubricants tendency to foam. Foaming causes cavitation of air or vapor bubbles caused by a lessened pressure in the lubricant and leading to implosion of the lubricant in higher-pressure areas of the lubricant. Cavitation can lead to the creation of holes or pits in metal applications, leading to additional wear and improper component protection. Foam sequence testing is most popular in hydraulic and turbine applications. Running Foam Sequence I, II, and III allows for air to be introduced to the lubricant under different temperatures to gain a more accurate and precise understanding of the lubricants foam tendencies.
The Rotating Pressure Vessel Oxidation Test (RPVOT) is a test used to determine the oxidation stability of an oil. RPVOT is used almost exclusively for large reservoir units, turbines and hydraulics being the most popular component type. Results are reported in minutes and are used as a trending value. Oxidation is a mode of lubricant degradation. As oil oxidizes, it forms acids and insoluble oxidation products, which can lead to the formation of sludge and/or varnish.
The Remaining Useful Life Evaluation Routine Test, or RULER for short, measures the amount of sacrificial antioxidants which remain in the oil in order to protect it. Oxygen in the air is reactive, especially under high temperature and pressure conditions. To prevent the oxygen from reacting with the lubricant, certain antioxidant chemicals called amines and phenols are sacrificed. When all the sacrificial chemicals are used up, the oil is highly susceptible to oxidation, or chemical destruction.
Rust A is a test utilized to detect a lubricants ability to protect against water contamination and its ability to create rusting on mechanical components. The test is primarily run for turbine/hydraulic units.
Membrane patch colorimetry is a test used to measure the varnish potential of a lubricant. By running the lubricant through a membrane patch, insoluble contaminants are extracted from a used oil sample. The membrane patch isolates the agglomerate insoluble by-products that are generally considered varnish. The intensity and color of the resulting membrane patch generates a value, the higher the value, the higher the potential for varnish.
Available Test Packages
Our test packages provide the most complete information about the health of your turbine unit, large compressor, or large hydraulic reservoirs. These test help our Lubrication Program Managers to properly guide you with any necessary action items regarding the oil’s remaining useful life, the presence of varnish, and overall equipment condition.