Abstract Moisture contamination in in-service lube oils is perhaps one of the most destructive forms of engine corrosion second only to particle contamination. Water contamination in oil can be categorized into three forms of water; Free, emulsified, and dissolved. All forms of water have direct consequences to the oil and gears of the engine, but indirect consequences as well. Direct consequences include changes in pH and viscosity which can be problematic in themselves. Other factors that affect engine corrosion are contamination of glycol, soot, and particle corrosion. The presence of water exacerbates each of these factors and can cause irreparable damage to the engine. It is therefore imperative for routine moisture testing of in-service lube oils. Traditional methods for water analysis are fourier transform infrared (FTIR) spectroscopy and Karl Fischer titration. The problem with these two methods are their sensitivity and the hassle of sampling (respectively). OELCHECK performs the crackle test on all oil samples. The water content is estimated with a visual inspection by a trained observer. Three common methods are the FTIR spectrum match, the visual crackle test and the Karl Fischer Coulometric Titration test (ASTM D 6304). The Karl Fischer test produces the most accurate information and is commonly conducted after a positive finding by either the FTIR spectrum match or visual crackle test. In place of a Karl Fischer titrator (KFT), a relative humidity sensor moisture analyzer is capable of the same precision as the KFT (10 ppm) but without the use of hazardous chemicals or breakable glassware. Using the relative humidity sensor instrument does not require a strong background in science to operate and is easy to optimize for each sample. Moisture Contamination: The Three-Headed Beast No matter the type of engine, gearbox, turbine or bearing, in-service lubricant oils are designed to accommodate heavy compressibility while remaining chemically inert and unreactive. Male high school. It is important that the viscosity of the oil remains unchanged and that the oil remains free of contaminants to prevent costly wear on the engine. Moisture contamination in in-service lube oils is perhaps one of the most destructive and expensive forms of engine corrosion, second only to particle contamination. Water contamination in oil can be categorized into three forms of water; Dissolved, Emulsified and Free Moisture each of which causes its own direct and indirect problems to the engine. [1] Dissolved Moisture Dissolved moisture is the lowest level of moisture contamination in lubricant oils. This moisture is derived from ambient air humidity slowly interacting with the lubricant oil overtime. Usually, the more additives the oil contains, the more hygroscopic (water attracting) the oil will become. Fundamental of microprocessor by b ram pdf download. Acceptable levels of dissolved moisture typically range from 50-300 ppm (or 0.0050% – 0.0300%). [2] This level of moisture does not greatly affect the compressibility or viscosity of the oil but is the most chemically reactive water species since it is dispersed throughout the oil. The bottom line: Dissolved water can degrade metal and deplete additives Direct Effects • Dissolved water molecules will coat any polar metal surface it finds within the engine. Under routine engine pressure and heat, this small amount of water can be stripped of its oxygen constituent and release hydrogen ions, which will chemically degrade the face of the metal (ball bearings and gears). This weakens the metal and microscopic flakes will begin to shed from the metal leading to particulates in the oil leading to gear corrosion. * About this release - Language: English (en-US) - Channel: Volume License - Version: 16.0.4639.1000 - Proofing Tools: English, French, Spanish - Updated: August 14, 2018 - 64-bit version runs on 64-bit systems only - OS: Windows 10/8.1/8/7 SP1 + Windows 10 Server, Server 2012 R2/2012/2008 R2 -.NET version:.NET 3.5 required. Microsoft office 2007 professional torrent tpb proxy. Indirect Effects • Dissolved water molecules will actively seek other polar molecules which may include additives such as detergents, antioxidants (amines or phenols), friction modifiers, and anti-wear additives (such zinc phosphates). Because water molecules are sequestering these agents, these additives lose their functionality which may cause problems to the engine. Emulsified Moisture If left unchecked, the dissolved moisture will continue to increase within the oil sample until it reaches a saturation point. At this point, any added water will precipitate out as cloudy emulsified micro droplets. Like the mayonnaise you would put in your sandwich, this form of moisture is created by the continuous churning, heating and high pressurization of water into oil. ![]() The saturation point varies for different lubricants. Mineral oil has a saturation level of 100 ppm (0.0100%), while some hydraulic fluids have a saturation level as high as 5000 ppm (0.5000%). As some oils age, the saturation point may increase depending on the type of oil and the additives used in the lubricant.
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