Quote:
Originally Posted by BRPORSCHE
How is the oil analyzed? XRF?
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I guess the best way to understand it is that it can be broken down into 3 areas: Wear metal analysis, contamination analysis and oil condition analysis.
A sample sampl - 4-6 oz sample submitted to mail via fed ex, ups (USPS sucks so don't use them)
The lab enrolls your info and begins testing:
Wear Metals and Wear Debris:
Spectrochemical Analysis for Wear Metals:
The spectrochemical analysis measures different metals in parts per million (ppm) which represent equipment wear, as well as system contaminants and lubricant additives.
The listing below illustrates some major sources of wear metals but does not indicate all possible secondary sources. Abnormal wear is commonly indicated by a combination of metals.
Iron (Fe): Major component material in equipment manufacturing. Housing/Blocks, Cylinders, Pistons, Gears, Bushings, Bearing, Shafts, Valves, Rings, Rust
Chromium (Cr): Cylinders Liners and Guides, Bushings, Bearing, Shafts, Valve, Rods, Rings, Hydraulic Cylinders
Lead (Pb): Bearings/Bushings, Thrust Plates, Washers
Copper (Cu): Bearings/Bushings, Thrust Plates, Washers, Oil Cooler, Pumps, Disc/Disc Lining.
Tin (Sn): Bearings/Bushings, Pumps, Motors, Compressor Piston, Piston skirt overlay
Aluminium/Aluminum (Al): Pistons, Bearings/Bushings, Thrust Washers, Rings, Housing/Blocks, Oil Cooler, Cylinders and Cylinders Guides, Engine After-cooler
Nickel (Ni): Gears, Shafts, Rings, Valve Trains, Bearings/Bushings, Pumps
Silver (Ag): Bearings/Bushings, Oil Cooler, Some Gears and Shafts, Disc/Disc Lining
Titanium (Ti): Bearings/Bushings, Some Gears and Shafts, Turbine Blades, Valve Trains, Gear Trains, Some Shafts (additive in some HDMO’s)
Vanadium (V): Turbine Blades, Some Bearings and Bushings
The spectrochemical analysis measures different metals in parts per million (ppm) which represent contaminants, as well as equipment wear and lubricant additives.
Aluminium/Aluminum (Al): After-cooler Brazing Flux, Dirt if in combination with Silicon.
Boron (B): Engine Coolant
Magnesium (Mg): Seawater if present with sodium
Potassium (K): Engine Coolant, After-cooler Brazing Flux
Silicon (Si): Dirt (especially in combination with aluminium/aluminum and/or sodium), Gasket/Sealant Material, Engine Coolant
Sodium (Na): Engine Coolant, Seawater, by product from Natural gas (wet gas) transferring, Dirt in combination with silicon
Contamination Analysis
Water: Water as a contaminant will generally lead to increased corrosion, depletion of proper lubricating film, decreased lubricant performance life and increased acid formation.
Coolant: Coolant contamination will degrade lubricant service life and performance, create sludge and block lubricant passageways.
Fuel Dilution: Fuel dilution will decrease fluids viscosity, therefore affecting its lubricity properties. Fuel dilution also promotes degradation of lubricant service life and additive properties.
Soot: Excessive soot increases viscosity, creates excessive wear, and will tie up active additives needed for lubricant performance.
Particle Count (typically not done on engines or trannys unless your will to pay more and are really particular). “Clean Systems” require a minimum level of cleanliness in order to operate reliably. This is especially true for circulating systems with high pressure and close tolerance components. The ISO Cleanliness Rating is a convenient way to communicate the level of particulate contamination within a system based on the particle count for micron sizes greater than 4, 6, and 14.
Extra tests:
PQI: PQI is a valuable trending tool for monitoring the relative level of ferrous wear material within a lubricant sample.
Filter Patch: Filter patch inspection provides a visual assessment of wear particle and other solid debris present in a sample after collection on a 0.8 micron to 5.0 micron filter membrane and examined by a microscope.
Analytical Ferrography: Analytical Ferrography provides detailed information on different wear particles present in a sample. This is generally an exception test that provides information on the type of metal makeup of the wear particles present and how they were formed.
Oil Condition Analysis
Viscosity: Improper viscosity can affect a lubricants performance.
Too low of a viscosity will not create sufficient surface film to keep moving parts separated and prevent rubbing on opposing metal surfaces.
Too high of a viscosity will create excessive heat and reduced fluid flow within circulating systems.
A change in viscosity will indicate a change in the fluid performance integrity. A drop in viscosity generally indicates contamination with a lighter product, addition of an incorrect viscosity grade, and in some cases thermal cracking. An increase in viscosity can indicate oxidation and reduced service life due to age, addition of an incorrect viscosity grade, or excessive soot or insolubles content.
Base Number: Base number represents the level of alkalinity reserve available for neutralizing acids formed during the combustion process and may be introduced through recirculated exhaust gases. As the lubricant ages and the additive package depletes, the base number will decrease from its initial fresh oil value.
Acid Number: Acid number in a new lubricant represents a certain level of additive compounding. This can come from antirust, antiwear or other additives. The acid number can drop a bit after a lubricant has been in service for a certain period, which indicates some initial additive depletion. After a time the acid number will start to increase, which indicates the creation of acidic degradation products related to oxidation. The acid number is a means of monitoring fluid service life.
Oxidation Number: The oxidation number is a relative number that monitors increase in the overall oxidation of the lubricant by infrared spectroscopy. This test parameter generally compliments other tests for fluid service life, such as viscosity and acid number. Generally this test is not used as a primary indicator when all other tests are within normal limits. Accurate oil information is required to get the most valid test results.
Nitration Number: The nitration number is a form of oxidation that relates to chemical reaction with nitrogen, forming nitrogenous compounds also. Nitration is a relative number that monitors increase in the overall fluid degradation due to reaction with nitrogen and oxygen by infrared spectroscopy. This test parameter generally compliments other tests for fluid service life, such as viscosity and acid number. Generally this test is not used as a primary indicator when all other tests are within normal limits. Accurate oil information is required to get the most valid test results. Contributors to increased nitration can come from exhaust gas blow-by or reaction with natural gas products with the lubricant and heat. It is also an indicator of electrostatic discharge across filter surfaces in turbine oil.
Sulphation Number: The sulphation number is a form of oxidation that relates to chemical reaction with sulfur compounds also. Sulphation is a relative number that monitors increase in the overall fluid degradation due to reaction with sulfur compounds and oxygen by infrared spectroscopy. This test parameter generally compliments other tests for fluid service life, such as viscosity and base number. Generally this test is not used as a primary indicator when all other tests are within normal limits. Accurate oil information is required to get the most valid test results. Increase in sulphation generally correlates to a decrease in base number.
I hope this helps. If you need more info on the instruments and the ASTM methods used let me know. I dig this stuff!