Applications of particle counters are separated into three primary categories:• Aerosol particle counters• Liquid particle counters
Most fluid sample labs can carry out analysis onfuel, oil, water, coolants, etc. which may includebut not limited to one of the following:Spectrographic analysis of wear metals, oiladditives, contaminants. These analyses focusmore on wear elements. It identifies andquantifies the elemental constituents present inthe oil in parts per million, i.e. about 10 to 15microns in size.
Particle count may be performed to determinepresence of large metal particles in hydraulic andtransmissions applications. It could also quantify anytype of particle metals and non-metals, from onemicron to 200 microns in size.TAN (Total Acid Number) and TBN (Total Base Number):Testing is a measure of acidity within oil. It indicatesthe acid-neutralizing capacity still in the lubricant andis particularly important for engine oil, as it iscontinuously exposed to acidic combustion productsand these must be neutralised before they corrodeengine parts.
Taking an Oil Sample Analysis result will be based only on the sample that you send in for analysis. Run equipment or engine to operating temperature to ensure the oil is hot and thoroughly mixed before sampling. The fluid testing lab will provide you with the sampling kit.Basically, oil samples can be taken by two methods:1. Valve sampling2. Vacuum extraction
Valve sampling method: In this method a sampling pointon the system must be in place or can be installed. Run theengine at low idle until it reaches normal operatingtemperature. Remove the dust cap from the samplingvalve of the compartment and wipe clean. With themachine still running, insert the sampling probe into thevalve and draw a small amount of oil into a waste oilcontainer for disposal, then proceed to fill sample bottlefrom the sampling point to about three-quarters full or thelevel specified by the oil testing lab. Remove the probeand replace the dust cap and secure the cap on the bottle.Label the sample ready for shipping or to be tested in yourcompany’s lab.
Vacuum extraction: For systems without a sample point on the machine, run the system or engine to operating temperature and then stop the engine. Measure and cut new tubing to the length of the dipstick or to such a length that it reaches about halfway into the fluid depth of the given compartment. Using a vacuum pump, insert the measured plastic tubing into the pump and attach the sample bottle. Insert tubing into dipstick hole or the compartment and draw off the sample. Remove the tubing from the bottle and the vacuum pump and secure the cap on the bottle. Label the sample ready for shipping or to be tested in your company’s lab.
Labeling Sample• Each sample submitted, must have the following information on the sample bottle:• Owner or company’s name.• Fleet or Unit Number of Machine• Machine Make, Model and Manufacturer’s name• Compartment from which the sample was taken• Number of Hours on Sample.• Date the Sample was taken• Oil change and oil added• Oil type and brand of oil• Viscosity• Any other comment can be added
Sample Result The sample analysis result will include a list of wear element present and the condition of the physical property of the fluid. The analysis report will compare the test data to a new fluid baseline results. Instant notifications are usually given for samples with excessive metal, particle contamination, fuel dilution or any other serious issues resulting from the test.
Test elementsThe follow elements are tested for and are usually included in analysis of a sample result:• Silicon (Si): High Si readings generally indicate dirt or fine sand ingestion through air intake system, oil filter plugging, oil filler cap, breather, valve covers, oil supply etc. This would act as an abrasive, causing excessive wear.• Aluminum (Al): High readings can be from thrust washers, bearings and pistons which are made of this metal. Dirt ingestion through air intake system, oil filter plugging, oil filler cap and breather, valve covers, oil supply etc. may cause piston skirt erosion, enlarged ring groove, thrust washers wear, etc.• Lead (Pb): Bearing corrosion or wear will result in very high Pb test result. Extended oil change intervals, use of leaded fuel, dirt intake are associated with bearing wear. The indicators may be an abnormal engine noise or oil pressure, fuel dilution, etc.• Boron, Barium, Calcium, Magnesium, Phosphorous, and Zinc: These elements are usually added to fluids in the form of additives to improve their properties as a detergents, dispersants, anti-foam, anti-rust, etc. An acceptable level of these additives is necessary to guaranty the fluid property to perform its intended function.• Chromium (CR): High levels of (Cr) can be caused by dirt entry through the air intake or broken rings. Excessive oil blow-by and oil consumption, oil degradation are normally associated with broken piston rings or wear.• Silver (Ag) and Tin (Sn) will indicate wear of bearings resulting in excessive oil consumption, abnormal engine noise, loss in oil pressure, etc.• Iron (Fe): High (Fe) reading indicate wear of cylinder liner, camshafts, crankshaft, valve and gear train, oil pump, rust in system, stuck or broken piston rings, etc. and may be signalled by excessive oil consumption, abnormal engine noise, performance problems, abnormal operating temperatures or oil pressure, etc.• Copper (CU): High (Cu) reading will be from bearings, bushings and valve guide wear, etc. resulting in abnormal engine noise, oil pressure, fuel dilution, coolant in engine oil, etc. The likely cause will be dirt intake, extended oil change intervals, oil cooler failure, radiator corrosion, etc.• Sodium (Na): High Na readings are normally associated with a coolant leak in the system.
Physical Test In addition to the elemental analysis, physical test results from particle, magnetic test, etc. may be included.Failure analysis Failure analysis must be carried out on failed components or parts to ascertain the root cause of a problem with a view of eliminating or preventing future occurrence.