OIL CONDITION MONITORING: AUTOMOTIVE ANALYSIS

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1 OIL CONDITION MONITORING: AUTOMOTIVE ANALYSIS Why Analyse Lubricants? With increasing costs and tighter deadlines, the need for effective maintenance strategies is greater than ever before. So why not start a condition monitoring program with the experts. At GB Lubricants and Fuels we have over 20 years of experience in monitoring all types of lubricated systems; whatever your business, we will be able to advise you on the condition of your oil and machinery. Q. Why use oil analysis? A. Regular oil analysis helps you to: Safely extend oil drain intervals Schedule maintenance Reduce downtime Extend warranties Q. What do we do? A. Using our Oil Condition Monitoring Program is simple, regardless of your business; by following 3 easy steps, your plant and equipment will be monitored with minimal fuss. Step 1: Step 2: Step 3: Taking Samples - Using the supplied kit (which may include a thief pump, tubing, sample bottle, instructions and information sheet), obtain a 100ml sample at oil drain time or routine service intervals. Dispatch sample to the GB Lubricants Laboratory. Sample Analysis - Once the sample has arrived at the lab, it will be registered, analysed, interpreted and reported within 5 working days. Results You will receive an analysis report in a format of your choice showing the condition of your sample. Reports are available via or hard copy. 1

2 Message in a Bottle The idea of using oil analysis as a commercial condition monitoring tool dates back to the 1940 s when railways in North America analysed engine oil to try and solve the problem of short engine life. However the real genesis of used oil analysis is from engine OEM s and oil companies who originally used it as a research and development tool. The basis of used oil analysis is SOAP Spectrometric Oil Analysis Program. Oil companies and independent laboratories introduced SOAP into Britain in the late 1960 s and it is now impossible to send a sample of for analysis without having some aspect of SOAP performed on the fluid. The principle of SOAP is quite simple and can be compared to a human blood test, whereby a small sample of the circulating fluid can give indepth readings into the health of the body it is servicing. Like a blood sample, a small amount of oil can show signs of contamination, degradation or wear and tear. In machinery, the oil sample will carry small particles of metallic debris, which can give indications of any wear patterns which may be occurring within the equipment. Using state-of-the-art instruments, we can determine the composition and concentration of these metallic particles and indicate which part of the machinery may be wearing at abnormal rates. Our experienced Chemists can then use the information generated by the laboratory to predict a potential problem with the oil or machinery before it becomes critical and long before in becomes evident to the maintenance engineer. 2

3 Engine Oil Analysis Service Safely Monitor your Engine Oils with our Bespoke Oil Analysis Program At GB Lubricants and Fuels, we have over 20 years experience of analysing oils from all types of engines. Whether your engine is powered by diesel or petrol, we offer a specific range of analytical tests to suit your requirements. Our testing ranges from basic contamination checks to full-blown engine oil condition analysis, whereby we perform lubricant condition checks to ascertain whether your engine oil is fit for further use. As well as routine testing including wear metals, viscosity and water, we offer the following tests which should be performed at least every 500 hours of operation on in-service engine oils: Our testing includes the following methods Kinematic Viscosity at 40 & 100 C: ASTM D892 Soot Content: ASTM E Water Content: Karl Fischer Method Diesel Dilution: GC Method Glycol Content: GC Method Base Number: IP276 Acid Number: ASTM D664 Oxidation: ASTM E Nitration: ASTM E

4 Engine Oil Analysis Methods Kinematic Viscosity: The resistance to flow is measured by the time taken for a given volume of oil, to flow under gravity between two points in a calibrated viscometer tube. Viscosity measurements are essential to establish the correct grade of oil is in use, e.g. SAE 20, 30 or 40. Viscosity can be affected by overheating, fuel dilution and other contaminants, polymer shear, over-use and if the wrong oil has been added. Soot: Soot is found in all used diesel engine oils and is a by-product of the combustion process. High levels of soot indicate abnormal blow-by occurring in the engine and will lead to several problems if not rectified, such as increase in viscosity duel to sludge formation, removal of additives and increase in wear particle generation. Diesel Dilution: These tests are essential to detect over rich mixtures, faulty injector systems and leaking pipework etc. Flash point & viscosity together are necessary to differentiate between fuel dilution, low viscosity oil contamination and polymer shear. An excess of fuel contamination can lead to poor lubrication and excessive wear or failure Glycol Content: Glycol is found in antifreeze/coolants and can enter the engine through various means. Blown head gaskets, damaged cooling system seals or cracked cylinder heads will all induce glycol into engine oil. Glycol contamination can increase wear rates drastically, increase an oils viscosity to reduce lubrication, react with additives to plug filters and block oil ways. Leaks can usually be found by pressure checking the cooling system. Oxidation: All oils will oxidise overtime when the anti-oxidant additives are used up keeping oxidation levels as low as possible will increase the life of the lubricant. Oxidation will measure the breakdown of a lubricant due to age and over-heating. It will attack additives and aid acid formation. Acid Number: Abnormal increases in oil acid levels may indicate severe oxidation or overheating of the oil. These acids can corrode metallic components but also further degrade the quality of the oil. Base Number: To protect the crankcase from acid attack by corrosive acids produced in the combustion chamber, the lubricant contains a degree of reserve alkalinity. This reserve alkalinity is expressed as mg of KOH/gm of oil and is described as the Base Number (BN). Water Content: The amount of water present in engine oils will reflect the potential for rust formation and reduction in additives. Therefore it is vital that these water concentrations are monitored and kept at low levels. Water can also cause sludge formation and affect the oil s viscosity. It can be derived from freshwater, seawater and anti-freeze 4

5 AdBlue Testing Services The process of Selective Catalytic Reduction (SCR) in vehicles requires a fluid to be added to the exhaust process to reduce nitrogen oxide emissions. This fluid is a water based liquid made up of a 32.5% solution of urea in demineralised water and it is colourless. The trade name for this fluid is AdBlue and it is carried on-board vehicles using SCR technology in a separate tank. AdBlue is added to SCR systems at a rate of between 3-5% of diesel consumption. The quality of AdBlue is paramount to the SCR system operating efficiently and must therefore comply with the recognised standard, ISO The test-suite performed will determine if the sample meets with the ISO specification and will also determine whether there is any significant contamination present. The measured parameters for AdBlue are as follows: TEST METHOD Min Limit Max Limit UNITS Urea content % MASS 20 o C g/cm 3 Refractive Index Appearance Visual Hydrocarbon dip paper Negative Positive Y/N Diesel Fuel Testing Check that fuel is fit for purpose Determine if fuel is contaminated Check condition of stored fuel before use Assist in investigation of fuel related failure Determine cause of fuel filter blockage Check for contamination of wrong fuel types, e.g. petrol% in diesel, etc Check Bio-fuel (FAME) content Check fuel is fit for use in cold climates Check for red diesel Specific and ad hoc testing Testing to international standards (EN590, BS2869 etc) 5

6 Diesel Test Methods Cloud Point (IP219) & Pour Point (IP15) When a fluid cools it to low temperatures in can no longer perform its primary functions. The lowest temperature at which a fluid flow and therefore can perform its functions in known as the pour point. Just prior to reaching the pour point the fluid becomes cloudy due to the crystallization of waxy constituents. The temperature at which the cloudy appearance is first seen is known as the cloud point. Using fluids at temperature below the cloud point can result in filter plugging and poor performance. Diesel fuel should have a cloud point of less than - 17 C. Copper Corrosion (IP154) Fluids working in an engine will always come into contact with metallic components made from copper or copper alloys. It is therefore essential that the fluids do not promote corrosion of the copper. Many oils and fuels contain Sulphur compounds, which can be corrosive to copper. Therefore this test is performed to see what levels of corrosion or tarnishing occurs when the fluid comes into contact with copper strips in the lab. Water in ppm (Karl Fischer Method) Any significant amount of water in a fuel system can be detrimental to the engine. Levels above 200ppm (0.02%) are considered abnormal. Contamination (IP440) Any significant amount of debris in a fuel system can be detrimental to the engine. Levels above 24mg/Litre are considered abnormal. Sulphur Content (ASTM D5185) New EN590 emission regulations state that diesel fuel does not contain greater than 0.005% sulphur. Therefore we analyse the fuel for sulphur content to ensure a content of less than 50ppm. Flashpoint (ASTM D93) When refined, all fluids are produced to have a certain flashpoint. This measures the fluids volatility and flammability. The flash point refers to the fluids minimum temperature at which there is sufficient vapour to cause a flash when a flame is introduced to the fluids vapour and air mixture. For example contamination with a more volatile fluid will decrease the fluids flashpoint. Diesel fuel should have a flashpoint greater than 52 C. 6

7 Diesel Test Methods Cetane Index (ASTM D976) By determining the mid boiling point by distillation (IP123) and the density of a fuel the cetane index can be calculated. This measures the ignition quality of a diesel fuel. The lower the cetane number, the more rapid the increase in ignition delay. Diesel fuel should have a cetane number greater than 40. Density (IP160) The mass to volume relationship of a fluid can be used to analyse a fluids composition uniformity. Density can also be used as a guide to hydrocarbon type. Diesel typically has a density between and Viscosity at 40 C (IP71) Viscosity measures the time it takes a fluid to flow under a specific temperature over a given distance in a capillary tube. Diesel typically has a viscosity between 1.6 and 5.8 Cst. Cold Filter Plugging Point (CFPP) (IP309) The Cold-Filter Plugging Point informs about possible trouble by precipitation of paraffin on filters at low temperatures. The Cold Filter Plugging Point is defined as the highest temperature (expressed as a multiple of 1 C) at which the fuel, when cooled under the prescribed conditions, either will not flow through the filter or requires more than 60 seconds for 20 ml to pass through. 7