How to take a Sample. General instructions for correct oil sampling. Ensuring Health and Safety conditions. Ensuring the quality of the sample.

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1 How to take a Sample. Most lubricant condition monitoring services use an oil sample of only 100ml to represent a system that may hold hundreds or thousands of litres of oil. The importance of taking a representative sample cannot be over-emphasised. From the very first sample you begin investing in a valuable condition-monitoring programme. But this will only be achieved if every sample contributes to building an accurate history from which trends in wear, contamination, and degradation can be determined. General instructions for correct oil sampling Ensuring Health and Safety conditions. Always observe safety rules. Take particular care with high-pressure piping and thermal systems and any sampling close to electrical Equipment or when sampling from a drain line. If in doubt, please contact your Technical Advisor. Ensuring the quality of the sample. We recommend a consistent method of taking a sample. Always take the sample at the same point, in the same way and after the same amount of time. For example, if you previously took the sample half an hour after the machine has been started, please make sure that the next sample is taken half an hour after the start of the machine as well. We recommend that you sample a component while it is running (if it is safe to do so) or within 30 minutes after shutdown. Always keep in mind to refrain from sampling right after a large volume of lubricant has been added. Always be sure to draw sufficient of the sample to fill the bottle. 80% full is a good level to aim for as this will ensure that there is adequate sample to complete all tests and will ensure adequate ullage to allow sample agitation by the laboratory. Avoiding contamination of the sample. Areas where lubricant flow is restricted or where contaminants and wear products tend to settle/collect should be avoided as sampling points. Always take the sample in the most hygienic of conditions. In this way, you can avoid contaminating the sample, which could lead to an incorrect analysis. Always use the right sampling Equipment and the bottles supplied by Shell and make sure that they are unopened, unused and clean. Always clean the sampling kit immediately after use. After taking the samples, check to make sure that the bottles are tightly closed. It is important that the gun/bottle assembly is kept upright while in use to prevent oil entering the gun. Should this occur, disassemble it immediately and flush thoroughly with white spirit or kerosene. Dry before reassembling. DO NOT FLUSH GUN WITH PETROL OR DEGREASING FLUID. Sampling from circulation systems. For circulating systems one of the best sampling locations is a live zone upstream of filters where contaminants and wear debris are the most concentrated. Usually, this How to take a Sample Page 1 of 7

2 means sampling from fluid return lines or drain lines. For systems where oil drains back to a sump without being directed through a line (such as engines), draw from the pressure line down-stream of the pump (before the filter). Permanent sampling points should be at elbows in pipe runs in preference to straight sections. This will help to ensure that the flow regime at the sample point is turbulent and that wear and contaminant particles do not drop out of suspension. Sampling from reservoirs, sumps and tanks. Avoid sampling from dead zones of static tanks and reservoirs. In particular, sampling from the bottoms of sumps should be avoided because the wear debris and contaminants collected are likely to be the results of build up over time and may not represent current operating conditions. The sample point should be near the midpoint between the surface of the oil and the floor of the tank/sump and away from walls. Sampling from splash, slinger-ring and flood lubricated components. Splash, slinger-ring and flood-lubricated components are best sampled from drain plugs but only after considerable flushing. In a similar manner, permanent valves should be wiped clean and then flushed prior to sampling to ensure that any deadleg debris is excluded from the sample. Vacuum pump thief sampling. For thief sampling the Shell LubeAnalyst operator should follow the recommended instructions in order to ensure that representative samples are taken. Thief sampling utilises a vacuum pump and plastic tubing in order to draw samples via points such as dipstick tubes and filler plugs on gearboxes and transmission. When using a vacuum pump the oil does not make contact with the gun, consequently vacuum pumps are preferred over syringes. By comparison, syringes must either be flushed or replaced between samples in order to prevent crosscontamination. Tips for Successful Thief Sampling Tip 1: Cutting the bottom of the tubing at an angle of 45 degrees reduces the likelihood of drawing sludge from the bottom of sumps and tanks; Tip 2: Plastic tubing can be difficult to control once it enters a system via a filler plug. In order that the tube end does not draw oil from the sides or bottom of systems it may be necessary to use a custom made dipstick such that the tubing is clipped to the dipstick and the dipstick / tube combination is inserted into the system to be sampled. This should also prevent the uncontrolled sampling tube being fed into the path of meshing gear teeth. Care must be taken to ensure that the dipstick is thoroughly cleaned prior to sampling. Sampling from a heat transfer system. Please take note that for safety reasons taking oil samples from the heat transfer system it is important to note that the temperature of the oil could be over 100 degrees Celsius. If the correct guidelines are not followed it will be impossible to make a correct diagnosis. How to take a Sample Page 2 of 7

3 Always make sure that the oil has cooled before taking the sample. Always use aluminium bottles for taking the oil sample. Plastic containers are not appropriate because they tend to melt due to the high oil temperature. Always cap the bottles directly, so that the gases can t leak. Sampling Techniques & Frequencies Successful Oil Analysis Begins With Proper Sampling Sample Collection Successful oil analysis relies on proper sampling. Use proper sampling equipment Ensure bottle cleanliness (only use bottles provided by Shell) Practice uniform sampling technique & frequencies Minimise contamination due to poor handling Live sampling avoid dead zones Sample Point & Sampling Method Consistent samples should be drawn safely with relative ease. Examples of suitable sampling points: Engines.. dipstick into sump.. sample tap fitted to oil feed pipes Gearbox.. dipstick into sump.. level plugs Hydraulic Systems.. pressure and return lines, reservoir tap Compressors.. dipstick, sample tap.. sample tap fitted to oil feed pipes How to take a Sample Page 3 of 7

4 Sampling Simple Method Taking Oil From Sump Taking Oil from in line Tap How to take a Sample Page 4 of 7

5 Sampling Using Extractor Pump 1. Insert Pipe in dipstick Tube 2. Insert other end of tubing into extractor pump 3. Suck used oil into bottle How to take a Sample Page 5 of 7

6 4. Fill to Level Marked on the Bottle 5. Complete Shell LubeAnalyst Sample Registration Form or Complete on Shell LubeAnalyst Web 6. Stick on Label & Send Bottle with Sample Registration Form to Laboratory Shell LubeAnalyst How to take a Sample Page 6 of 7

7 Sampling Using Engine Valve Method This method assures the most representative sampling possible without shutting down equipment. It is also generally an easier, faster and cleaner method of sampling. The Engine Valve is permanently installed in any engine port, on a gearbox, or oil reservoir. The valve should be installed in a location where it is easy to access and before any in-line filtration system. Sample Dispatch To achieve the most accurate oil analysis results Send samples to the lab as soon as they are taken. How to take a Sample Page 7 of 7