齿轮传动润滑技术交流.pptVIP

* * * * * * * There are three methods to extract a sample. The first is the SIMPLE method which uses either gravity or the machines lubrication pump to extract the oil. It is advisable with both these methods to allow some oil to drain away before taking the sample. Why?because there is often debris/contamination lodge around the sump plug / tap which could give a false impression of the oils condition. Care should be taken with this method in order to avoid any external dirt entry that can affect the accuracy of the sample results. Sample should be taken when oil is hot. As we have said before please make sure not to use the initial and final parts of oil stream, as these are not representative of oil in the equipment system. * * The second method is to use a drop tube EXTRACTION (vacuum) PUMP. This method allows you to take samples from engines, transmissions and other components by placing the plastic tubing into the dipstick access or other oil access opening and using the vacuum pump to draw oil into the sample bottle for testing. The best applications for this method are: Tank Reservoirs Crankcase oils ( often through the dipstick) In circulating systems take sample as close to the return line as possible In static tanks sample at the mid-point between oil level bottom, but always away from walls Sample during typical operating conditions Do not re-use tubes without first flushing thoroughly through with oil to be sampled For crankcase dipstick samples, cut tube about 10 inches (25 cms) longer than dipstick. Also cut end of tube at an angle to reduce risk of sampling sludge. Insert tube about ? inch (1? cms) shorter than dipstick. This ensures that tube does not touch the bottom of the sump thereby suck up unnecessary sludge/contaminants When bottle is ? full loosen bottle to release vacuum and stop flow. After sampling invert pump (with bottle removed) to allow oil in tube to drain back to sump. * * Once bottle has been filled with the used oil sample