Mechanical Impurities

Description

A gravimetric method for determining the amount of insoluble solid particles (dust, metal, soot) in petroleum products that cause abrasive wear.

Solid mechanical impurities are the «invisible killers» of your equipment. Sand, dust, rust particles, or metal shavings circulating in the lubrication system act like sandpaper, instantly destroying precision plunger pairs in hydraulics, turbine bearings, and fuel injectors. Mechanical impurities analysis at the RENA laboratory allows you to measure the exact weight of this «garbage» in the fluid and save your machinery from premature major overhauls. This test is fundamental both for assessing the cleanliness of fresh oil and for monitoring the efficiency of oil filters. The test (GOST 6370) is performed using a classic but extremely precise gravimetric (weighing) method. First, an ashless paper filter is prepared: it is dried in a LabExpert 3100 MC drying oven to a constant mass and weighed on RADWAG analytical balances with an accuracy of 0.0001 grams. The tested oil sample (about 100 grams) is dissolved in a hot solvent (solvent naphtha or toluene) to minimize the fluid's viscosity. The resulting mixture is filtered through the prepared filter using a glass funnel. After that, the filter with the residue is thoroughly washed with pure solvent until no traces of oil remain. Then the filter is placed back into the drying oven (at 105 °C) to evaporate the remaining solvent, cooled in a desiccator, and re-weighed. The difference between the final and initial mass of the filter, divided by the mass of the taken sample, gives the exact mechanical impurities content in percent.