UNE-EN ISO 6246:2017

This International Standard specifies a method for the determination of the existent gum content of aviationfuels, and the gum content of motor gasolines or other volatile distillates. It includes the determination ofproducts containing alcohol (up to 85 % in volume) and ether type oxygenates and deposit control additives.For non-aviation fuels, a procedure for the determination of the heptane-insoluble portion of the residue is alsodescribed.CAUTION-This method is not intended for the testing of gasoline components, particularly thosewith a high percentage of low-boiling unsaturated compounds, as they may cause explosions duringevaporation.NOTE The true significance of this test method for determining gum in motor gasoline is not firmly established. It hasbeen proven that high gum content can cause induction-system deposits and sticking of intake valves, and in mostinstances it can be assumed that low gum content will ensure absence of induction-system difficulties. The user should,however, realize that the test is not of itself correlative to induction-system deposits. The primary purpose of the test, asapplied to motor gasoline, is the measurement of the oxidation products formed in the sample prior to or during thecomparatively mild conditions of the test procedure. Since many motor gasolines are purposely blended with non-volatileoils or additives, the heptane extraction step is necessary to remove these from the evaporation residue so that thedeleterious material, gum, may be determined. With respect to aviation turbine fuels, large quantities of gum are indicativeof contamination of fuel by higher boiling oils or particulate matter and generally reflect poor handling practices indistribution downstream of the refinery.