Diesel fuels. Cold filter method for determination of lowest filtering temperature
The scope of the method consists in gradual cooling of the test fuel at intervals of 1 °C and draining it through a wire filter mesh at a vacuum of 1961 Pa (200 mm of water column) [20 mbar].
The State Standard GOST 22254 establishes a method for determining the limiting filterability temperature on a cold filter for diesel and household heating oils intended for the national economy and for export.
The method applies to diesel fuels with and without additives, as well as fuels used in domestic heating systems.
The determination is carried out until the temperature at which the wax crystals separated from the solution onto the filter cause the flow to stop or slow down to such an extent that the filling time of the pipette exceeds 60 s, or the fuel does not completely flow back into the measuring vessel.