ASTM D2711 standard test method for demulsibility characteristics of lubricating oils
5. Apparatus
5.1 Stirrer, constructed from parts shown in Fig. 1 and Fig. 2.
5.2 Special Graduated Separatory Funnel, as shown in Fig. 3.
5.3 Heating Bath, sufficiently large and deep to permit the immersion of at least two test separatory funnels in the bath liquid up to their 500-mL graduation mark. The bath shall be capable of maintaining a temperature of 82 more or less 1°C (180 more or less 2°F) and shall be so equipped to hold the separatory funnels securely in a position so that the vertical axis of the stirrer corresponds to the center line of the separatory funnel during the mixing of the oil and water.
5.4 Centrifuge, as described in Test Method D1796.
5.5 Centrifuge Tubes, long-form, 195 to 203 mm (8 in.) as described in Fig. 1 of Test Method D1796.
6. Materials
6.1 Cleaning Solvent - Any suitable solvent capable of cleaning and effectively removing any oil or fluid from the stirrer and graduated cylinder. 1,1,1-Trichloroethane has been found suitable for use in this test method. (Warning - 1,1,1-Trichloroethane, Harmful if inhaled or swallowed. Eye irritant. High concentration can cause unconsciousness or death.)
NOTE 1 - In cases in which the use of 1,1,1 trichloroethane is unacceptable, some laboratories are using heptane or mineral spirits as alternative solvents. The effect on the precision of this test method when using an alternate solvent has not been determined.
6.2 Water - Type II reagent grade water conforming to Specification D1193.
7. Preparation of Apparatus
7.1 Clean the graduated separatory funnel by removing any film of oil with cleaning solvent followed by a wash first with acetone (Warning - Extremely flammable vapors may cause flash fires.) and then with tap water. Rinse thoroughly with tap water and then with reagent grade water.
7.2 Clean the stirrer by appropriate means, using the cleaning solvent (6.1). Allow the stirrer to air dry completely prior to use in the test.
