ASTM D4305 Test Method for Filter Flow of Aviation Fuels at Low Temperatures
6. Apparatus
6.1 A detailed description is given in Annex A1.
6.2 The apparatus defined in this test method comprises a cooling/warming cell, a specimen pump, pressure sensor, test filter, syringe, sample filter, and associated electronic controls and displays.
7. Reagents and Materials
7.1 Heptane, technical grade.
NOTE 2 - Caution: Extremely flammable, vapor harmful if inhaled (see Annex A2.1).
7.2 Jet A or A1.
NOTE 3 - Caution: Combustible, vapor harmful (see Annex A2.2).
8. Sampling
8.1 Obtain a sample in accordance with Practice D4057.
8.2 Store the sample in a cool place (0 to 20°C) away from direct heat or sunlight.
9. Preparation of Apparatus
9.1 If the apparatus previously contained an unknown specimen, follow the manufacturer's instructions to clean the cell, using a paraffinic solvent such as heptane; oxygenated solvents such as acetone shall not be used as they may damage the cell. If the prior specimen is similar to the test material, the latter can be used to flush the cell.
9.2 The cleaning cycle shall be repeated at least twice, the last cycle involving flushing with the test material.
9.3 The cell temperature shall be warmer than 0°C before the test specimen is injected.
9.4 The syringe shall be clean and dry before use.
10. Calibration and Quality Control Checks
10.1 Follow the manufacturer's instructions.
10.1.1 Pressure Transducer - This should be checked once monthly by direct comparison with a water manometer, or a traceable pressure gage.
10.1.2 Specimen Pump - Calibration and operation of the pump should be checked once monthly.
10.1.3 Electronic Thermometer (PRT) - Calibration and operation of the PRT should be checked against a traceable standard every six months.
10.1.4 Control Sample - Confirm the calibration of the instrument each day it is used by running a control sample of known flow point.
