Determining Water Separation of Aviation Turbine Fuel as per ASTM D3948

ByAamir Shahzad Butt

SCOPE & SIGNIFICANCE

The instrument provides a quick, portable means for field and laboratory use to rate the ability of aviation turbine fuels to release entrained or emulsified water when passed through fiberglass coalescence material.The test provides a measure of surface active materials in aviation turbine fuels. These are known to affect the ability of filter separators to separate free water from fuel.

APPARATUSMicro-SeparometerSix Pack Micro-Separometer kitMicropipette

Wire Aid

PREPARATION OF APPARATUS

• Unlock the box of WSIM apparatus by putting “000” on the lock and press

• Locate the instrument in an area where the temperature is between 18 °C and 29°C ± 3°C. Test performed outside of these temperature limits may not meet ASTM repeatability/reproducibility criteria.

• Open the case and remove the Six-Pack box from the lid. Insert your finger into the hole in the right panel and raise the panel until completely vertical and locked in place. If power is available, check to be certain the source voltage (220-260 volt power cord) matches the power cord label and connect the power cord.• Open a new six pack “syringe, ALUMICEL COALESCER, vial, plug, pipette tip, and a container for clean water.

• If the instrument is to be operated in a location where an AC outlet is not available, the instrument should be charged for approximately 16 hours before testing. The unit will function properly for approximately 25 tests before battery recharging is necessary.

PREPARATION OF SAMPLE

• Obtain and handle the samples with the utmost care and cleanliness as required in the ASTM Procedure D-3948. Before pouring the test sample from container, wipe the container outlet thoroughly with a clean, lintless wipe. Then pour the test sample into a clean beaker or directly into the syringe.• If the sample for test is not within the test temperature limits (18°C to 29°C) let the container stand or preferably put sample in a clean beaker and let it come to operating temperature.

PROCEDURE

• Press “ON” switch and warm up for at least 30 minutes.• Momentarily depress the "ON" switch. The annunciator lamps located

on switches A through G in the TEST SELECT section will then be scanning for your selection. Depress switch "A". This will initiate the standard automatic program for Jet A fuel.

• Note: Only JP 4 requires Mode B operation• Remove a plunger from a new 50-mL syringe and wipe the tip using a clean, lintless wipe to remove any sheen caused by excess lubricant. Insert a plug into the exit hole of the syringe barrel, add 50 ± 1 mL of fuel, and place the syringe barrel on the emulsifier mount, turning to lock in place. Ensure that the syringe barrel is properly aligned concentrically with the mixer shaft and is not touching the propeller.

Emulsifier mount

plug

Syringe Barrel

plungervial

ALUMICEL COALESCERpipette tip

Micropipette

Wire Aid

clean water

PROCEDURE• Add about 15 to 20 mL of the fuel to be tested into a new vial. Wipe

the outside of the vial with a clean, lintless wiper and insert the vial into the turbidimeter well aligning the black mark on the vial with the line on the front panel.• Initiate the CLEAN cycle by depressing the “START” pushbutton as designated by the annunciator light.

• Warnings—do not operate the mixer without having a syringe with fuel in place.Turbidimeter

Emulsifier mount and syringe barrel with fuel / Mixer

PROCEDURE• At the end of the first clean cycle, when the mixer motor stops, press

the RESET push-button, remove the syringe barrel from the emulsifier, discard the fuel, and drain the syringe thoroughly. Add 50 ± 1 mL of fresh fuel into the syringe and place the syringe barrel on the emulsifier mount (turn to lock in place). Visually inspect that the syringe barrel is properly aligned concentrically with the mixer shaft and is not touching the propeller. Select Test Mode A by pressing A push-button

• Initiate the second CLEAN cycle by depressing the “START” pushbutton as designated by the annunciator light.

• At the end of the clean cycle, when the mixer motor stops, remove the syringe barrel from the emulsifier, discard the fuel, and drain the syringe thoroughly. Add 50 ± 1 mL of fresh fuel into the syringe, add 50 μL of distilled water to the fuel sample. Place the syringe barrel on the emulsifier mount, With the syringe in place, depress the START push-button.

Water Addition depress the START push-button.

PROCEDURE• The automatic program starts with a read meter indication followed by

a 10-s full-scale adjustment period. During this period, the ARROWED pushbuttons will illuminate and can be depressed to adjust the meter to read 100. If the adjustment cannot be completed at this time, final adjustment can be accomplished during the second meter adjust period occurring later in the test sequence.• After the full-scale adjustment period the mixer motor activates and the emulsion process is initiated.

• When the mixer stops (after emulsification), remove the syringe barrel from the emulsifier and partially insert the. plunger to seal the open end of the syringe. Invert the syringe (exit hole up), remove the plug, and exhaust the entrapped air in the syringe barrel without significant fuel loss by carefully inserting plunger to the 50 mL mark. (Use a clean wipe over the exit hole to capture the small amounts of fuel which may be extruded as foam. Affix a new Alumicel coalescer to the end of the syringe barrel.

PROCEDURE• Place the entire syringe assembly into the syringe drive mechanism. To

minimize the effect of plunger resistance (drag) in the syringe barrel, align the syringe assembly vertically in the syringe drive mechanism with the end of the syringe plunger parallel with pushbar of the syringe drive mechanism. Position a waste container beneath the Alumicel coalescer to collect the unwanted portion of the processed fuel sample during the coalescing period.

Pushbar

• Collect the last 15 mL of fuel sample being processed from the Alumicel coalesce, when the collect sample annunciator lamp (marked C/S) illuminates and a pulsed tone of short duration sounds. To lessen the amount of air introduced into the fuel during this operation, position the vial at a slight angle and allow the fuel to flow down the inner surface. Remove the vial just prior to when the last amount of sample is expelled from the Alumicel coalescer.

Collect the last 15 mL of fuel sample

PROCEDURE• Wipe the outside of the vial with a clean, lintless wiper to remove any

fingerprints and fuel. Place the sample vial into the turbidimeter well aligning the marks on the vial and on the control panel in front of the well. At the end of the settling time (1 min), a steady (4-s duration) tone will alert the operator that the meter is about to activate

• At the end of the tone, the METER will automatically activate for approximately 10 s.

• MSEP ratings are read at the midpoint of the 10-s meter read cycle indicated by a short 1-s tone.

• Report the results obtained in hole number.