SH/T 0616-1995 Determination of Water Separation Index of Jet Fuels (Portable Separator Method)

AI-translated method card — human verification pending. This is not an official translation of the standard. Unclear source values remain unverified; check the original standard and product certificate before use.

Card type: Test method

1. Method number / full title / English name / replacement relationship

• Standard number: SH/T 0616-95
• Chinese full title: Determination of Water Separation Index of Jet Fuels (Portable Separator Method)
• English name: not provided in the available source
• Replacement relationship: not provided in the available source (the source does not mention a replaced standard)
• Adoption relationship: equivalent adoption of the American Society for Testing and Materials standard ASTM D3948-93 "Standard Test Method for Determining Water Separation Characteristics of Aviation Turbine Fuels by Portable Separometer" (see additional notes)
• Issued/implemented: issued by 1995-06-15, implemented by 1995-10-01; issued by China Petrochemical Corporation

2. Scope of application and non-applicability

• This standard specifies the determination method for the water separation index of jet fuels.
• Applicable to 1 jet fuel, 2 jet fuel, 3 jet fuel, wide-cut jet fuel and high flash point jet fuel with a water separation index of 50~100.
• 4.3: The range for determining the water separation index with the micro separometer is 50–100; measurement results outside the range 50–100 are considered unreliable and invalid; if the measurement result is greater than 100, it is very likely that the test sample removed substances from the fuel that weaken light transmission during the coalescence process, and the light transmittance of the tested fuel is higher than that of the reference fuel with a light transmittance of 100.
• Non-applicable: the source does not clearly list non-applicable clauses (except that exceeding the range 50~100 as above is invalid).

3. Method principle

• 5 Method summary: The test is carried out using a portable micro separometer. The emulsification of water and fuel sample is performed in a syringe using a high-speed mixer. Subsequently, the emulsion is pushed out of the syringe at a predetermined rate through a standard glass fiber coalescer, and the light transmittance of the effluent fuel is measured to determine the water separation index of the jet fuel. The light transmittance value is expressed as a number from 0–100 and reported to the nearest integer. A high light transmittance value indicates that water in the fuel is easily coalesced, meaning the fuel contains fewer surface-active substances; conversely, it contains more. The test is completed within 5–10 min.
• 3.1 Terminology: Micro separometer rating MSEP (Micro Separometer rating), the value finally displayed by the test indicates the ease or difficulty with which emulsified water coalesces and separates from the fuel under the influence of surface-active substances (surfactants). The MSEP rating results obtained by test mode A and test mode B are called MSEP-A and MSEP-B respectively, and can be compared with GB/T 11129, with the same rating results.
• 4.4: The basic difference between the two test modes A and B is that the flow rate at which the emulsion of water and fuel is pressed through the standard glass fiber coalescer is different, that is, the time required for the emulsion to pass through the coalescer is different. Mode A is 45±2 s, and mode B is 25±1 s.

4. Reagents and materials (purity / preparation)

• 6.1.1 Aerosol OT, solid (100% dry agent): sodium di-2-ethylhexyl sulfosuccinate. Prepare a toluene solution of 1 mg aerosol OT/mL for use as a dispersant. Preparation method: weigh aerosol OT 0.1 g (weigh to 0.0002 g), dissolve in small portions of toluene several times and transfer to a 100 mL brown volumetric flask, then dilute to the mark with toluene, shake well and set aside.
• 6.1.2 Toluene: analytical reagent. Note: flammable, vapor toxic.
• 6.2.1 Reference base fluid: a clean hydrocarbon fuel containing no surfactants, used to check whether the operation is appropriate and to calibrate the instrument. The preparation method is detailed in Appendix A. Note: flammable, vapor toxic. Note: The reference base fluid is required to have no dispersant added, and its standard is that the MSEP rating result is 99 or above 99; use it to calibrate the instrument. If the measurement result does not reach 99, it indicates that the instrument precision is insufficient, and the data obtained outside the measurement range 50~100 are invalid.
• 6.2.2 Water: clean, distilled, surfactant-free water.
• 3.2 Reference liquid: fuel treated with 5% (m/m) activated clay (activated at 120 ℃ for 4 h), if necessary also washed with water and treated with a filter separator, and then added with a certain amount of known surfactant (typically a toluene solution of sodium di-2-ethylhexyl sulfosuccinate).
• 8.2.3 Diluted dispersant solution: for field use, a diluted dispersant solution (prepared according to 6.1.1), a reference base fluid (prepared according to Appendix A) and distilled water can be used to complete the MSEP test to verify the instrument. The diluted solution is 10:1 diluted solution, prepared by diluting 10 mL dispersant with 90 mL toluene (6.1.2); 1 mL diluted solution is equivalent to 0.1 mL dispersant. When 50 μL diluted solution is added to 50 mL reference base fluid, the dispersant concentration is 0.1 mL/L.
• Appendix A3.1 Activated clay: first-grade product.

5. Instruments and equipment

• 7.1 Portable Mark V Deluxe 1140 type micro separometer or a domestically produced instrument with the same function that has been appraised.
• 7.1.1 The micro separometer is completely portable and self-contained. It can operate on AC power or internal rechargeable battery. Different detachable power cords are used for different voltages. AC power can supply power to the instrument or charge the rechargeable battery. The accessories and consumable materials required for six tests are all stored in a lockable instrument case.
• 7.1.2 The overall view and control panel of the Mark V Deluxe 1140 type micro separometer are shown in Figure 1. The emulsifier is on the right side of the vertical panel, the syringe pushing mechanism is on its left side, and the control panel is mounted on the fixed plate on the left side inside the case. Table 2 lists the manual and automatic operating features of the instrument.
• 7.1.3 All control keys are arranged as buttons on the control panel. When a button is pressed, the light turns on, indicating the operating status. A circuit breaker fixed on the control panel provides protection for the AC circuit.
• 7.1.4 Press the ON button to connect the circuit. When operating on AC power, the ON button indicator flashes; when operating on the internal rechargeable battery, the indicator stays on. The lettered button indicators flash continuously, indicating that the operating status is ready and test mode selection can be performed. Note: Among the buttons labeled with letters A~G, only the A and B buttons are applicable to this standard method.
• 7.1.5 The RESET button can be pressed at any time to cancel the ongoing test and restore the program to the initial mode.
• 7.1.6 The selection of test mode A and B programs is accomplished by pressing the A or B button.
• 7.1.7 When the START button is initially pressed, the syringe cleaning process begins, the emulsifier motor performs the cleaning operation, and at the same time the syringe pushing device is moved upward.
• 7.1.8 After the cleaning process, press the START button to start the automatic process. The reading display and the two + arrow buttons light up, indicating that the full-scale adjustment stage can be entered (see Table 3 test procedure).
• 7.1.9 The turbidimeter is located below the main control panel and consists of a cell for placing the straight-neck bottle, a light source and a photocell.
• 7.1.10 Press the appropriate + arrow button to increase or decrease the displayed value as required, so that the fuel sample in the turbidimeter cell obtains a reference level of 100.
• 7.2 Auxiliary equipment and consumable materials:
  • 7.2.1 Syringe plug: a plastic plug used to plug the syringe during cleaning and emulsification to prevent oil leakage.
  • 7.2.2 Syringe: made of plastic, consisting of a syringe barrel and a plunger.
  • 7.2.3 Straight-neck bottle: a glass bottle with an outer diameter of 25 mm, with a suitable mark pre-marked on the bottle mouth for placement in the turbidimeter cell.
  • 7.2.4 Aluminum coalescer: marked for jet fuel, consumable, pre-calibrated, and with a tip that matches the syringe.
  • 7.2.5 Micro syringe: 50 μL, calibrated, total capacity error less than 5%.
  • 7.2.6 Assist wire: a piece of metal wire with a ring at one end, used during the test to release gas trapped above the sample in the syringe barrel when the plunger is inserted. Each micro water separometer is provided with one assist wire.
  • 7.2.7 Plastic container: provided with each micro separometer, used to collect waste fuel during the coalescence test stage.
  • 7.2.8 Water container: a clean container for distilled water.
  • 7.2.9 Graduated cylinder: 50 mL, used for sampling during the test.
  • 7.2.10 A new syringe, straight-neck bottle, syringe plug and aluminum coalescer are used for each test. These consumable materials are packed in a box for six tests, and the box is fixed in the top cover of the micro separometer (see Figure 2). Note: The syringe, aluminum coalescer and other accessories used for each test may also be domestically appraised products.
  • 7.2.11 Pipettes: one each of 100 mL and 10 mL.
• Appendix A4 Equipment: A4.1 feed container (a square or round glass or iron drum capable of holding fuel oil, at least capable of holding 5 L fuel oil); A4.2 sample bottle (capacity 5 L, clean, capable of receiving fuel after clay filtration); A4.3 graduated cylinder (2 L); A4.4 funnel; A4.5 industrial filter paper.
• Adoption note 1): Replace the biological pipette G tube and its plastic clip F in ASTM D3948 with a 50 μL micro syringe.

6. Recommended operating conditions

• 8.1.2 Place the instrument on a clean workbench, with the ambient temperature between 18~29 ℃ and a variation not exceeding ±3 ℃.
• 8.1.3 Open the box, lift the right side panel to fully vertical and lock it. If AC power is available, select a different power cord according to the voltage and connect the instrument. If using internal battery power, ensure the rechargeable battery has enough charge to perform the required number of tests. If the power light does not come on, it indicates the battery power is insufficient; the instrument should be connected to AC power to charge before use 16 h, which is approximately enough for the power needed for 25 tests.
• 8.1.4 Turn on the power by pressing the button switch marked ON. When the instrument is connected to AC power, the ON power indicator light should flash; when operating with the internal rechargeable battery, this indicator light should remain steadily lit. During a test operated with the internal rechargeable battery, if the power indicator light flashes, it indicates that the battery must be recharged.
• 8.1.6 The advancement time of the syringe pusher during the coalescence test stage is initially calibrated at the factory for each mode of operation; the advancement time has an important influence on the final test result. When using test mode A or B, the advancement time of the syringe pusher during the coalescence test stage should be within the range of 45±2 s or 25±1 s, respectively. If it is not within the range of 45±2 s or 25±1 s, the instrument may be returned to the factory for adjustment. Note: If the advancement time of the syringe pusher exceeds the upper limit, it will cause the final result to be high; conversely, if the advancement time is below the lower limit, it will cause the final result to be low.
• 8.1.7 Mark V Deluxe 1140 model micro-separator has a self-check circuit to detect the situation where the advancement time of the syringe pusher exceeds the limit. The alarm indicator light (marked SYR) lights up with the out-of-limit condition (exceeding 3 s), and at the same time three short sounds are emitted (1 s). Occasionally an out-of-limit alarm may occur during a test; this does not indicate that the instrument is in poor condition. If repeated alarms occur many times, the instrument should be returned to the factory for adjustment.
• 4.5 / Table 1 Applicable test modes for different jet fuels:
  • 1 jet fuel: A
  • 2 jet fuel: A
  • 3 jet fuel: A
  • High flash point jet fuel: A
  • Wide-cut jet fuel: B
• 4.6 Mode A is applicable to 1, 2, 3 jet fuels and high flash point jet fuel, and its evaluation results are almost the same as the evaluation results of GB/T 11129.
• 4.7 Mode B is applicable to wide-cut jet fuel, and its evaluation results are almost the same as the evaluation results of GB/T 11129.
• Table 3 Test procedure (time/action, source-text extraction table, some values require confirmation against the source standard):
  • Mode A timing: 0:14, 0:44, 1:14, 1:18, 1:28, 2:13, 3:09, 3:13, 3:18, 3:23 (requires confirmation against the source standard (source-text extraction))
  • Mode B timing: 0:14, 0:44, 1:14, 1:18, 1:28, 1:53, 2:49, 2:53, 2:58, 3:03 (requires confirmation against the source standard (source-text extraction))
  • Program time (s) column appears: 4, 10, 30, 30, 4, 10, 45 (Mode A); 4, 10, 30, 30, 4, 25 (Mode B) (requires confirmation against the source standard (source-text extraction))
  • Action/operator action: start program (press start switch), pulse sound, prepare to read, reading starts, full-scale adjustment 1, emulsification starts (observe emulsification, no action, place emulsified sample into syringe pusher), pulse sound, prepare to read, reading starts, full-scale adjustment 2, syringe pusher, coalescence stage collection, start descending, sample (no action, place sample into turbidimeter cell), continuous sound, prepare to read, reading starts, read result, 1 s signal sound, record result.

7. Sampling and specimen preparation

• 9.1 The test sample must not be pre-filtered, because the filter medium may remove many surfactants, which are exactly what this standard is intended to detect. If the test sample is contaminated with particulate matter, these substances should be precipitated out of the test sample before testing.
• 9.2 Whether placed directly into the test syringe or into a sample container, sampling must be done very carefully and kept clean. Before pouring the test sample from the container, thoroughly wipe the container outlet with a clean, lint-free cloth, and pour the test sample into a clean beaker or directly into the syringe barrel. Note: Test results are very sensitive to trace contaminants from the sampling container; it is recommended that the sampling container used meet the requirements of Appendix B.
• 9.3 If the test sample is not within the range of test temperature 18~29 ℃, it is permitted to let the sample stand until it reaches the test temperature range.
• Appendix B Sampling container (reference):
  • B1.1 It is best to choose an epoxy resin-lined container; after rinsing three times with the sample to be taken, it can be used directly or used for sample storage.
  • B1.1.1 Used containers must be cleaned with 1,1,2-trichloro-1,2,2-trifluoroethane (fill the container to 10%~20% with this solvent, rinse three times in this way; each rinse the container should be closed and shaken 1 min, then change the solvent for the next rinse; after the final rinse solvent is drained, the container should be air-dried) before they can be reused.
  • B1.1.2 If samples of the same type of fuel containing the same additives are to be taken, the preparation is to rinse the container three times with this new sample.
  • B1.2 Hard strip-shaped polyethylene bottles may be used.
  • B2 Polytetrafluoroethylene bottles have not been evaluated, but may be satisfactory after cleaning with trichlorotrifluoroethane in accordance with B1.1.1.
• Appendix A Preparation of reference base liquid (supplementary):
  • A1.1 Describes a rapid and simple method for preparing a reference base liquid in the laboratory, which can obtain a filtrate with a MSEP rating of 99.
  • A2 Process overview: Take jet fuel distillate (without additives), add 5% (m/m) activated clay (activated at 120 ℃ for 4 h), stir for 30 min, after settling filter the upper clear liquid with filter paper and store in a bottle for later use, discard the clay at the bottom.
  • A5 Filtration procedure: A5.1 Dry the activated clay at 120 ℃ for 4 h; A5.2 Measure 5 L jet fuel distillate and weigh it; A5.3 Calculate the required amount of activated clay based on the mass of the jet fuel distillate [amount is 5% (m/m)]; A5.4 First add the jet fuel distillate to the stirring container, then add the activated clay in the calculated amount, stir for 30 min, settle for 30 min; A5.5 Use a funnel with industrial filter paper to filter the clay-treated base fuel into a sample bottle, to be used as reference base liquid, and discard the remaining clay.

8. Analysis procedure

• 10.1 Select Mode A or Mode B for operation.
• 10.1.1 Turn on the power, press the ON button to turn on the circuit. Then operate according to the selected Mode A or Mode B, press the corresponding A button or B button; the continuously flashing button will stop, and the pressed button will also stop flashing, indicating that test mode A or B has been selected, and the correct syringe pusher speed is automatically set.
• 10.2 Pull the plunger out of a new 50 mL syringe, insert the syringe plug into the bottom of the syringe barrel cone, add about 50 mL test sample into the syringe barrel, place the syringe and barrel on the emulsifier rack and rotate to lock. Ensure that the syringe barrel is exactly on the same axis as the stirrer and does not touch the stirring paddle.
• 10.3 Press the START button, and the cleaning process begins. Note: The syringe containing the test sample must be installed in place as required by 10.2 before the stirrer can be started. The stirrer bearing is lubricated by fuel.
• 10.4 Use a graduated cylinder to take about 15~20 mL test sample and add it to a new straight-neck bottle, wipe the outside of the bottle with a clean lint-free cloth, and insert it into the turbidimeter cell so that the black mark on the bottle aligns with the scribed line on the control panel.
• 10.5 At the end of the cleaning process, when the stirring motor stops rotating, remove the syringe barrel from the emulsifier, pour out the test sample in it, and thoroughly drain the test sample from the syringe barrel, then accurately measure 50 mL test sample according to the 50 mL scribed line marked on the syringe barrel.
• 10.6 When holding the syringe barrel by hand, the test sample should be heated by body temperature as little as possible.
• 10.7 Use a 50 μL microsyringe to transfer 50 μL distilled water and add it to the test sample in the syringe barrel, so that the tip of the microsyringe needle is just immersed below the liquid surface of the test sample at the center of the syringe barrel, to ensure that the water droplet is completely discharged and sinks to the bottom.
• 10.8 Place the syringe barrel on the emulsifier rack and rotate to lock.
• 10.8.1 Ensure that the syringe barrel is exactly in a concentric straight line with the stirrer shaft. Whether it is in a straight line can be checked by holding the syringe barrel and rotating it until the propeller at the end of the stirrer does not touch the wall of the syringe barrel. Failure to be in a straight line can cause the formation of plastic shavings, which are collected on the aluminum coalescer filter material and cause erroneous test results.
• 10.9 When the syringe is in place, press the START button, and the automatic part of the applicable test mode procedure listed in Table 3 begins. If for any reason you want to interrupt the procedure and restart the test, pressing the RESET button will cancel the test process and restore it to the start test procedure.
• 10.10 The automatic procedure begins with the reading indication (four short sounds), followed by the 10 s full-scale adjustment stage. In this stage, use the button marked with the + arrow to adjust the reading to 100. When the value is lower than 100, press the - arrow button to adjust; when the value is higher than 100, press the + arrow button to adjust, until the displayed reading is 100. If the adjustment is not completed at this time, the final adjustment can be completed in the second reading adjustment stage of the subsequent test process.
• 10.11 After the full-scale adjustment stage, the stirring motor automatically starts, and the emulsification process begins. Note: During high-speed emulsification, a few drops of test sample may leak from the hole in the head of the emulsifier; this does not affect the test result.
• 10.12 After the stirring stops and its emulsification process ends, remove the syringe from the emulsifier, partially insert the plunger, and by using a helper wire or inverting the syringe, release the residual air above the test sample in the syringe barrel without significant loss of the test sample, then replace the plug with an aluminum coalescer, and place this complete assembly on the syringe drive mechanism.
• 10.12.1 Method for expelling residual air from the syringe barrel using a helper wire: before inserting the plunger, place the helper wire into the syringe barrel, hold the upper part of the syringe barrel by hand so that the syringe and the helper wire form an acute angle, insert and press the plunger to the 50 mL mark on the syringe barrel, releasing the residual air therein. Quickly pull the helper wire out of the syringe, then remove the plug from the lower end of the syringe and replace it with an aluminum coalescer.
• 10.12.2 Method for expelling residual air from the syringe by inverting the syringe: insert the plunger, then invert the syringe (tip upward), remove the plug from the syringe tip, push or press the plunger to the 50 mL mark on the syringe barrel, so that the residual air in the syringe barrel is completely expelled through the hole at the syringe tip, then secure an aluminum coalescer to the end of the syringe.
• 10.12.3 The entire sequence of actions for the above two air expulsion methods must be completed within the specified time (30 s), and this entire set of syringe components must be placed into the syringe drive mechanism (otherwise invalid). To minimize the resistance of the plunger in the syringe barrel, align the syringe assembly vertically with the syringe drive mechanism. Place a plastic container below the aluminum coalescer to collect the portion of the test sample not wanted during the coalescence stage.
• 10.12.4 Each instrument is provided with a grounding wire; connect it to the micro-separator to prevent static electricity from causing ignition of the flammable test sample. One end has an alligator clip, and the other end has a banana plug. Clip the alligator clip to the aluminum coalescer, and insert the banana plug into the grounding hole on the casing.
• 10.13 Four short sounds indicate the start of the second reading adjustment stage. If necessary, the operator can use the button marked with a + arrow to adjust the measured value to 100. At the end of the measurement adjustment stage, the syringe drive mechanism will begin to run downward, pressing the emulsion of water and test sample through the aluminum coalescer. During this operation, remove the straight-neck bottle from the turbidimeter cell and discard the test sample therein, in preparation for collecting the final 15 mL test sample.
• 10.14 When the collect test sample indicator light (marked C/S) flashes and emits a short continuous pulsing sound, it indicates that the time has come to collect the final 15 mL test sample. Use the straight-neck bottle to collect this final 15 mL test sample filtered through the aluminum coalescer. To reduce the amount of air introduced into the test sample during this operation, tilt the straight-neck bottle at a small angle so that the test sample flows down along the inner surface. When the last portion of the test sample has drained from the aluminum coalescer, remove the straight-neck bottle.
• 10.15 Wipe the exterior of the straight-neck bottle with a clean, lint-free cloth to remove fingerprints and test sample remaining on the exterior of the straight-neck bottle. Place the straight-neck bottle into the turbidimeter cell, and align the mark on the straight-neck bottle with the mark in front of the cell on the control panel. At the end of the settling time (1 min), a continuous sound (continuous 4 s) will remind the operator to take a reading.
• 10.16 At the end of the sound, the measurement is automatically performed for approximately 10 s.
• 10.16.1 MSEP The rating result is read out during the 10 s measurement reading process, prompted by short 1 s sounds. The reading after the second sound is taken as the single test result.
• 8.2 Preparation of reference liquid:
  • 8.2.1 To verify the operating performance of the micro-separator, a reference liquid must be prepared. The preparation method is to quantitatively pipette 0.2, 0.4, 0.6, 0.8, 1.0, and 1.2 mL dispersant, and add them respectively to each prepared 1 L reference base liquid. The MSEP-A rating results applicable to 1, 2, 3 jet fuels and high flash point jet fuel are shown in Table 4; the MSEP-B rating results applicable to wide-cut jet fuel are shown in Table 5. The reference liquid should be tested using the corresponding operating mode as described in Chapter 10. If the rating result is not within the limits listed in Table 4 or Table 5, the reference liquid should be discarded, and a new reference liquid should be prepared and the determination repeated. If the repeated test exceeds the permitted test results, the instrument should be returned to the manufacturer for adjustment and calibration.
  • 8.2.2 As described in 8.2.1, add the dispersant to the reference base liquid to prepare the reference liquid. Note: ① Do not use adsorptive containers to hold the reference liquid, because the additive may be adsorbed by the container walls, and the MSEP rating result may increase significantly. Considering the influence of the inner wall of the container, the reference liquid can be stored for at most 24 h. ② For new instruments, after replacement of major parts, and when abnormalities occur, verification with the reference liquid must be carried out, and only when the results meet the requirements of Table 4 or Table 5 may the test sample be determined.
  • 8.2.3 Diluted dispersant solution: For field use, a diluted dispersant solution (prepared according to 6.1.1), a reference base liquid (prepared according to Appendix A), and distilled water can be used to complete the MSEP test to calibrate the instrument. The diluted dispersant solution is a 10:1 dilution, prepared by diluting 10 mL dispersant with 90 mL toluene (6.1.2). Therefore, a 1 mL dilution is equivalent to 0.1 mL dispersant. When the above 50 μL dilution is added to 50 mL reference base liquid, the dispersant concentration in the reference base liquid is 0.1 mL/L (1 L reference base liquid contains 0.1 mL dispersant). The various dispersant concentrations listed in Table 4 and Table 5 are all equal multiples of 0.1 mL/L. Just as the MSEP test requires a 50 μL microsyringe to add distilled water, use a 50 μL microsyringe to draw 0.1 mL/L of the dilution in several portions to prepare reference liquids with different dispersant concentrations as listed in Table 4 and Table 5. According to the reference liquid concentration data listed in the tables, compare the MSEP rating results with the corresponding results listed in the tables.
• 8.1.5 Prepare the required syringes, straight-neck bottles, aluminum coalescers, syringe plugs, microsyringes, helper wires, and clean containers containing distilled water.

9. Qualitative and Quantitative and Calculation Formulas

• 10.16.1 MSEP The rating result is read out during the 10 s measurement reading process, prompted by short 1 s sounds. The reading after the second sound is taken as the single test result.
• 12.1 Report the results measured in 10.16.1; for mode A operation report the MSEP-A rating result; for mode B operation report the MSEP-B rating result.
• 12.2 Take the arithmetic mean of the two results of duplicate determinations as the test result.
• The transmittance value is expressed as a value from 0 to 100, and reported to the nearest integer (see Chapter 5).
• Calculation formula: not provided in the available source (the source does not give a calculation formula).

10. Precision

• 11.1 Judge the reliability of the test results using mode A according to the following provisions (95% confidence level).
  • 11.1.1 Repeatability: In the same laboratory, by the same operator, using the same instrument, two successive tests on the same reference liquid, the difference between the measured results shall not be greater than the value shown by the repeatability curve in Figure 3. For two successive tests on the same sample, the difference between the measured results shall not be greater than the value shown by the repeatability curve in Figure 4.
  • 11.1.2 Reproducibility: In different laboratories, by different operators, using different instruments, the difference between two single determination results on the same reference liquid shall not be greater than the value shown by the reproducibility curve in Figure 3. For the same sample, the difference between two single determination results shall not be greater than the value shown by the reproducibility curve in Figure 4.
• 11.2 Judge the reliability of the test results using mode B according to the following provisions (95% confidence level).
  • 11.2.1 Repeatability: In the same laboratory, by the same operator, using the same instrument, two successive tests on the same reference liquid, the maximum difference between the measured results shall not be greater than 9. For two successive tests on the same sample, the maximum difference between the measured results shall not be greater than 16.
  • 11.2.2 Reproducibility: In different laboratories, by different operators, using different instruments, the maximum difference between two single determination results on the same reference liquid shall not be greater than 10. For the same sample, the maximum difference between two single determination results shall not be greater than 19.
• The specific curve values of Figure 3 and Figure 4: the source is a figure, source-text extraction no readable values are given, requires confirmation against the source standard (source-text extraction).

11. Report

• 12.1 Report the results measured in 10.16.1; for mode A operation report the MSEP-A rating result; for mode B operation report the MSEP-B rating result.
• 12.2 Take the arithmetic mean of the two results of duplicate determinations as the test result.

12. Reference Documents

• GB/T 11129 Determination of water separation index of jet fuels (see the referenced standards in Chapter 2; 4.6, 4.7 mention that the rating result is the same as GB/T 11129)
• ASTM D3948-93 "Standard Test Method for Determining Water Separation Characteristics of Aviation Turbine Fuels by Portable Water Separator" (additional note, equivalent adoption)

13. Source and verification

This page is an AI translation of the available Chinese method card. Human verification is pending. It is not an official translation of the standard. Check the source standard and product certificate before use.

14. Quick Reference for Questions and Answers