HFRR test procedure

Filtration

1. Beforehand, all equipment that will come in contact with the diesel sample must be rinsed thoroughly with heptane and then air dried
2. Place two 0.8 micron meter Nylon Membrane Filters in the oven at 110 °C for 10 minutes to eliminate unwanted moisture
3. After the 10 minutes weigh them individually and write it down
4. Place both filters on the mesh with the heaviest one on top, as to distinguish between them
5. Fix the long tube to the piece with the mesh with the two bolts
6. Check to see that the filters cover the mesh properly to prevent leaks
7. Fix the tube in both clamps of the stand
8. Measure 500 ml of sample fuel and pour into tube
9. Connect the vacuum pump to the (glass bottle?) and switch the pump on to start filtering
10. When finished, switch the pump off and disconnect it from the (glass bottle?)
11. Pour filtered fuel in storage container
12. Rinse tube with heptane while still assembled and vacuum suck the heptane into another (glass bottle?)
13. Take the long tube and the lower piece apart
14. Place both filters in the oven, still with the heaviest one on top, at 110 °C for 15 minutes to evaporate heptane
15. Weigh filters again and write it down

High Frequency Reciprocating Rig

Preparation of Apparatus

1. Place the plates and balls into a clean glass beaker containing toluene.
2. Leave them to soak for 8hrs and then put them in the ultrasonic cleaning bath for 10min, together with the sample holders, screws and all the hardware and utensils that come into contact with the test fluid.
3. Transfer the hardware and the test specimens into an ultrasonic bath containing acetone using CLEAN tweezer.
4. Leave the hardware and specimens in the ultrasonic bath for 10min.
5. Remove it and blow dry it.

Calibration and Correction

See ISO12156 Section 7.2.

Test Procedure

1. Only use already filtered diesel samples to test on the HFRR.
2. Greatest care should be taken to adhere strictly to cleanliness requirements. Always use clean tweezers when handling the specimens and the hardware and be sure not to scratch them.
3. Check under microscope that upper ball specimen is turned so that the next test will be done on a surface with no wear/scratch marks.
4. Turn lower disc specimen to get a clean surface for new test using a tweezer.
5. Fasten lower specimen to HFRR machine, with the nipple on the right hand side, with the two small bolts.
6. Fasten upper specimen to oscillating arm with the remaining one small bolt. Be sure that the holder is horizontal before fully securing the unit.
7. Put 2ml of diesel sample in the lower specimen reservoir using a disposable pipette.
8. Attach the sling and the 200g weight to the extended arms of the upper specimen. Ensure that the suspension string hangs freely.
9. Put silver thermometer in hole next to the nipple.
10. Open the HFRR program on the computer.
11. Click on 'New Test'.
12. Name the file in which the program will save the data from the test.
13. Click on 'Start'.
14. After the test have finished, click on 'Export test' and save the data in a suitable location on the computer.
15. Without removing the ball from the test ball holder, rinse the holder several times using toluene and then several times using acetone.
16. Ultrasonically clean the top specimen for 30s.
17. Ultrasonically clean the top specimen for 30s using acetone.
18. Allow the top specimen to air dry.
19. Attach the digital camera to the top of the microscope
20. Place the upper ball specimen under the microscope under the yellow IC10 magnification.
21. Focus the microscope on the wear scar on the ball and take a picture with the digital camera.
22. If the microscope is switched on but the light does not seem to come through, lower the the voltage on the voltage control box of the microscope.
23. Place the bottom specimen in a toluene ultrasonic bath for 30s and then in toluene.

Measuring the Wear Scar

1. After taking the photo of the wear scar take the .jpg file and open it in Paint.
2. Open the ruler file (also in Paint) and measure the wear scar.
3. See Section 9,10 of ISO12156.