FED-STD-791 Lubricants, Liquid Fuels, And Related Products, Testing Method OfThis test method standard is composed of standard test methods for sampling, inspecting and testing lubricants, liquid fuels and related products. It is issued pursuant to the Federal Property and Administration Services Act of 1949, as amended and its application to the purchase of commodities referred to herein is mandatory on all Federal agencies.

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'�NOTE:This draft dated 15 April 2006' by DasH - Page 119 of 460

FED-STD-791D

b. Mount the tubes opposite each other in the centrifuge, being careful to locate the tubes

to achieve proper balance of the centrifuge.

c. Turn on the centrifuge, and increase the speed until the relative centrifugal force at the

tips of the tubes is 600 to 700. Run the centrifuge for 10 min.

d. After the ten-minute period, record the amount of sediment in each tube to the nearest

0.001 mL.

e. Repeat the 10 min centrifuging and sediment readings until the amount of sediment

remains constant for three consecutive readings.

7. CALCULATIONS

7.1 Compute the average sediment volume to the nearest 0.001 mL of each tube pair.

8. REPORTING

8.1 Report the average volume of sediment in each pair of centrifuge tubes.

9. PRECISION

9.1 Precision data have not been developed for this method.

Method prepared by:

Air Force - AFWAL/POSL - 1986

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