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 111 of 460

FED-STD-791D

c. Paragraph 5.5: After removing the beaker containing the barium sulfate from the

hot plate, permit the barium sulfate to settle for a minimum of 4 hours, preferably overnight.

d. Paragraph 5.5: After the barium sulfate has settled for a minimum of 4 hours, filter

the supernatant liquid through a Whatman No. 24 or equivalent filter paper and wash with hot

water until all traces of barium chloride are removed. The active sulfur content of the cutting

fluid is equivalent to the difference between the total sulfur content of the cutting fluid (as

determined in 6.2.2) and the sulfur content of the reacted cutting fluid.

6.2.2 Total sulfur. Determine the total sulfur content of the cutting fluid in accordance

with ASTM D 129 with the exceptions listed in paragraph 6.2.1.

7. CALCULATIONS

7.1 Weight percent of sulfur as calculated in 6.1 of ASTM D 129.

7.2

Active sulfur content = Total sulfur content - sulfur content of reacted fluid

8. REPORTING

8.1 Report active and total sulfur contents to the nearest 0.01%.

9. PRECISION

9.1 Reference paragraph 8.1 of ASTM D 129 for percent sulfur contents.

9.2 No precision data available for sulfur content of reacted fluids.

Method Prepared By:

Army - AR � 1986

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