Standard Specification for Natural (Vegetable Oil) Ester Fluids Used in Electrical Apparatus

Data records

• The 2026 edition of ASTM D6871 was approved on 2026-06-01 and published in July 2026. Value: 2026. Source: ASTM D6871-26, clause Front matter. Verified 2026-10-24. Record std.astm-d6871.approved
• ASTM D6871-26 is the designation of the ASTM International specification for natural (vegetable oil) ester insulating fluids, the 2026 edition of ASTM D6871. Value: ASTM D6871-26. Source: ASTM D6871-26, clause Front matter. Verified 2026-10-24. Record std.astm-d6871.designation
• ASTM D6871-26 replaces ASTM D6871-17. The front matter records that the standard was withdrawn in January 2026 and reinstated in July 2026, the month in which the 2026 edition was published. Value: 2026. Source: ASTM D6871-26, clause Front matter. Verified 2026-10-24. Record std.astm-d6871.revision-of
• ASTM D6871-26 covers insulating fluids of the natural ester class, derived from vegetable oils and of the high fire point kind, for power and distribution apparatus whether new or already in service. Source: ASTM D6871-26, clause 1.1. Verified 2026-10-24. Record std.astm-d6871.scope
• Clause 1.3 of ASTM D6871-26 notes that a natural ester fluid may not be miscible with some synthetic ester fluids and refers the question of miscibility to the fluid manufacturer. Source: ASTM D6871-26, clause 1.3. Verified 2026-10-24. Record std.astm-d6871.scope.miscibility
• The requirements of ASTM D6871-26 apply only to new fluid in its as-received condition, before any processing; the specification sets no limits for fluid that is already in service. Source: ASTM D6871-26, clause 1.4. Verified 2026-10-24. Record std.astm-d6871.scope.new-fluid-only
• ASTM D6871-26 is the responsibility of ASTM Committee D27 and its Subcommittee D27.02. Source: ASTM D6871-26, clause Front matter. Verified 2026-10-24. Record std.astm-d6871.sponsor
• Appendix X2 of ASTM D6871-26 contrasts a natural ester with a mineral oil: the interfacial tension of new ester typically reads lower, the dissipation factor and the neutralization number typically read higher, and the water saturation level of an ester is far above that of a mineral oil, so water content in an ester is better judged as a fraction of saturation than as an absolute concentration. Source: ASTM D6871-26, clause X2.1.2, X2.2.1, X2.3.1, X2.3.2. Verified 2026-10-24. Record std.astm-d6871.structure.appendix-x2.mineral-oil-comparison
• Appendix X2 of ASTM D6871-26, a nonmandatory discussion of the significance of the specified properties, records that the specification establishes no interfacial tension requirement and no oxidation stability requirement for natural ester fluid, and that the oxidation inhibitor content varies by manufacturer, who is also the source for the method of determining it. Source: ASTM D6871-26, clause X2.1.2, X2.3.3, X2.3.4. Verified 2026-10-24. Record std.astm-d6871.structure.appendix-x2.no-requirements
• Table 1 of ASTM D6871-26 addresses the chemical properties of the as-received fluid: gassing tendency by ASTM D2300, corrosive sulfur by ASTM D1275, neutralization number (total acid number) by ASTM D974, PCB content by ASTM D4059, and water content by ASTM D1533. Source: ASTM D6871-26, clause Table 1. Verified 2026-10-24. Record std.astm-d6871.structure.chemical-properties
• Table 1 of ASTM D6871-26 addresses the dielectric properties of the as-received fluid: power-frequency dielectric breakdown with disk electrodes by ASTM D877/D877M and with VDE electrodes at two gap spacings by ASTM D1816, impulse breakdown across a needle-to-sphere gap by ASTM D3300, and dissipation factor at two temperatures by ASTM D924. Source: ASTM D6871-26, clause Table 1. Verified 2026-10-24. Record std.astm-d6871.structure.dielectric-properties
• Table 1 of ASTM D6871-26 addresses the physical properties of the as-received fluid: color by ASTM D1500, fire point and flash point by ASTM D92, pour point by ASTM D97, relative density by ASTM D1298, viscosity at three temperatures by ASTM D445 or ASTM D88/D88M, and visual examination by ASTM D1524. Source: ASTM D6871-26, clause Table 1. Verified 2026-10-24. Record std.astm-d6871.structure.physical-properties
• Clause 4.1 of ASTM D6871-26 directs sampling by ASTM D923, clause 4.2 assigns each property the test method named in Table 1, and clause 5.1 requires the as-received fluid to meet every requirement of Table 1. Source: ASTM D6871-26, clause 4.1, 4.2, 5.1. Verified 2026-10-24. Record std.astm-d6871.structure.sampling-and-conformance
• Footnote A to Table 1 of ASTM D6871-26 qualifies the water determination by ASTM D1533: some natural ester formulations call for the alternate reagents of ASTM D1533 Annex A1, and when the additive package of the fluid is not known the reagents intended for aldehydes and ketones are the ones to use, since the standard reagents can otherwise give a high and erratic water result. Source: ASTM D6871-26, clause Table 1, footnote A. Verified 2026-10-24. Record std.astm-d6871.structure.water-reagents
• The licensed copy gives the full title of ASTM D6871-26 as Standard Specification for Natural (Vegetable Oil) Ester Fluids Used in Electrical Apparatus. Value: Standard Specification for Natural (Vegetable Oil) Ester Fluids Used in Electrical Apparatus. Source: ASTM D6871-26, clause Front matter. Verified 2026-10-24. Record std.astm-d6871.title