Active Standard ASTM D4768 | Developed by Subcommittee: D27.03
Book of Standards Volume: 10.03
Historical (view previous versions of standard)
Significance and Use
In new electrical insulating oil, this test method provides a quantitative measure of the amounts of 2,6-ditertiary-butyl para-cresol and 2,6-ditertiary-butyl phenol that have been added to the oil. In a used oil, the test measures the amount of these inhibitors remaining in the oil. This test method is suitable for manufacturing control, specification acceptance, and service evaluation.
This test method is used to separate, identify, and quantify the inhibitors with minimal interference and matrix effects.
This test method has also been used successfully to determine the inhibitor concentrations in other insulating liquids such as esters and high-temperature hydrocarbons.
1.1 This test method covers the determination by gas chromatography of 2,6-ditertiary-butyl para-cresol and 2,6-ditertiary-butyl phenol in new and used insulating liquids at concentrations up to 0.5 %. It includes the determination in Type I and II insulating mineral oils as specified in Specification D3487, but has also been used to measure these inhibitors in other insulating liquids, such as esters and high fire-point hydrocarbons.
1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
D923 Practices for Sampling Electrical Insulating Liquids
D3487 Specification for Mineral Insulating Oil Used in Electrical Apparatus
D5222 Specification for High Fire-Point Mineral Electrical Insulating Oils
E260 Practice for Packed Column Gas Chromatography
ICS Number Code 29.040.10 (Insulating oils)