GB/T 7595-2017Quality of transformer oils in service (English PDF)

Foreword

This Standard was drafted in accordance with the rules given in GB/T 1.1-2009.

This Standard replaces GB/T 7595-2008, Quality of Transformer Oils in Service.

Compared with GB/T 7595-2008, the major changes of this Standard are as follows.

-- the application scope of the standard is modified;

-- the normative references are modified;

-- the standard for the quality of mineral transformer oils in service is modified;

-- the standard for the quality of breaker oils in service is modified;

-- the inspection items, such as chromaticity, and relevant quality indexes and test methods are added;

-- part of test methods are modified;

-- the terms and definitions are deleted;

-- part of test items are deleted;

-- test cycles and test items are deleted;

-- informative Annex A “Maximum Viscosity of Transformer Oils at the Lowest Cold-

start Energizing Temperature” is deleted;

-- informative Annex B “Effects of Different Electrode Shapes and Operating

Methods on the Measured Values of Breakdown Voltage” is deleted;

-- informative Annex C “Anti-degradation Measures for Transformer Oils in Service” is deleted.

This Standard was proposed by China Electricity Council.

1 Application Scope

This Standard specifies the quality standard for mineral transformer oils and beaker oils in service.

This Standard applies to the quality and supervision of mineral transformer oils and

breaker oils in service, which are filled in electrical equipment.

This Standard does not apply to mineral insulating oils, which are used for cables or

condensers as impregnating compounds.

2 Normative References

The following referenced documents are indispensable for the application of this

document. For dated references, only the edition dated applies to this document. For

undated references, the latest edition of the referenced documents (including all

amendments) applies to This Standard.

GB/T 261, Determination of Flash Point – Pensky-Martens Closed Cup Method

GB/T 264, Petroleum Products – Determination of Acid Number

GB/T 507, Insulating Liquids – Determination of the Breakdown Voltage at Power Frequency

GB 2536, Fluids for Electrotechnical Applications – Unused Mineral Insulating Oils for Transformers and Switchgear

GB/T 5654, Insulating Liquids – Measurement of Relative Permittivity, Dielectric Dissipation Factor and D.C. Resistivity

GB/T 6540, Petroleum Products – Determination of Colour

GB/T 6541, Petroleum Products – Mineral Oils – Determination of Interfacial Tension of Oil against Water – Ring Method

GB/T 7598, Determination of Water-soluble Acid in Transformer and Turbine Oils in Service by Colorimetric Method

GB/T 7600, Determination of Water Content in Transformer Oils in Service by Coulometric Method

GB/T 7601, Determination of Water Content for Transformer and Turbine Oils in