Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
This standard is drafted in accordance with the rules given in GB/T 1.1-2009.
This standard replaces GB/T 14542-2005 Guide for maintenance and supervision of transformer oil in service, and has the following main technical changes, in addition to editorial changes, made with respect to GB/T 14542-2005:
—The standard name has been changed to Guide for maintenance and supervision of transformer oil;
—The application scope of the standard has been modified;
—The normative references have been modified;
—The terms and definitions have been introduced;
—The contents in the clause of sampling have been simplified;
—The inspection items and quality criteria for oil after new oil purification and hot oil circulation have been modified;
—The quality criteria and inspection frequency of in-service transformer oil have been modified, and items including color, gassing, charging tendency, corrosive sulfur, particulate contamination, antioxidant additive content, furfural content and DBDS content have been introduced;
—The interpretation of test results has been deleted;
—The causes for in-service transformer oil exceeding limits and actions taken have been modified, and limits, possible causes and countermeasures of corrosive sulfur, particulate contamination, furfural content and DBDS content have been introduced;
—The oil compatibility (oil mixing) has been modified;
—The contents of the clauses regarding anti-aging measures for in-service oil and oil treatment have been consolidated and modified, and the title has been changed to "Maintenance of in-service transformer oil";
—The contents of the clause regarding of oil storage, transportation and technical management have been modified;
—The informative Annex A has been deleted.
—The contents in Annex B of the original standard have been modified.
This standard was prepared using the redrafting method with reference to IEC 60422:2013 Mineral insulating oils in electrical equipment—Supervision and maintenance guidance, and is not equivalent to IEC 60422:2013.
This standard was proposed by the China Electricity Council (CEC).
This standard is under the jurisdiction of the National Technical Committee on Electrochemistry of Standardization Administration of China (SAC/TC 322).
The previous editions of this standard are as follows:
—GB/T 14542-1993, GB/T 14542-2005.
Guide for maintenance and supervision of transformer oil
1 Scope
This standard gives principles for maintenance and supervision of transformer oil.
This standard is applicable to mineral insulating oils used in oil-filled electrical equipment such as power transformers, reactors, instrument transformers, and oil-filled bushings.
This standard does not apply to synthetic insulating liquids.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 261 Determination of flash point—Pensky-Martens closed cup method
GB 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 (tanδ) and d.c. resistivity
GB/T 6540 Petroleum products—Determination of color
GB/T 6541 Petroleum products—Mineral oils—Determination of interfacial tension of oil against water—Ring method
GB/T 7595 Quality of transformer oils in service
GB/T 7597 Method of sampling for transformer and turbine oils in electric power industry
GB/T 7598 Determination of water-soluble acid in transformer oils in service
GB/T 7600 Determination of water content in transformer oils and turbine oils in service by coulometric method
GB/T 8926-2012 Standard test method for insolubles in used lubricating oils
GB 50150 Standard for hand-over test of electric equipment electric equipment installation engineering
DL/T 285 Determination of corrosive sulfur in mineral insulating oils—Insulated copper flat wire method
DL/T 385 Determination of electrification tendency of transformer oil
DL/T 419 Power oil terminology
DL/T 421 Determination of oil volume resistivity of power oil
DL/T 429.6 Open cup aging test for power oils
DL/T 429.7 Determination of sludge by precipitation
DL/T 432 Determination of particulate contamination in power oils
DL/T 596 Preventive test procedures for power equipment
DL/T 703 Determination of gas content in insulating oil by gas chromatography
DL/T 722 Guideline for the analysis and determination of dissolved gases in transformer oil
DL/T 1096 Particle size limit in transformer oil
DL/T 1355 Determination of furfural content in transformer oil—Liquid chromatography
DL/T 1419 Guideline for reclamation and use of transformer oil
DL/T 1459 Determination of the content of metal passivator in mineral insulating oils—High performance liquid chromatography
DL/T 1552 Guideline for storage management of transformer oil
NB/SH/T 0810 Determination of gassing characteristic of insulating liquid under electric field and ionization effect
NB/SH/T 0812 Determination of 2-furfural and related components in mineral insulating oil
SH/T 0802 Determination of 2,6-bi-tert-butyl-paracresol in insulating oils
IEC 60422 Mineral insulating oils in electrical equipment—Supervision and maintenance guidance
IEC 62697-1 Test methods for quantitative determination of corrosive sulfur compounds in unused and used insulating liquids—Part 1: Test method for quantitative determination of dibenzyl disulfide (DBDS)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in DL/T 419 and the following apply.
3.1
mineral insulating oil
refined insulating oil from natural petroleum
[Definition 3.9 in DL/T 419-2015]
3.2
reconditioning
process that reduces the content of impurities such as gases, water, and solid particles in used oil products to an acceptable level by physical processing
[Definition 8.2 in DL/T 419-2015]
3.3
reclaiming, regeneration
process that eliminates harmful chemical components from the oil by chemical and physical processing so as to restore the oil properties as close as possible to its original values
[Definition 8.3 in DL/T 419-2015]
4 Sampling
Sampling containers and methods are implemented in accordance with GB/T 7597, and containers and methods for measuring particle contamination in oil are implemented in accordance with DL/T 432.
5 Acceptance of new transformer oil
5.1 Acceptance of new oil
During the acceptance of new oil, all accepted oil products shall be monitored to prevent errors or introduction of contaminants. New oil shall be accepted in accordance with GB 2536, or may be accepted in accordance with relevant international standards or the contract.
5.2 Inspection of new oil before filling in transformer (reactor)
Before filling in equipment, new oil shall be filtered with vacuum filterer to remove water, gases and other particulate impurities from the oil, to the satisfaction of Table 1. Inspection of instrument transformer and bushing oil is performed in accordance with the relevant provision of GB 50150.
Table 1 Quality indicators of filtered new oil
Item Equipment voltage rating/kV
1 000 750 500 330 220 ≤110
Breakdown voltage/kV ≥75 ≥75 ≥65 ≥55 ≥45 ≥45
Moisture/(mg/L) ≤8 ≤10 ≤10 ≤10 ≤15 ≤20
Dielectric dissipation factor (DDF) (90℃) ≤0.005
Particulate contamination/particle a ≤1 000 ≤1 000 ≤2 000 — — —
Note: When necessary, filtered new oil may be inspected for the content of dissolved gas components in the oil according to DL/T 722.
a Number of particles larger than 5 μm in 100 mL of oil.
5.3 Inspection of new oil after filling in transformer (reactor) and thermal circulation
After filling in transformer (reactor) and thermal circulation, the new oil shall meet the requirements of Table 2.
Table 2 Quality indication of the oil after thermal circulation
Item Equipment voltage rating/kV
1 000 750 500 330 220 ≤110
Breakdown voltage/kV ≥75 ≥75 ≥65 ≥55 ≥45 ≥45
Moisture/(mg/L) ≤8 ≤10 ≤10 ≤10 ≤15 ≤20
Gas content in oil (by volume)/% ≤0.8 ≤1 ≤1 ≤1 — —
Dielectric dissipation factor (90 ℃) ≤0.005
Particulate contamination/particle a ≤1 000 ≤2 000 ≤3 000 — — —
a Number of particles larger than 5 μm in 100 mL of oil.
5.4 Inspection before energization for service of new equipment
The quality of oil, after filling in a qualified new transformer and thermal circulation but before energization for service, shall meet the requirements under "oil before service" in Table 3. The content of dissolved gas components in oil shall be inspected in accordance with DL/T 722.
6 Inspection of in-service transformer oil
6.1 Quality criteria and inspection frequency of in-service transformer oil
6.1.1 The quality of in-service oil for transformer and circuit breaker shall be inspected in accordance with GB/T 7595, and oils for specific equipment shall be inspected as specified by the manufacturer. The quality criteria of in-service transformer oil are shown in Table 3, and those of in service circuit breaker oil are shown in Table 4.
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Sampling
5 Acceptance of new transformer oil
6 Inspection of in-service transformer oil
7 Oil compatibility (mixed oil)
8 Maintenance of in-service transformer oil
9 Transformer sludge flushing
10 Storage and transportation of oil
11 Technical files and information of equipment
12 Safety and health
Annex A (Informative) Measures to prevent transformer oil deterioration
Annex B (Informative) Common materials for oil aging prevention and oil processing methods
Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
This standard is drafted in accordance with the rules given in GB/T 1.1-2009.
This standard replaces GB/T 14542-2005 Guide for maintenance and supervision of transformer oil in service, and has the following main technical changes, in addition to editorial changes, made with respect to GB/T 14542-2005:
—The standard name has been changed to Guide for maintenance and supervision of transformer oil;
—The application scope of the standard has been modified;
—The normative references have been modified;
—The terms and definitions have been introduced;
—The contents in the clause of sampling have been simplified;
—The inspection items and quality criteria for oil after new oil purification and hot oil circulation have been modified;
—The quality criteria and inspection frequency of in-service transformer oil have been modified, and items including color, gassing, charging tendency, corrosive sulfur, particulate contamination, antioxidant additive content, furfural content and DBDS content have been introduced;
—The interpretation of test results has been deleted;
—The causes for in-service transformer oil exceeding limits and actions taken have been modified, and limits, possible causes and countermeasures of corrosive sulfur, particulate contamination, furfural content and DBDS content have been introduced;
—The oil compatibility (oil mixing) has been modified;
—The contents of the clauses regarding anti-aging measures for in-service oil and oil treatment have been consolidated and modified, and the title has been changed to "Maintenance of in-service transformer oil";
—The contents of the clause regarding of oil storage, transportation and technical management have been modified;
—The informative Annex A has been deleted.
—The contents in Annex B of the original standard have been modified.
This standard was prepared using the redrafting method with reference to IEC 60422:2013 Mineral insulating oils in electrical equipment—Supervision and maintenance guidance, and is not equivalent to IEC 60422:2013.
This standard was proposed by the China Electricity Council (CEC).
This standard is under the jurisdiction of the National Technical Committee on Electrochemistry of Standardization Administration of China (SAC/TC 322).
The previous editions of this standard are as follows:
—GB/T 14542-1993, GB/T 14542-2005.
Guide for maintenance and supervision of transformer oil
1 Scope
This standard gives principles for maintenance and supervision of transformer oil.
This standard is applicable to mineral insulating oils used in oil-filled electrical equipment such as power transformers, reactors, instrument transformers, and oil-filled bushings.
This standard does not apply to synthetic insulating liquids.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 261 Determination of flash point—Pensky-Martens closed cup method
GB 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 (tanδ) and d.c. resistivity
GB/T 6540 Petroleum products—Determination of color
GB/T 6541 Petroleum products—Mineral oils—Determination of interfacial tension of oil against water—Ring method
GB/T 7595 Quality of transformer oils in service
GB/T 7597 Method of sampling for transformer and turbine oils in electric power industry
GB/T 7598 Determination of water-soluble acid in transformer oils in service
GB/T 7600 Determination of water content in transformer oils and turbine oils in service by coulometric method
GB/T 8926-2012 Standard test method for insolubles in used lubricating oils
GB 50150 Standard for hand-over test of electric equipment electric equipment installation engineering
DL/T 285 Determination of corrosive sulfur in mineral insulating oils—Insulated copper flat wire method
DL/T 385 Determination of electrification tendency of transformer oil
DL/T 419 Power oil terminology
DL/T 421 Determination of oil volume resistivity of power oil
DL/T 429.6 Open cup aging test for power oils
DL/T 429.7 Determination of sludge by precipitation
DL/T 432 Determination of particulate contamination in power oils
DL/T 596 Preventive test procedures for power equipment
DL/T 703 Determination of gas content in insulating oil by gas chromatography
DL/T 722 Guideline for the analysis and determination of dissolved gases in transformer oil
DL/T 1096 Particle size limit in transformer oil
DL/T 1355 Determination of furfural content in transformer oil—Liquid chromatography
DL/T 1419 Guideline for reclamation and use of transformer oil
DL/T 1459 Determination of the content of metal passivator in mineral insulating oils—High performance liquid chromatography
DL/T 1552 Guideline for storage management of transformer oil
NB/SH/T 0810 Determination of gassing characteristic of insulating liquid under electric field and ionization effect
NB/SH/T 0812 Determination of 2-furfural and related components in mineral insulating oil
SH/T 0802 Determination of 2,6-bi-tert-butyl-paracresol in insulating oils
IEC 60422 Mineral insulating oils in electrical equipment—Supervision and maintenance guidance
IEC 62697-1 Test methods for quantitative determination of corrosive sulfur compounds in unused and used insulating liquids—Part 1: Test method for quantitative determination of dibenzyl disulfide (DBDS)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in DL/T 419 and the following apply.
3.1
mineral insulating oil
refined insulating oil from natural petroleum
[Definition 3.9 in DL/T 419-2015]
3.2
reconditioning
process that reduces the content of impurities such as gases, water, and solid particles in used oil products to an acceptable level by physical processing
[Definition 8.2 in DL/T 419-2015]
3.3
reclaiming, regeneration
process that eliminates harmful chemical components from the oil by chemical and physical processing so as to restore the oil properties as close as possible to its original values
[Definition 8.3 in DL/T 419-2015]
4 Sampling
Sampling containers and methods are implemented in accordance with GB/T 7597, and containers and methods for measuring particle contamination in oil are implemented in accordance with DL/T 432.
5 Acceptance of new transformer oil
5.1 Acceptance of new oil
During the acceptance of new oil, all accepted oil products shall be monitored to prevent errors or introduction of contaminants. New oil shall be accepted in accordance with GB 2536, or may be accepted in accordance with relevant international standards or the contract.
5.2 Inspection of new oil before filling in transformer (reactor)
Before filling in equipment, new oil shall be filtered with vacuum filterer to remove water, gases and other particulate impurities from the oil, to the satisfaction of Table 1. Inspection of instrument transformer and bushing oil is performed in accordance with the relevant provision of GB 50150.
Table 1 Quality indicators of filtered new oil
Item Equipment voltage rating/kV
1 000 750 500 330 220 ≤110
Breakdown voltage/kV ≥75 ≥75 ≥65 ≥55 ≥45 ≥45
Moisture/(mg/L) ≤8 ≤10 ≤10 ≤10 ≤15 ≤20
Dielectric dissipation factor (DDF) (90℃) ≤0.005
Particulate contamination/particle a ≤1 000 ≤1 000 ≤2 000 — — —
Note: When necessary, filtered new oil may be inspected for the content of dissolved gas components in the oil according to DL/T 722.
a Number of particles larger than 5 μm in 100 mL of oil.
5.3 Inspection of new oil after filling in transformer (reactor) and thermal circulation
After filling in transformer (reactor) and thermal circulation, the new oil shall meet the requirements of Table 2.
Table 2 Quality indication of the oil after thermal circulation
Item Equipment voltage rating/kV
1 000 750 500 330 220 ≤110
Breakdown voltage/kV ≥75 ≥75 ≥65 ≥55 ≥45 ≥45
Moisture/(mg/L) ≤8 ≤10 ≤10 ≤10 ≤15 ≤20
Gas content in oil (by volume)/% ≤0.8 ≤1 ≤1 ≤1 — —
Dielectric dissipation factor (90 ℃) ≤0.005
Particulate contamination/particle a ≤1 000 ≤2 000 ≤3 000 — — —
a Number of particles larger than 5 μm in 100 mL of oil.
5.4 Inspection before energization for service of new equipment
The quality of oil, after filling in a qualified new transformer and thermal circulation but before energization for service, shall meet the requirements under "oil before service" in Table 3. The content of dissolved gas components in oil shall be inspected in accordance with DL/T 722.
6 Inspection of in-service transformer oil
6.1 Quality criteria and inspection frequency of in-service transformer oil
6.1.1 The quality of in-service oil for transformer and circuit breaker shall be inspected in accordance with GB/T 7595, and oils for specific equipment shall be inspected as specified by the manufacturer. The quality criteria of in-service transformer oil are shown in Table 3, and those of in service circuit breaker oil are shown in Table 4.
Contents of GB/T 14542-2017
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Sampling
5 Acceptance of new transformer oil
6 Inspection of in-service transformer oil
7 Oil compatibility (mixed oil)
8 Maintenance of in-service transformer oil
9 Transformer sludge flushing
10 Storage and transportation of oil
11 Technical files and information of equipment
12 Safety and health
Annex A (Informative) Measures to prevent transformer oil deterioration
Annex B (Informative) Common materials for oil aging prevention and oil processing methods
