ASTM D7150-13

Standard Test Method for the Determination of Gassing Characteristics of Insulating Liquids Under Thermal Stress

SIGNIFICANCE AND USE
5.1 Generation of combustible gases is used to determine the condition of oil-filled electrical apparatus. Many years of empirical evidence has yielded guidelines such as those given in IEEE C57.104, IEC 60599 and IEC 61464. Industry experience has shown that electric and thermal faults in oil-filled electrical apparatus are the usual sources that generate gases. Experience has shown that some of the gases could form in the oil due to thermal stress or as a result of contamination, without any other influences.  
5.2 Some transformer oils subjected to thermal stress and oils that contain certain types of contamination may produce specific gases at lower temperatures than normally expected for their generation and hence, falsely indicate abnormal operation of the electrical apparatus. Some new oils have produced large amounts of gases, especially hydrogen, without the influence of other electrical apparatus materials or electrical stresses. This renders interpretation of the dissolved gas analysis more complicated.  
5.3 Heating for 164 h has been found to be sufficient to reach a stable and characteristic gassing pattern.  
5.4 This method uses both dry air and dry nitrogen as the sparging gas. This is to reflect either an electrical apparatus preservation system that allows oxygen to contact the oil or one that is sealed from the outside atmosphere. Oils sparged with air generally produce much more hydrogen as a percentage of the total combustible gas content as compared to oils sparged with nitrogen as these produce more hydrocarbons in relation to hydrogen.
SCOPE
1.1 This test method describes the procedures to determine the gassing characteristics due to thermal stress at 120°C of insulating liquids specifically and without the influence of other electrical apparatus materials or electrical stresses. This test method was primarily designed for insulating mineral oil. It can be applied to other insulating liquids in which dissolved gas-in-oil analysis (Test Method D3612) is commonly performed.  
1.2 This test method is particularly suited for detection of the phenomenon sometimes known as “stray gassing” and is also referred to in CIGRE TF11 B39.  
1.3 This test method is performed on transformer insulating liquids to determine the propensity of the oil to produce certain gases such as hydrogen and hydrocarbons at low temperatures.  
1.4 This test method details two procedures:  
1.5 Method A describes the procedure for determining the gassing characteristics of insulating liquids, at 120°C for 164 h.  
1.6 Method B describes the procedure for processing the insulating liquid through an attapulgite clay column to remove organic contaminants and other reactive groups that may influence the gassing behavior of an insulating liquid, which is suspected of being contaminated. This procedure applies to both new and used insulating liquids.  
1.7 The values stated in SI units are to be regarded as standard. English units are used when there is no metric equivalent.  
1.8 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 to determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 30-Nov-2013
• ICS: 29.040.01 - Insulating fluids in general
• Technical Committee: D27 - Electrical Insulating Liquids and Gases
• Drafting Committee: D27.03 - Analytical Tests

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D7150 − 13
Standard Test Method for the
Determination of Gassing Characteristics of Insulating
1
Liquids Under Thermal Stress
This standard is issued under the fixed designation D7150; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2. Referenced Documents
2
2.1 ASTM Standards:
1.1 This test method describes the procedures to determine
D1933 Specification for Nitrogen Gas as an Electrical Insu-
the gassing characteristics due to thermal stress at 120°C of
lating Material
insulating liquids specifically and without the influence of
D3612 Test Method for Analysis of Gases Dissolved in
other electrical apparatus materials or electrical stresses. This
Electrical Insulating Oil by Gas Chromatography
test method was primarily designed for insulating mineral oil.
3
2.2 IEEE Document:
It can be applied to other insulating liquids in which dissolved
C 57.104 IEEE Guide for the Interpretation of Gases Gen-
gas-in-oil analysis (Test Method D3612) is commonly per-
erated in Oil-Immersed Transformers, 2008
formed.
4
2.3 IEC Documents:
1.2 This test method is particularly suited for detection of
IEC 60599 Mineral oil-impregnated electrical equipment in
the phenomenon sometimes known as “stray gassing” and is
service – Guide to the interpretation of dissolved and free
also referred to in CIGRE TF11 B39.
gases analysis, 2007
1.3 This test method is performed on transformer insulating IEC 61464 Guide for the interpretation of dissolved gas
liquids to determine the propensity of the oil to produce certain
analysis (DGA) in bushings where oil is the impregnating
gases such as hydrogen and hydrocarbons at low temperatures. medium of the main insulation (generally paper), 1998
CIGRE TF11 B39 Gas formation tendency test for mineral
1.4 This test method details two procedures:
transformer oils, 2002
1.5 Method A describes the procedure for determining the
3. Terminology
gassingcharacteristicsofinsulatingliquids,at120°Cfor164h.
3.1 Definitions:
1.6 Method B describes the procedure for processing the
3.1.1 stray gassing, n—the production of gases in an insu-
insulating liquid through an attapulgite clay column to remove
lating liquid due to heating, contamination or in combination.
organic contaminants and other reactive groups that may
influence the gassing behavior of an insulating liquid, which is 3.1.2 Fuller’s Earth, n—highly adsorbent clay-like sub-
suspected of being contaminated. This procedure applies to
stance consisting mainly of hydrated aluminum silicates with
both new and used insulating liquids. the main minerals being montmorillonite, kaolinite, attapulgite
and palygorskite.
1.7 The values stated in SI units are to be regarded as
standard. English units are used when there is no metric
4. Summary of Test Method
equivalent.
4.1 Method A—Insulating liquid is filtered through a mixed
1.8 This standard does not purport to address all of the
cellulose ester filter. A portion of the test specimen is sparged
safety concerns, if any, associated with its use. It is the
for 30 min with dry air. A test specimen is then placed into a
responsibility of the user of this standard to establish appro-
glasssyringe,cappedandagedat120 62°Cfor164h.Thetest
priate safety and health practices and to determine the
is run in duplicate. The other portion of the test specimen is
applicability of regulatory limitations prior to use.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
1
This test method is under the jurisdiction of ASTM Committee D27 on Standards volume information, refer to the standard’s Document Summary page on
Electrical Insulating Liquids and Gases and is the direct responsibility of Subcom- the ASTM website.
3
mittee D27.03 on Analytical Tests. Available from the Institute of Electrical and Electronic Engineers, Inc, (IEEE),
Current edition approved Dec. 1, 2013. Published January 2014. Originally 445 Hoes Lane, Piscataway, NJ 08854; www.ieee.org
4
approved in 2005. Last previous edition approved in 2005 as D7150-05. DOI: Available from the International Electrotechnical Commission, 3, rue de
10.1520/D7150-13. Varembé, P.O. Box 131 CH-1211, Geneva 20, Switzerland; www.iec.ch
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D7150 − 13
sparged for 30 min with dry nitrogen. A test specimen is then 6.5 Ovens, forced-draft, adjustable to 120 6 2°C and a
placed into a glass syringe, c
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D7150 − 05 D7150 − 13
Standard Test Method for the
Determination of Gassing Characteristics of Insulating
1
Liquids Under Thermal Stress at Low Temperature
This standard is issued under the fixed designation D7150; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method describes the procedures to determine the low temperature (120°C) gassing characteristics gassing
characteristics due to thermal stress at 120°C of insulating liquids specifically and without the influence of other electrical
apparatus materials or electrical stresses. This test method was primarily designed for insulating mineral oil. It can be applied to
other insulating liquids in which dissolved gas-in-oil analysis (Test Method D3612) is commonly performed.
1.2 This test method is particularly suited for detection of the phenomenon sometimes known as “stray gassing” and is also
referred to in CIGRE TF11 B39.
1.3 This test method is performed on transformer insulating liquids to determine the propensity of the oil to produce certain
gases such as hydrogen and hydrocarbons at low temperatures.
1.4 This test method details two procedures:
1.5 Method A describes the procedure for determining the gassing characteristics of a new, unused insulating liquid, as received,
insulating liquids, at 120°C for 164 h.
1.6 Method B describes the procedure for processing the insulating liquid through an attapulgite clay column to remove organic
contaminants and other reactive groups that may influence the gassing behavior of an insulating liquid, which is suspected of being
contaminated. This procedure applies to both new and used insulating liquids.
1.7 The values stated in SI units are to be regarded as standard. English units are used when there is no metric equivalent.
1.8 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 to determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2
2.1 ASTM Standards:
D1933 Specification for Nitrogen Gas as an Electrical Insulating Material
D3612 Test Method for Analysis of Gases Dissolved in Electrical Insulating Oil by Gas Chromatography
3
D3613 Practice for Sampling Insulating Liquids for Gas Analysis and Determination of Water Content (Withdrawn 2007)
3
2.2 IEEE Document:
C 57.104 IEEE Guide for the Interpretation of Gases Generated in Oil-Immersed Transformers, 19912008
4
2.3 IEC Documents:
IEC 60599 Mineral oil-impregnated electrical equipment in service – Guide to the interpretation of dissolved and free gases
analysis, 19992007
IEC 61464 Guide for the interpretation of dissolved gas analysis (DGA) in bushings where oil is the impregnating medium of
the main insulation (generally paper), 1998
CIGRE TF11 B39 Gas formation tendency test for mineral transformer oils, 2002.2002
1
This test method is under the jurisdiction of ASTM Committee D27 on Electrical Insulating Liquids and Gases and is the direct responsibility of Subcommittee D27.03
on Analytical Tests.
Current edition approved May 1, 2005Dec. 1, 2013. Published June 2005January 2014. Originally approved in 2005. Last previous edition approved in 2005 as D7150-05.
DOI: 10.1520/D7150-05.10.1520/D7150-13.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3
Available from the Institute of Electrical and Electronic Engineers, Inc, (IEEE), 445 Hoes Lane, Piscataway, NJ 08854; www.ieee.org
4
Available from the International Electrotechnical Commission, 3, rue de Varembé, P.O. Box 131 CH-1211, Geneva 20, Switzerland; www.iec.ch
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D7150 − 13
3. Terminology
3.1 Definitions:
3.1.1 stray gassing, n—the production of gases in an insulating liquid due to heating, contamination or in combination.
3.1.2 attapulgite clay,Fuller’s Earth, n—also termed Fullers Earth. Highly highly adsorbent clay-like sub
...