ASTM D3635-01

Standard Test Method for Dissolved Copper In Electrical Insulating Oil By Atomic Absorption Spectrophotometry

SCOPE
1.1 This test method covers the determination of copper in new or used electrical insulating oil of petroleum origin by atomic absorption spectrophotometry.  
1.2 The lowest limit of detectability is primarily dependent upon the method of atomization, but also upon the energy source, the fuel and oxidant, and the degree of electrical expansion of the output signal. The lowest detectable concentration is usually considered to be equal to twice the maximum variation of the background. For flame atomization, the lower limit of detectability is generally in the order of 0.1 ppm. For non-flame atomization, the lower limit of detectability is less than 0.01 ppm.  
1.3 The values stated in acceptable metric units are to be regarded as the standard.  
1.4 This standard does not purport to address all of the safety problems, 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. See 5.4 for specific precautionary statements.

General Information

• Status: Historical
• Publication Date: 09-Apr-2001
• ICS: 29.040.10 - Insulating oils
• Technical Committee: D27 - Electrical Insulating Liquids and Gases
• Drafting Committee: D27.03 - Analytical Tests

Relations

• Replaces: ASTM D3635-90(1998) - Standard Test Method for Dissolved Copper In Electrical Insulating Oil By Atomic Absorption Spectrophotometry
• Effective Date: 10-Apr-2001
• Replaced By: ASTM D3635-01(2005) - Standard Test Method for Dissolved Copper In Electrical Insulating Oil By Atomic Absorption Spectrophotometry
• Effective Date: 01-Oct-2005
• Referred By: ASTM D117-22 - Standard Guide for Sampling, Test Methods, and Specifications for Electrical Insulating Liquids
• Effective Date: 10-Apr-2001

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:D 3635–01
Standard Test Method for
Dissolved Copper In Electrical Insulating Oil By Atomic
1
Absorption Spectrophotometry
This standard is issued under the fixed designation D 3635; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope tion spectrophotometer. Alternate procedures are provided for
instruments employing flame and non-flame atomization. Con-
1.1 This test method covers the determination of copper in
centration is determined by means of calibration curves pre-
new or used electrical insulating oil of petroleum origin by
pared from standard samples.
atomic absorption spectrophotometry.
1.2 The lowest limit of detectability is primarily dependent
4. Significance and Use
upon the method of atomization, but also upon the energy
4.1 Electrical insulating oil may contain small amounts of
source, the fuel and oxidant, and the degree of electrical
dissolved metals derived either directly from the base oil or
expansion of the output signal. The lowest detectable concen-
from contact with metals during refining or service. When
tration is usually considered to be equal to twice the maximum
copper is present, it acts as a catalyst in promoting oxidation of
variation of the background. For flame atomization, the lower
the oil. This test method is useful for research for new oils and
limit of detectability is generally in the order of 0.1 ppm or 0.1
to assess the condition of service-aged oils. Consideration
mg/kg. For non-flame atomization, the lower limit of detect-
should be given to the limits of detection outlined in the scope.
ability is less than 0.01 ppm.
1.3 The values stated in SI units are to be regarded as the
5. Apparatus
standard.
5.1 Volumetric flasks, 100-mL capacity.
1.4 This standard does not purport to address all of the
5.2 Membrane filter, 0.45 µm.
safety concerns, if any, associated with its use. It is the
5.3 Burets, 5 and 50-mL capacity.
responsibility of the user of this standard to establish appro-
5.4 Atomic Absorption Spectrophotometer—The instrument
priate safety and health practices and determine the applica-
shall have an atomizer, a spectral energy source, usually
bility of regulatory limitations prior to use. See 5.4 for specific
consisting of a copper hollow cathode lamp, a monochromator
precautionary statements.
capable of isolating the desired line of radiation, an adjustable
slit, a photomultiplier tube or other photosensitive device as a
2. Referenced Documents
light measuring and amplifying device, and a read-out mecha-
2.1 ASTM Standards:
2 nismforindicatingtheamountofabsorbedradiation.Caution:
D 1193 Specification for Reagent Water
Proper ventilation must be provided to remove toxic metal
D 3487 Specification for Mineral Insulating Oil Used in
3 vapors.
Electric Apparatus
5.4.1 Instruments employing flame atomization require a
D 5222 Guide for High Fire-Point Mineral Electrical Insu-
3 nebulizer assembly, burner head, and suitable pressure and
lating Oils
flow regulating devices to maintain constant oxidant and fuel
3. Summary of Test Method flow for the duration of the tests.
5.4.1.1 Glass Syringe, 10-mL capacity.
3.1 The test specimen of oil is filtered and diluted with an
5.4.2 Instruments employing non-flame atomization require
appropriate organic solvent and analyzed in an atomic absorp-
a suitable pressure regulating device to maintain an inert
atmosphere.
1
This test method is under the jurisdiction of ASTM Committee D27 on
5.4.2.1 Graphite Furnace with background correction.
Electrical Insulating Liquids and Gases and is the direct responsibility of Subcom-
5.4.2.2 Output Device, Printer or Strip Chart Recorder (if
mittee D27.03 on Analytical Tests.
permanent record is required).
Current edition approved April 10, 2001. Published June 2001. Originally
5.4.2.3 Pipets, 1 and 5-µL.
published as D 3635 – 77. Last previous edition D 3635 – 90 (Reapproved 1998).
2
Annual Book of ASTM Standards, Vol. 11.01.
3
Annual Book of ASTM Standards, Vol 10.03.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
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D 3635–01
NOTE 2—The new oil used to make these dilutions must be the same
6. Reagents
new oil used to make the 10 µg/mL standard. Good transfers can be
6.1 Purity of Reagents—Use reagent grade chemicals in all
effected if a 50-mL buret is used for the new oil and a 5-mL buret is used
tests. 5
for the 10µ g/mL Cu standard. Do not transfer the solutions too rapidly.
6.2 Purity of Water—Unless otherwise indicated, references
8.2.3 Shake wel
...