ASTM C536-83(2004)e1

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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e1
Designation:C536–83(Reapproved2004)
Standard Test Method for
Continuity of Coatings in Glassed Steel Equipment by
Electrical Testing
This standard is issued under the fixed designation C 536; 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.
e NOTE—Keywords were added editorially in September 2004.
1. Scope voltage is set at 5000 V in order to show existing discontinui-
ties without breaking through the existing glass coating. A
1.1 This test method covers the detection of discontinuities
built-in current limiting device ensures electrical safety for the
in the glass coating of glassed steel equipment where such
operator.
discontinuities would result in early failure due to the attack of
the chemical contents of the vessel on the metal substrate. It is
4. Significance and Use
applicableto(1)provideamanufacturingandinspectiontestof
4.1 This test method is designed to detect existing discon-
glassed-steel equipment designed for relatively mild, low-
tinuities in the glass coating of glassed steel equipment while
temperature corrosive service, and (2) the field testing of
maintaining a voltage low enough as to be unlikely to cause
similar equipment used in more severely corrosive environ-
breakdown of the coating. The test is adaptable for manufac-
ment.
turing inspection in the processing of equipment and for field
NOTE 1—Amanufacturing test method for the latter type of equipment
use to find existing defects which can be “plugged” or repaired
is described in Test Method C 537.
before serious damage is done to the equipment.As a means of
1.2 This standard does not purport to address all of the
positive detection, it is applicable to process studies, quality
safety concerns, if any, associated with its use. It is the
control, or specification.
responsibility of the user of this standard to establish appro-
5. Definition
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use. 5.1 glassed steel (glass-lined steel or glass-coated steel)—
designations generally applied to a class of porcelain enamels
2. Referenced Document
that have high resistance to chemical attack at elevated
2.1 ASTM Standards:
temperatures and pressures.
C 537 Test Method for Reliability of Glass Coatings on
6. Interferences
Glassed Steel Reaction Equipment by High Voltage
6.1 Sincethetestmethodiselectrical,itisnecessarytohave
3. Summary of Test Method
a good ground connection between the instrument and the
3.1 The test method consists essentially of grounding the
metal substrate of the equipment being tested. It is also
metalstructureoftheequipmentbeingtestedtothegroundside
necessary that the surfaces of the glass be reasonably clean and
of a voltage generator and sweeping the surface of the glass
dry.Awet surface will conduct enough voltage to any exposed
with a suitable probe electrically connected to the other side of
metal to give an indication of a “contact” over a large area
the generator. Wherever a discontinuity exists, a discharge will
insteadofataspecificareaofdiscontinuity.Suchacapacitance
give a positive indication that such a discontinuity exists. The
discharge can be distinguished from a true failure by extending
over a large area instead of at local spots that could be
identified and marked for repair.
ThistestmethodisunderthejurisdictionofASTMCommitteeB08onMetallic
and Inorganic Coatings and is the direct responsibility of Subcommittee B08.12 on
7. Apparatus
Materials for Porcelain Enamel and Ceramic-Metal Systems.
7.1 The test apparatus comprises a voltage stabilizing trans-
Current edition approved Aug. 1, 2004. Published September 2004. Originally
approved in 1964. Last previous edition approved in 1998 as C 536 – 83 (1998).
former, a step-up transformer, a current-limiting resistance, a
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Standards volume information, refer to the standard’s Document Summary page on When requesting information, specific ref
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