ASTM C1785-17
(Test Method)Standard Test Method for Concentration of Pinhole Detections in Moisture Barriers on Metal Jacketing
Standard Test Method for Concentration of Pinhole Detections in Moisture Barriers on Metal Jacketing
SIGNIFICANCE AND USE
5.1 Corrosion on the interior surface of metal jacketing can be caused by the formation of a galvanic cell between the dissimilar metals of the pipe and jacket or by crevice or pitting corrosion.
5.2 The application of a moisture barrier to the interior surface of the metal jacketing inhibits this corrosion by interfering with the galvanic cell formation or by preventing water from contacting the interior metal surface.
5.3 Holes in the moisture barrier decrease its effectiveness in preventing corrosion. Large holes, scratches, or tears in the moisture barrier visible to the naked eye are easily discerned and are cause for rejection of the metal jacketing.
5.4 Small holes called pinholes or holidays that are not visible to the naked eye but are large enough to allow corrosion are a significant concern and should be avoided to the extent possible.
5.5 This test method is used to quantify the concentration of pinhole detections present in a moisture barrier for the purpose of quality control on metal jacketing with an applied moisture barrier.
5.6 Examples of standards which have specific requirements for the maximum allowable concentration of pinhole detections in the moisture barrier are Specifications C1729 and C1767.
SCOPE
1.1 This test method covers the determination of the concentration of pinhole detections in a moisture barrier film or coating that is applied to the interior surface of metal jacketing.
1.2 Since this method relies on the completion through the metal jacketing of an electrical circuit, this method is only applicable to jacketing that is electrically conductive and has a moisture barrier applied which is not electrically conductive.
1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
1.4 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
General Information
Relations
Buy Standard
Standards Content (Sample)
This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: C1785 − 17
Standard Test Method for
Concentration of Pinhole Detections in Moisture Barriers on
1
Metal Jacketing
This standard is issued under the fixed designation C1785; 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 E691 Practice for Conducting an Interlaboratory Study to
Determine the Precision of a Test Method
1.1 This test method covers the determination of the con-
centration of pinhole detections in a moisture barrier film or
3. Terminology
coating that is applied to the interior surface of metal jacketing.
3.1 Definitions—Definitions in Terminology C168 apply to
1.2 Since this method relies on the completion through the
terms used in this specification.
metal jacketing of an electrical circuit, this method is only
3.2 Definitions of Terms Specific to This Standard:
applicable to jacketing that is electrically conductive and has a
3.2.1 continuous pinhole detection—while the test is being
moisture barrier applied which is not electrically conductive.
conducted, a continuous sounding of the audible test equip-
1.3 The values stated in inch-pound units are to be regarded
ment alarm over an area larger than the contact area of the
as standard. The values given in parentheses are mathematical
cellulose sponge.
conversions to SI units that are provided for information only
3.2.1.1 Discussion—In some cases, large portions of one or
and are not considered standard.
more of the test areas (see 8.2.1) or even all of one or more test
1.4 This standard does not purport to address all of the
areas will yield a continuous pinhole detection.This concept of
safety concerns, if any, associated with its use. It is the
a continuous pinhole detection and the area yielding this
responsibility of the user of this standard to establish appro-
performance is necessary to quantify the number of pinhole
priate safety, health, and environmental practices and deter-
detections in a sample exhibiting this phenomenon (see 9.2 and
mine the applicability of regulatory limitations prior to use.
9.3)
1.5 This international standard was developed in accor-
3.2.2 moisture barrier (moisture retarder)—a layer of plas-
dance with internationally recognized principles on standard-
tic film or other material applied to the inner side of metal
ization established in the Decision on Principles for the
jacketing to inhibit jacket corrosion by interfering with the
Development of International Standards, Guides and Recom-
formation of a galvanic cell between the dissimilar metals of
mendations issued by the World Trade Organization Technical
the pipe and jacket or by preventing crevice or pitting
Barriers to Trade (TBT) Committee.
corrosion.
2. Referenced Documents
3.2.3 pinhole—a hole completely through a moisture barrier
2
typically too small to be seen by the eye.
2.1 ASTM Standards:
C168 Terminology Relating to Thermal Insulation 3.2.4 pinhole detection—a single sounding of the audible
C1729 Specification for Aluminum Jacketing for Insulation test equipment alarm while the test is being conducted.
C1767 Specification for Stainless Steel Jacketing for Insula- 3.2.4.1 Discussion—Because pinholes are very small and
tion the dampened cellulose sponge contacts the moisture barrier in
E177 Practice for Use of the Terms Precision and Bias in an area larger than a single pinhole (see 6.4), it is theoretically
ASTM Test Methods possible that multiple pinholes in close proximity to each other
would register as a single detection. For this reason, this test
methodmeasurestheconcentrationofpinholedetectionsrather
1
ThistestmethodisunderthejurisdictionofASTMCommitteeC16onThermal
than pinholes.
Insulation and is the direct responsibility of Subcommittee C16.33 on Insulation
Finishes and Moisture.
3.2.5 holiday—synonymous with pinhole.
Current edition approved Sept. 1, 2017. Published October 2017. Originally
approved in 2013. Last previous edition approved in 2016 as C1785 – 16a. DOI:
4. Summary of Test Method
10.1520/C1785-17.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
4.1 A voltage is applied across the nonconductive moisture
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
barrier on metal jacketing using an electrode consisting of a
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. cellulose sponge dampened with an electrically conductive
Copyright © ASTM International,
...
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: C1785 − 16a C1785 − 17
Standard Test Method for
Concentration of Pinhole Detections in Moisture Barriers on
1
Metal Jacketing
This standard is issued under the fixed designation C1785; 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 covers the determination of the concentration of pinhole detections in a moisture barrier film or coating
that is applied to the interior surface of metal jacketing.
1.2 Since this method relies on the completion through the metal jacketing of an electrical circuit, this method is only applicable
to jacketing that is electrically conductive and has a moisture barrier applied which is not electrically conductive.
1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information only and are not considered standard.
1.4 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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2
2.1 ASTM Standards:
C168 Terminology Relating to Thermal Insulation
C1729 Specification for Aluminum Jacketing for Insulation
C1767 Specification for Stainless Steel Jacketing for Insulation
E177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
3. Terminology
3.1 Definitions—Definitions in Terminology C168 apply to terms used in this specification.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 continuous pinhole detection—while the test is being conducted, a continuous sounding of the audible test equipment
alarm over an area larger than the contact area of the cellulose sponge.
1
This test method is under the jurisdiction of ASTM Committee C16 on Thermal Insulation and is the direct responsibility of Subcommittee C16.33 on Insulation Finishes
and Moisture.
Current edition approved Sept. 1, 2016Sept. 1, 2017. Published September 2016October 2017. Originally approved in 2013. Last previous edition approved in 2016 as
C1785 – 16.C1785 – 16a. DOI: 10.1520/C1785-16A.10.1520/C1785-17.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3.2.1.1 Discussion—
In some cases, large portions of one or more of the test areas (see 8.2.1) or even all of one or more test areas will yield a continuous
pinhole detection. This concept of a continuous pinhole detection and the area yielding this performance is necessary to quantify
the number of pinhole detections in a sample exhibiting this phenomenon (see 9.2 and 9.3)
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1
---------------------- Page: 1 ----------------------
C1785 − 17
3.2.2 moisture barrier (moisture retarder)—a layer of plastic film or other material applied to the inner side of metal jacketing
to inhibit jacket corrosion by interfering with the formation of a galvanic cell between the dissimilar metals of the pipe and jacket
or by preventing crevice or pitting corrosion.
3.2.3 pinhole—a hole completely through a moisture barrier typically too small to be seen by the eye.
3.2.4 pinhole detection—a single sounding of the audible test equipment alarm while the test is being conducted.
3.2.4.1 Discussion—
Because pinholes are very small and the dampened cellulose sponge contacts the moisture barrier in an area larger than a single
pinhole (see 6.4), it is theoretically possible that multiple pinholes in close proximity to each other would register as a sing
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.