ASTM D6097-16
(Test Method)Standard Test Method for Relative Resistance to Vented Water-Tree Growth in Solid Dielectric Insulating Materials
Standard Test Method for Relative Resistance to Vented Water-Tree Growth in Solid Dielectric Insulating Materials
SIGNIFICANCE AND USE
5.1 This is a laboratory test designed to simulate the growth of vented water-trees in the solid dielectric insulating material initiated by a sharp protrusion at the insulating and conductive interface under a wet environment in a high electrical field. Water-treeing is the phenomenon which describes the appearance of tree-like growth in organic dielectrics under an ac field when exposed to moist environments. Two types of water-trees are formed. Bow tie trees (within the dielectric) and vented water-trees formed from conductive/insulating material interface into the insulating material. The water-trees referred to in this test method are the vented type. The insulating material is the solid dielectric organic material. The conductive material is the salt solution. This salt solution is used on both sides of the insulating material to simulate the same inner and outer semiconductive shields saturated with moisture between the insulation layer used in a medium-voltage underground power cable.
5.2 This test method provides comparative data. The degree of correlation with the performance in service has not been established.
5.3 The standard test conditions are designed to grow a sufficient water-tree length for most solid dielectric insulating materials of interest before electrical breakdown occurs. Materials with a very high resistance to water-tree growth require a longer time under test conditions (such as 180 days) or higher voltage (such as 10 or 15 kV) in order to differentiate their performance. For materials with a very low resistance to water-tree growth, electrical breakdown will occur during the 30-day testing time in most instances. A shorter testing time (such as one or ten days) is recommended to prevent electrical breakdown during testing for those low water-tree resistant materials.
5.4 Other voltages, frequencies, temperatures, aqueous solutions, and defects are able to be used to evaluate specific materials for specific applications. Tempe...
SCOPE
1.1 This test method covers the relative resistance to vented water-tree growth in solid translucent thermoplastic or cross-linked electrical insulating materials. This test method is especially applicable to extruded polymeric insulation materials used in medium-voltage cables.
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.3 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 determine the applicability of regulatory limitation prior to use. For specific hazard statements see 8.1.
1.4 There is no similar or equivalent IEC standard.
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: D6097 − 16
Standard Test Method for
Relative Resistance to Vented Water-Tree Growth in Solid
1
Dielectric Insulating Materials
This standard is issued under the fixed designation D6097; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 3. Terminology
1.1 This test method covers the relative resistance to vented 3.1 Definitions:
water-tree growth in solid translucent thermoplastic or cross- 3.1.1 Use Terminology D1711 for definitions of terms used
linked electrical insulating materials. This test method is
in this test method and associated with electrical insulation
especially applicable to extruded polymeric insulation materi- materials.
als used in medium-voltage cables.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 water tree length (WTL), n—the maximum length of a
1.2 The values stated in SI units are to be regarded as
stained tree-like micro-channel path in millimeters, measured
standard. No other units of measurement are included in this
fromthetipoftheconicaldefectinthedirectionoftheconical
standard.
axis.
1.3 This standard does not purport to address all of the
3.2.2 resistance to water-tree growth (RWTG), n—a dimen-
safety concerns, if any, associated with its use. It is the
sionless value which is L divided by the WTL.
responsibility of the user of this standard to establish appro-
3.2.3 thickness of point-to-plane specimen (L), n—the ver-
priate safety and health practices and determine the applica-
bility of regulatory limitation prior to use. For specific hazard tical distance in millimeters from the tip of the conical defect
to the opposite surface of the solid dielectric material.
statements see 8.1.
1.4 There is no similar or equivalent IEC standard.
3.2.4 semiconductive shield, n—polymer/carbonblackcom-
posite material used in medium voltage cables with volume
2. Referenced Documents 4 5
resistivity between 10 and 10 ohm-cm.
2
2.1 ASTM Standards:
D1711Terminology Relating to Electrical Insulation 4. Summary of Test Method
3
D1898Practice for Sampling of Plastics (Withdrawn 1998)
4.1 Ten compression-molded disk specimens, each contain-
D1928Practice for Preparation of Compression-Molded
ingaconical-shapeddefect,aresubjectedtoanappliedvoltage
PolyethyleneTest Sheets andTest Specimens (Withdrawn
of 5 kV at 1 kHz and 23 6 2°C in an aqueous conductive
3
2001)
solution of 1.0 N sodium chloride (NaCl) for 30 days. This
D2275Test Method for Voltage Endurance of Solid Electri-
controlled conical defect is created by a sharp needle with an
cal Insulating Materials Subjected to Partial Discharges
included angle of 60° and a tip radius of 3 µm. The electrical
(Corona) on the Surface
stress at the defect tip is enhanced and is estimated by the
D3756Test Method for Evaluation of Resistance to Electri-
Mason’s Hyperbolic point-to-plane stress enhancement equa-
cal Breakdown by Treeing in Solid Dielectric Materials 4
tion. This enhanced electrical stress initiates the formation of
Using Diverging Fields
a vented water-tree grown from the defect tip. Each treed
specimen is stained and sliced. The water-tree length and
point-to-plane specimen thickness measured under microscope
1
This test method is under the jurisdiction of ASTM Committee D09 on
are used to calculate a ratio that is defined as the resistance to
Electrical and Electronic Insulating Materials and is the direct responsibility of
water-tree growth.
Subcommittee D09.12 on Electrical Tests.
Current edition approved Nov. 1, 2016. Published December 2016. Originally
ε1
approvedin1997.Lastpreviouseditionapprovedin2008asD6097–01a(2008) .
DOI: 10.1520/D6097-16.
2 4
For referenced ASTM standards, visit the ASTM website, www.astm.org, or The sole source of supply of the base, Dow Corning 3110RTV, the catalyst,
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM DowCorningRTVCatalystS,andthesealant,DowCorningMultipurposeSilicone
Standards volume information, refer to the standard’s Document Summary page on Sealant732,knowntothecommitteeatthistimeisDowCorning,Inc.,Midland,MI
the ASTM website. 48686. If you are aware of alternative suppliers, please provide this information to
3
The last approved version of this historical standard is referenced on ASTM International Headquarters. Your comments will receive careful consider-
www.astm.org. ation at a meeting of the responsible technical committee, which you may attend.
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.
´1
Designation: D6097 − 01a (Reapproved 2008) D6097 − 16
Standard Test Method for
Relative Resistance to Vented Water-Tree Growth in Solid
1
Dielectric Insulating Materials
This standard is issued under the fixed designation D6097; 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
ε NOTE—The units statement in subsection 1.2 was corrected and the warning in old Note 2 was moved into the text of
8.2 editorially in July 2008.
1. Scope
1.1 This test method covers the relative resistance to vented water-tree growth in solid translucent thermoplastic or cross-linked
electrical insulating materials. This test method is especially applicable to extruded polymeric insulation materials used in
medium-voltage cables.
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.3 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 determine the applicability of regulatory
limitation prior to use. For specific hazard statements see 8.1.
1.4 There is no similar or equivalent IEC standard.
2. Referenced Documents
2
2.1 ASTM Standards:
D1711 Terminology Relating to Electrical Insulation
3
D1898 Practice for Sampling of Plastics (Withdrawn 1998)
3
D1928 Practice for Preparation of Compression-Molded Polyethylene Test Sheets and Test Specimens (Withdrawn 2001)
D2275 Test Method for Voltage Endurance of Solid Electrical Insulating Materials Subjected to Partial Discharges (Corona) on
the Surface
D3756 Test Method for Evaluation of Resistance to Electrical Breakdown by Treeing in Solid Dielectric Materials Using
Diverging Fields
3. Terminology
3.1 Definitions:
3.1.1 Use Terminology D1711 for definitions of terms used in this test method and associated with electrical insulation
materials.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 water tree length (WTL), n—the maximum length of a stained tree-like micro-channel path in millimetres,millimeters,
measured from the tip of the conical defect in the direction of the conical axis.
3.2.2 resistance to water-tree growth (RWTG)—(RWTG), n—a dimensionless value which is L divided by the WTL.
3.2.3 thickness of point-to-plane specimen (L), n—the vertical distance in millimetresmillimeters from the tip of the conical
defect to the opposite surface of the solid dielectric material.
3.2.4 semiconductive shield, n—polymer/carbon black composite material used in medium voltage cables with volume
4 5
resistivity between 10 and 10 ohm-cm.
1
This test method is under the jurisdiction of ASTM Committee D09 on Electrical and Electronic Insulating Materials and is the direct responsibility of Subcommittee
D09.12 on Electrical Tests.
Current edition approved May 1, 2008Nov. 1, 2016. Published July 2008December 2016. Originally approved in 1997. Last previous edition approved in 20012008 as
ε1
D6097 – 01a.D6097 – 01a (2008) . DOI: 10.1520/D6097-01AR08E01.10.1520/D6097-16.
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
The last approved version of this historical standard is referenced on www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1
---------------------- Page: 1 ----------------------
D6097 − 16
4. Summary of Test Method
4.1 Ten compression-molded disk specimens, each containing a conical-shaped defect, are subjected to an applied voltage of
5 kV at 1 kHz and 23 6 2°C in an aqueous conductive solution of 1.0 N NaCl sodium chloride (NaCl) for 30 days. This controlled
conical defect is created by a sharp needle with an included angle of 60° and a tip radius of 3 μm. The electrical stress at the defect
4
tip is enhanced and can be is estimated by the Mason’s Hyperbolic point-to-plane stress enhancement equation. This enhanced
electrical stress initiates the formation of a vented water-tree grown from the defect tip. Each treed specimen is stained and sliced.
The water-tree length and point-to-plane
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.