1、Designation:D609716Standard Test Method forRelative Resistance to Vented Water-Tree Growth in SolidDielectric Insulating Materials1This standard is issued under the fixed designation D6097;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revis
2、ion,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the relative resistance to ventedwater-tree growth in solid translucent thermoplast
3、ic or cross-linked electrical insulating materials.This test method isespecially applicable to extruded polymeric insulation materi-als used in medium-voltage cables.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 This st
4、andard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitation prior to use.For specific hazardstatements
5、see 8.1.1.4 There is no similar or equivalent IEC standard.2.Referenced Documents2.1 ASTM Standards:2D1711 Terminology Relating to Electrical InsulationD1898 Practice for Sampling of Plastics(Withdrawn 1998)3D1928 Practice for Preparation of Compression-MoldedPolyethylene Test Sheets and Test Specim
6、ens(Withdrawn2001)3D2275 Test Method for Voltage Endurance of Solid Electri-cal Insulating Materials Subjected to Partial Discharges(Corona)on the SurfaceD3756 Test Method for Evaluation of Resistance to Electri-cal Breakdown by Treeing in Solid Dielectric MaterialsUsing Diverging Fields3.Terminolog
7、y3.1 Definitions:3.1.1 Use Terminology D1711 for definitions of terms usedin this test method and associated with electrical insulationmaterials.3.2 Definitions of Terms Specific to This Standard:3.2.1 water tree length(WTL),nthe maximum length of astained tree-like micro-channel path in millimeters
8、,measuredfrom the tip of the conical defect in the direction of the conicalaxis.3.2.2 resistance to water-tree growth(RWTG),na dimen-sionless value which is L divided by the WTL.3.2.3 thickness of point-to-plane specimen(L),nthe ver-tical distance in millimeters from the tip of the conical defectto
9、the opposite surface of the solid dielectric material.3.2.4 semiconductive shield,npolymer/carbon black com-posite material used in medium voltage cables with volumeresistivity between 104and 105ohm-cm.4.Summary of Test Method4.1 Ten compression-molded disk specimens,each contain-ing a conical-shape
10、d defect,are subjected to an applied voltageof 5 kV at 1 kHz and 23 6 2C in an aqueous conductivesolution of 1.0 N sodium chloride(NaCl)for 30 days.Thiscontrolled conical defect is created by a sharp needle with anincluded angle of 60 and a tip radius of 3 m.The electricalstress at the defect tip is
11、 enhanced and is estimated by theMasons Hyperbolic point-to-plane stress enhancement equa-tion.4This enhanced electrical stress initiates the formation ofa vented water-tree grown from the defect tip.Each treedspecimen is stained and sliced.The water-tree length andpoint-to-plane specimen thickness
12、measured under microscopeare used to calculate a ratio that is defined as the resistance towater-tree growth.1This test method is under the jurisdiction of ASTM Committee D09 onElectrical and Electronic Insulating Materials and is the direct responsibility ofSubcommittee D09.12 on Electrical Tests.C
13、urrent edition approved Nov.1,2016.Published December 2016.Originallyapproved in 1997.Last previous edition approved in 2008 as D6097 01a(2008)1.DOI:10.1520/D6097-16.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book
14、of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4The sole source of supply of the base,Dow Corning 3110RTV,the catalyst,Dow Corning RTV Catalyst S,and the sealant,D
15、ow Corning Multipurpose SiliconeSealant 732,known to the committee at this time is Dow Corning,Inc.,Midland,MI48686.If you are aware of alternative suppliers,please provide this information toASTM International Headquarters.Your comments will receive careful consider-ation at a meeting of the respon
16、sible technical committee,which you may attend.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.Significance and Use5.1 This is a laboratory test designed to simulate the growthof vented water-trees in the solid dielectric insulating materialinitiated by a sharp protrusion at the insulating and conductiveinterface under a wet environment in a high electrical field.Water-treeing is the phenomenon which describes the appear-ance of tre