1、Designation: D876 13Standard Test Methods forNonrigid Vinyl Chloride Polymer Tubing Used for ElectricalInsulation1This standard is issued under the fixed designation D876; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of
2、 last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope*1.1 These test methods cover the t
3、esting of general-purpose(Grade A), low-temperature (Grade B), and high-temperature(Grade C)2nonrigid vinyl chloride polymer tubing, or itscopolymers with other materials, for use as electrical insula-tion. For the purpose of these test methods nonrigid tubingshall be tubing having an initial elonga
4、tion in excess of 100 %at break.NOTE 1These test methods are similar but not identical to those inIEC 606842.1.2 The values stated in inch-pound units are to be regardedas standard, except for temperature, which shall be expressedin degrees Celsius. The values given in parentheses aremathematical co
5、nversions to SI units that are provided forinformation only and are not considered standard.1.3 The procedures appear in the following sections:Procedure SectionASTM ReferenceStandardBrittleness Temperature 43 45 D746Corrosion Tests 74 85 D1000Dielectric Breakdown Voltage at High Humidity 65 73 E104
6、Dielectric Breakdown Voltage 58 64 D149Dimensional Tests 8 14 D374Effect of Elevated Temperatures 25 36 D412Flammability Test 1521Oil Resistance Test 35 42 D471Penetration Test 4651Sampling 6Strain Relief Test 6873Tension Test 22 24 D412Test Conditions 7Volume Resistivity 52 57 D2571.4 This standard
7、 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 limitations prior to use. For specific hazardstatements,
8、see Section 5.1.5 For fire test caveats, see Section 15.2. Referenced Documents2.1 ASTM Standards:3D149 Test Method for Dielectric Breakdown Voltage andDielectric Strength of Solid Electrical Insulating Materialsat Commercial Power FrequenciesD257 Test Methods for DC Resistance or Conductance ofInsu
9、lating MaterialsD374 Test Methods for Thickness of Solid Electrical Insu-lation (Withdrawn 2013)4D412 Test Methods for Vulcanized Rubber and Thermoplas-tic ElastomersTensionD471 Test Method for Rubber PropertyEffect of LiquidsD746 Test Method for Brittleness Temperature of Plasticsand Elastomers by
10、ImpactD1000 Test Methods for Pressure-Sensitive Adhesive-Coated Tapes Used for Electrical and Electronic Applica-tionsD1711 Terminology Relating to Electrical InsulationD5032 Practice for Maintaining Constant Relative Humidityby Means of Aqueous Glycerin SolutionsE104 Practice for Maintaining Consta
11、nt Relative Humidityby Means of Aqueous SolutionsE176 Terminology of Fire Standards2.2 IEC Standards:606842 Flexible insulating sleeving, Part 2, Methods oftest53. Terminology3.1 Definitions:1These test methods are under the jurisdiction of ASTM Committee D09 onElectrical and Electronic Insulating M
12、aterials and are the direct responsibility ofSubcommittee D09.07 on Flexible and Rigid Insulating Materials.Current edition approved Nov. 1, 2013. Published December 2013. Originallyapproved in 1946. Last previous edition approved in 2009 as D876 09. DOI:10.1520/D0876-13.2Test methods applicable to
13、Grade B will be specified at a later date.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.4The last approved
14、version of this historical standard is referenced onwww.astm.org.5Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harb
15、or Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.1.1 For definitions pertaining to electrical insulation, referto Terminology D1711.3.1.2 For definitions pertaining to fire standards, refer toTerminology E176.3.2 Definitions of Terms Specific to This Standard:3.2.1 brittlenes
16、s temperature, nthat temperature at which50 % of the specimens fail when the specified number aretested, using the apparatus and conditions specified.3.2.2 corrosive effect, nunder the prescribed conditions,the percentage change in electrical resistance of a fine copperwire in contact with the tubin
17、g.3.2.3 resistance to penetration, nthat property of tubingindicated by its resistance to high local pressures, as deter-mined by the temperature at which a steel ball punctures thetubing under the conditions of loading and temperature risespecified in these test methods.3.2.4 wall thickness, nan av
18、erage value determined as onehalf of the difference between the inside and outside diametersof the tubing measured by the test method prescribed herein.4. Significance and Use4.1 These test methods include most of the test methods thatare considered important to characterize nonrigid vinyl chlo-ride
19、 polymer tubing. While they were developed initially forthis type of extruded tubing, their use is not limited to this typeof tubing.4.2 Variations in these test methods or alternate contempo-rary methods are acceptable for use determine the values forthe properties in this standard provided such me
20、thods ensurequality levels and measurement accuracy equal to or better thanthose prescribed herein. It is the responsibility of the organi-zations using alternate test methods to be able to demonstratethis condition. In cases of dispute, the test methods specifiedherein shall be used.NOTE 2Provision
21、 for alternate methods is necessary because of (1) thedesire to simplify procedures for specific applications without altering theresult, and (2) the desire to eliminate redundant testing and use datagenerated during manufacturing process control, including that generatedunder Statistical Process Co
22、ntrol (SPC) conditions, using equipment andmethods other than those specified herein. An example would be the useof laser micrometers or optical comparators to measure dimensions.5. Hazards5.1 Lethal voltages are a potential hazard during theperformance of this test. It is essential that the test ap
23、paratus,and all associated equipment electrically connected to it, beproperly designed and installed for safe operation. Solidlyground all electrically conductive parts which it is possible fora person to contact during the test. Provide means for use atthe completion of any test to ground any parts
24、 which were athigh voltage during the test or have the potential for acquiringan induced charge during the test or retaining a charge evenafter disconnection of the voltage source. Thoroughly instructall operators as to the correct procedures for performing testssafely. When making high voltage test
25、s, particularly in com-pressed gas or in oil, it is possible for the energy released atbreakdown to be suffcient to result in fire, explosion, or ruptureof the test chamber. Design test equipment, test chambers, andtest specimens so as to minimize the possibility of suchoccurrences, and to eliminate
26、 the possibility of personal injury.If the potential for fire exists, have fire suppression equipmentavailable.6. Sampling6.1 Select a sufficient number of pieces of tubing in such amanner as to be representative of the shipment.6.2 Cut the number of specimens required for the purpose oftests from t
27、he pieces selected in accordance with 6.1, takingcare to select material that is free from obvious defects.7. Test Conditions7.1 Unless otherwise specified in these test methods, con-duct tests at atmospheric pressure and at a temperature of 23 62C(736 4 F). Room temperature, as stated in these test
28、methods, shall be within this temperature range.DIMENSIONAL TESTS8. Significance and Use8.1 The inside diameter and wall thickness are of impor-tance as a measure of dimensional uniformity. They alsoprovide important data for design purposes, and are used in thecalculation of certain physical and el
29、ectrical properties of thetubing.9. Apparatus9.1 Tapered-Steel GagesUse chromium-plated gages suit-able for covering the range of tubing sizes shown in Table 1.The gages shall have a uniform taper of 0.010 in./1 in. (0.010mm/mm) of length, and shall be graduated with circularlathe-cut rings every 0.
30、5 in. (13 mm) of length. The graduationsshall then represent a uniform increase in diameter of 0.005in./0.5 in. (0.010 mm/mm) of length.9.2 MicrometersUse machinists type micrometers suit-able for covering the range of tubing sizes shown in Table 1.9.3 Steel ScaleA steel scale graduated in 0.01 in.
31、(0.25mm).10. Test Specimens10.1 Cut a 1-in. (25-mm) specimen free of kinks from thesample. Perform this operation perpendicular to the longitudi-nal axis of the tubing specimen, giving a specimen 1 in. inlength having cleanly cut square ends.11. Procedure for Measuring Inside Diameter11.1 Select a g
32、age that will fit part way into the tubularspecimen. Slip the specimen, without forcing (Note 3), over thegage until there is no visible air space between the end of thespecimen and the gage anywhere on the circumference. Con-sider this point on the gage the inside diameter of the specimen.NOTE 3Whe
33、n the tubing specimen tends to stick, it is acceptable todip the gage in water to facilitate slipping the specimen over the gage.However, when water is used as a lubricant on the gage, exercise sufficientcaution to ensure that the specimen is not forced on the gage, therebystretching the specimen.D8
34、76 13211.2 Determine the diameter at the point of contact betweenthe specimen and gage by referring to the nearest visiblegraduation. With the steel scale, measure any distance betweenthe edge of the specimen and the nearest graduation. Each 0.1in. (2.5 mm) on the length of the gage represents an in
35、crease of0.001 in. (0.025 mm) in diameter. Since the diameter at thenearest graduation is known, obtain the inside diameter of thespecimen by interpolation and report to the nearest 0.001 in.12. Procedure for Measuring Outside Diameter12.1 With the specimen located on the tapered gage asdescribed in
36、 11.1, make three outside diameter measurementsapproximately 120 apart and adjacent to the edge of eachspecimen. Make the measurements in accordance with TestMethods D374 usingApparatus B, and observing the followingadditional details:12.1.1 Support the micrometer to allow both hands to befree for m
37、anipulation.12.1.2 Measure the outside diameter adjacent to, but not onor over the cut edge, and12.1.3 Rotate the tubular specimen, which is on the taperedmandrel, so that the rotation is an oscillating motion with theoutside surface of the tube just touching the fixed anvil of themicrometer. Slowly
38、 move the micrometer spindle onto thesurface of the tube until the first definite increase in theresistance to rotation of the specimen is encountered. Themicrometer reading at this time is the outside diameter of thespecimen.13. Report13.1 Report the following information:13.1.1 Inside diameter of
39、the specimen to the nearest 0.001in. (0.025 mm),13.1.2 All readings on outside diameter of the specimen tothe nearest 0.001 in.,13.1.3 Average outside diameter, and13.1.4 Average wall thickness.14. Precision and Bias14.1 The precision of this test method has not been deter-mined due to inadequate vo
40、luntary participation and fundingneeded to conduct the round-robin testing. A statement of biasis unavailable in view of the lack of a standard referencematerial for this property.FLAMMABILITY TEST15. Scope15.1 This is a fire-test-response standard. The test proceduredescribed measures the resistanc
41、e of the tubing to ignition orthe spread of flame after ignition when tested under thespecified conditions.15.2 This standard is used to measure and describe theresponse of materials, products, or assemblies to heat andflame under controlled conditions, but does not by itselfincorporate all factors
42、required for fire hazard or fire riskassessment of the materials, products, or assemblies underactual fire conditions.15.3 Fire testing is inherently hazardous. Adequate safe-guards for personnel and property shall be employed inconducting these tests.16. Significance and Use16.1 This is an acceptab
43、le test for use to compare tubingmade from different compounds provided that specimens withthe same dimensions are used, but it is not necessarily ameasure of the flammability of the compound.17. Apparatus17.1 Sheet Metal EnclosureA three-walled sheet metalenclosure 12 in. (300 mm) wide by 14 in. (3
44、60 mm) deep by 29in. (740 mm) high, open at the top. It shall be equipped withtwo parallel horizontal metal rods 16 in. (410 mm) apart, sosituated that a wire stretched perpendicularly across each rodshall be at a 70 angle with the horizontal. The lower rod shallbe approximately 2 in. (50 mm) from t
45、he rear wall.17.2 Bare Steel WireA length of bare steel wire, approxi-mately 0.029 in. (0.74 mm) in diameter, shall be used forsupporting the specimens during the test.17.3 BurnerAburner with a38-in. (9.5-mm) nominal boreand suitable for the gas supplied. The tube of the burner shallTABLE 1 Tubing S
46、izesSizeInside Diameter, in.AMax Min Nominal2 in. 2.070 2.000 134 in. 1.812 1.750 112 in. 1.550 1.500 114 in. 1.290 1.250 1 in. 1.036 1.000 78 in. 0.911 0.875 34 in. 0.786 0.750 58 in. 0.655 0.625 12 in. 0.524 0.500 716 in. 0.462 0.438 38 in. 0.399 0.375 516 in. 0.334 0.3125 No. 0 0.347 0.325 0.330N
47、o. 1 0.311 0.289 0.294No. 2 0.278 0.258 0.263No. 3 0.249 0.229 0.234No. 4 0.224 0.204 0.208No. 5 0.198 0.182 0.186No. 6 0.178 0.162 0.166No. 7 0.158 0.144 0.148No. 8 0.141 0.129 0.133No. 9 0.124 0.114 0.118No. 10 0.112 0.102 0.106No. 11 0.101 0.091 0.095No. 12 0.089 0.081 0.085No. 14 0.072 0.064 0.0
48、66No. 16 0.061 0.051 0.053No. 18 0.049 0.040 0.042No. 20 0.039 0.032 0.034ANOTEOne inch equals 25.4 mm.D876 133be approximately 312 in. (90 mm) long above the primary inlet.It shall be mounted upon a positioning mechanism similar tothat shown in Fig. 1. As shown in the figure, a pivotedpositioner wh
49、ich forms an extension of the center line of theburner barrel is attached to the barrel of the burner so as tolocate the exact point of impingement of the inner cone on thetest specimen. The base of the burner shall be tilted 25 fromthe horizontal during the period that the flame is applied to thespecimen, and the flame shall impinge upon the specimen at anangle of 45. The system shall contain a gas regulating valve aswell as a shutoff valve.17.4 Gas SupplyPublic utility or propane gas are accept-able for use. For refere
