1、Designation: E 574 06Standard Specification forDuplex, Base Metal Thermocouple Wire With Glass Fiber orSilica Fiber Insulation1This standard is issued under the fixed designation E 574; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisio
2、n, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification sets forth the requirements for duplex,types E, J, K, N and T thermocouple wire, in
3、sulated withE-glass, S-glass, amorphous silica fiber or polycrystalline fiber.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 This standard does not purport to address all of thesafety problems, if any, associated with
4、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.2. Referenced Documents2.1 ASTM Standards:2D 1125 Test Methods for Electrical Conductivity and Re-sistivity of W
5、aterE 207 Test Method for Thermal EMF Test of Single Ther-moelement Materials by Comparison with a ReferenceThermoelement of Similar EMF-Temperature PropertiesE 220 Test Method for Calibration of Thermocouples ByComparison TechniquesE 230 Specification and Temperature-Electromotive Force(EMF) Tables
6、 for Standardized ThermocouplesE 344 Terminology Relating to Thermometry and Hydrom-etry3. Terminology3.1 DefinitionsThe definitions given in TerminologyE 344 shall apply to this standard.3.2 Definitions of Terms Specific to This Standard:3.2.1 amorphous silica fiber, ncontinuous filament of heatins
7、ulating material whose principal constituent is amorphoussilica.3.2.2 duplex wire, nmatched pair of parallel, solid ther-moelements, individually insulated (double wrap or braid) withinsulating fibers and a fiber braid of the same material overall.3.2.3 E-glass, nfamily of calcia-alumina-silicate gl
8、assesthat are used for general purposes and most electrical applica-tions.3.2.4 impregnate, vto saturate the fiber insulation of wireswith a high-temperature electrical insulating compound to forma moisture barrier around the wires and to inhibit fraying of thefibers.3.2.5 polycrystalline fiber, nco
9、ntinuous polycrystallinefilament of heat insulating material whose composition isalumina, boria, and silica in an approximate ratio of 3:1:2,respectively.3.2.6 S-glass, nfamily of magnesia-alumina-silicateglasses with a higher tensile strength and higher softeningtemperature than E-glass.4. Signific
10、ance and Use4.1 This specification presents the requirements for impreg-nated and non-impregnated fiber insulated thermocouple wirefor normally accepted industrial use, but does not attempt todefine such usage.4.2 A supplement contains the requirements for insulatedthermocouple wire that will be exp
11、osed to high humidity. Thepurchase order or inquiry shall specify if this supplement isrequired.5. Classification5.1 Class ADuplexE-glass fiber insulated, impregnatedwith a high-temperature electrical insulating compound andcolor coded in accordance with Specification E 230.5.2 Class BDuplexE-glass
12、fiber insulated (Note 1) notimpregnated and not color coded.5.3 Class CDuplexAmorphous silica fiber insulated(Note 2) not impregnated and not color coded.5.4 Class DDuplexPolycrystalline fiber insulated (Notes2 and 3) not impregnated and not color coded.1This specification is under the jurisdiction
13、of ASTM Committee E20 onTemperature Measurement and is the direct responsibility of Subcommittee E20.04on Thermocouples.Current edition approved May 1, 2006. Published May 2006. Originallyapproved in 1976. Last previous edition approved in 2000 as E 574 00.2For referenced ASTM standards, visit the A
14、STM 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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, Uni
15、ted States.5.5 Class EDuplexS-glass fiber insulated, impregnatedwith a high-temperature electrical insulating compound andcolor coded in accordance with Specification E 230.5.6 Class FDuplexS-glass fiber insulated (Note 1) notimpregnated and not color coded.NOTE 1May be heat treated to retard frayin
16、g when specified inordering information (6.1.8).NOTE 2Fibers may be pre-treated with an organic compound tofacilitate braiding.NOTE 3May be heat cleaned after braiding to remove organiccompound when specified in ordering information (6.1.8).6. Ordering Information6.1 The purchase order shall specify
17、 the following informa-tion:6.1.1 Total insulated wire length,6.1.2 Thermocouple type,6.1.3 Tolerance on initial values of emf versus temperature(standard or special),6.1.4 Class of insulation (see Section 5),6.1.5 Thermoelement diameter (see 7.1.2),6.1.6 Minimum acceptable continuous length per spo
18、ol, ifapplicable,6.1.7 Supplementary testing, if required (see SupplementaryRequirements),6.1.8 Special requirements (if any),6.1.9 Deviations or special requirements not covered herein,and6.1.10 Required documentation (see Section 9).7. Technical Requirements7.1 Insulated Thermocouple Wire:7.1.1 Ma
19、terialsThermoelements shall be solid thermo-couple grade materials with a smooth, bright finish (Note 4)and shall be fully annealed prior to insulating.NOTE 4An optional copper-flash coating on the iron thermoelement ispermitted to prevent rusting. This coating must be applied uniformly soinhomogeni
20、ety is not introduced.7.1.2 SizesThermoelements shall be specified in Ameri-can Wire Gage (AWG) nomenclature. Corresponding thermo-element diameters shall be as listed in Table 1.7.1.3 Calibration:7.1.3.1 Standard MethodWhen required by the purchaseorder, calibration of the insulated thermocouple wi
21、re shall beperformed by one of the procedures described in Test MethodsE 207 or E 220.7.1.3.2 Thermoelement Initial Calibration TolerancesStandard and special tolerances on initial values of emf versustemperature are given in Table 1 of Specification E 230. Thepurchase order shall specify whether st
22、andard or specialtolerances are required.7.2 Insulation Materials:7.2.1 Individual thermoelements shall be covered with abraid, or double wrap (one wrap in each direction) of glassfibers (Classes A and E), a braid of glass fibers (Classes B andF), or braid of fibers (Classes C and D).7.2.2 The outer
23、 covering shall consist of a braid of the samematerial applied over the bare thermoelements.7.2.3 For Classes A and E duplex thermoelements, theinsulation on the individual thermoelements and the outer braidshall be impregnated with a moisture and heat-resistant elec-trical insulating compound. The
24、fibers shall be bonded suffi-ciently to each other to prevent fraying under normal condi-tions of installation and service.7.2.4 Each individual Class A and E thermoelement wrap orbraid and the outer braid shall be color coded in accordancewith Specification E 230.7.2.5 The purchase order may specif
25、y that an enamelcoating be applied to each bare thermoelement designated asClass A and Class E.7.2.6 Classes B, C, D and F insulated thermoelements aresupplied without impregnation, color coding, or enamel (Notes1-4).7.2.7 Insulating materials shall be suitable for continuoususe to the temperatures
26、listed in Table 2.7.2.8 The amount of insulation coverage affects the durabil-ity and abrasion resistance of the insulating material. Applica-tion conditions should be discussed with the manufacturer toaddress these needs.7.3 Dimensions and Finish:7.3.1 The maximum outside transverse dimension as sh
27、ownin Fig. 1, including outer covering of insulated duplex thermo-couple wire, shall not exceed the dimensions given in Table 1.7.3.2 The duplex insulated thermocouple wire shall becapable of being wound around a mandrel having a diameter of1.5 times the maximum outside dimension (Table 1) withoutcr
28、acking or fracturing of the insulation to an extent visible tothe unaided eye.8. Packaging and Package Marking8.1 The insulated thermocouple wire shall be packaged forshipment in containers that will protect it from physicaldamage and moisture.TABLE 1 Maximum Outside Transverse Dimensions of Insulat
29、edWireUninsulated ThermoelementDiameterMaximum Outside DimensionsGage(AWG)NominalDiameterClasses A, B, E andFClasses C and Dmm (in.) mm (in.) mm (in.)20 0.8 (0.032) 2.7 (0.105) 4.5 (0.180)22 0.6 (0.025) 2.3 (0.090) 4.1 (0.160)24 0.5 (0.020) 2.1 (0.080) 3.8 (0.150)30 0.3 (0.010) 1.7 (0.065) noneTABLE
30、 2 Maximum Recommended Continuous UseTemperatures for Insulating MaterialsMaterials Temperature CommentEnamels andimpregnants200C (400F) May be used to 500C (930F) withdecomposition and color loss inhot zoneE-Glass fibers (notimpregnated)340C (650F) Retains 75 % of tensile strength,softens at 730C (
31、1350F)S-Glass fibers (notimpregnated)395C (750F) Retains 80 % of tensile strength,softens at 850C (1560F)Amorphous silicafibers (notimpregnated)980C (1800F) NonePolycrystalline fibers(not impregnated)1250C (2200F) NoneE5740628.2 The insulated thermocouple wire shall be wound onspools, one continuous
32、 length per spool. The purchase ordershall specify accessibility of the inner 3 m (10 ft) of insulatedwire on the spool, when required by the user.8.3 The minimum spool core diameter for fiber insulatedduplex thermocouple wire shall be 50 mm (2 in.).8.4 Spools or inner packaging shall be marked plai
33、nly withthe following:8.4.1 Thermocouple type,8.4.2 Thermoelement diameter,8.4.3 ASTM specification and insulation class,8.4.4 Manufacturers name,8.4.5 Length of wire on spool, and8.4.6 Thermoelectric tolerance (standard or special).9. Quality Assurance Procedure9.1 This specification recognizes the
34、 need of quality assur-ance and control of product being supplied. The level of qualityassurance requirements, enforcement, and documentation mustbe determined by the application and specified in the purchas-ing documents. Table 3 lists the tests which shall be performedon the specific lot of insula
35、ted wire furnished, when specifiedin the purchase order:9.1.1 The absence of specified testing does not relieve themanufacturer of the responsibility to supply material meetingthe technical requirements of this specification (excludingSupplementary Requirement S1). The manufacturer may per-form any
36、of the listed tests and any other test deemed necessaryto ensure the quality of the material. The user may perform anyof the listed tests (see above) as the basis of acceptance.9.2 The test covered by Supplementary Requirement S1shall be performed by the manufacturer when specified in thepurchase do
37、cument.9.3 The manufacturer shall supply the following whenspecified in the purchase document:9.3.1 A statement of compliance certifying that all materialsupplied is in accordance with this specification, and9.3.2 The results of specified tests.10. Keywords10.1 amorphous silica fiber insulated wire;
38、 duplex insulatedthermocouple wire; glass fiber insulated wire; glass insulatedthermocouple wire; insulated thermocouple wire; polycrystal-line fiber insulated wire; thermocouple wireSUPPLEMENTARY REQUIREMENTSThe following supplementary requirements shall apply only when specified by the purchaser i
39、n theinquiry or purchase order.S1. Resistance TestS1.1 The finished Classes A and E duplex insulated wireshall be capable of passing the following wet insulationresistance test (Note S1): A sample of wire at least 300 mm (12in.) long shall be bent at its center 180 around a 13 mm (12 in.)diameter ma
40、ndrel to form a U-shaped loop with straight sides.S1.2 The loop shall be immersed to a depth of 50 mm 6 6mm (2 in. 614 in.) in 25 C 6 2 C (77 F 6 4 F) waterhaving a resistivity (Note S2) of not more than 1 3 103V-cmfor at least 10 min.NOTE S1The purchasing document may specify an alternate wetinsula
41、tion resistance test which has been agreed upon by the purchaser andthe manufacturer.NOTE S2The resistivity of water shall be determined in accordancewith Test Methods D 1125.S1.3 The wet insulation resistance will be acceptable if thecurrent is less than 50 A when 180 V dc is impressed betweenthe t
42、hermoelements or a megohmeter meter measures morethan 3.6 3 106V resistance when a minimum of 200 V dc isimpressed between the thermoelements.S2. Precision and BiasS2.1 Wet insulation resistance measurement in the supple-mentary requirement is primarily used to determine the mois-ture resistance of
43、the insulated thermocouple wire over aspecified arbitrary time period. Both parties should concur as tothe sampling procedure prior to undertaking this pass or failtest. Consequently, statements of precision and bias are notrelevant.FIG. 1 Transverse DimensionTABLE 3 Tests to be Performed when Speci
44、fied in the PurchaseOrderTest ParagraphSize Verification 7.1.2, 7.3.1, 8.3Calibration 7.1.3Insulation Quality 7.3.2E574063ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expre
45、ssly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised
46、, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may a
47、ttend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).E574064
