1、Designation: E 1214 06Standard Guide forUse of Melt Wire Temperature Monitors for Reactor VesselSurveillance, E 706 (IIIE)1This standard is issued under the fixed designation E 1214; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、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 guide describes the application of melt wire tem-perature monitors and their use for reactor vessel
3、surveillanceof light-water power reactors as called for in Practice E 185.1.2 The purpose of this guide is to recommend the selectionand use of the common melt wire technique where thecorrespondence between melting temperature and compositionof different alloys is used as a passive temperature monit
4、or.Guidelines are provided for the selection and calibration ofmonitor materials; design, fabrication, and assembly of moni-tor and container; post-irradiation examinations; interpretationof the results; and estimation of uncertainties.1.3 This standard does not purport to address all of thesafety c
5、oncerns, 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. (See Note 1.)2. Referenced Documents2.1 ASTM Standards:2E 185 Practice for Des
6、ign of Surveillance Programs forLight-Water Moderated Nuclear Power Reactor VesselsE 706 Master Matrix for Light-Water Reactor PressureVessel Surveillance Standards, E 706(0)E 794 Test Method for Melting And Crystallization Tem-peratures By Thermal AnalysisE 900 Guide for Predicting Radiation-Induce
7、d TransitionTemperature Shift in Reactor Vessel Materials, E706 (IIF)E 2215 Practice for Evaluation of Surveillance Capsulesfrom Light-Water Moderated Nuclear Power Reactor Ves-sels3. Significance and Use3.1 Temperature monitors are used in surveillance capsulesin accordance with Practice E 2215 to
8、verify the estimatedvalue of the surveillance specimen irradiation temperature.Temperature monitors are needed to give evidence of overheat-ing of surveillance specimens beyond the expected tempera-ture. Because overheating causes a reduction in the amount ofneutron radiation damage to the surveilla
9、nce specimens, thisoverheating could result in a change in the measured propertiesof the surveillance specimens that would lead to an unconser-vative prediction of damage to the reactor vessel material.3.2 The magnitude of the reduction of radiation damagewith overheating depends on the composition
10、of the materialand time at temperature. Guide E 900 provides an acceptedmethod for quantifying the temperature effect. Because theevidence from melt wire monitors gives no indication of theduration of overheating above the expected temperature asindicated by melting of the monitor, the significance
11、ofoverheating events cannot be quantified on the basis of thermalmonitors alone. Indication of overheating does serve to alertthe user of the data to further evaluate the irradiation tempera-ture exposure history of the surveillance capsule.3.3 This guide is IIIE of Master Matrix E 706 that relatess
12、everal standards used for irradiation surveillance of lightwater reactor vessel materials. It is intended primarily toamplify the requirements of Practice E 185 in the design oftemperature monitors for the surveillance program. It may alsobe used in conjunction with Practice E 2215 to evaluate thepo
13、st-irradiation test measurements4. Selection and Calibration of Monitor Materials4.1 Selection of Monitor Materials:4.1.1 Materials selected for thermal monitors shall possessunique melting temperatures. Since composition, and particu-larly the presence of impurities, strongly influence meltingtempe
14、rature, the fabricated monitor materials shall consist ofeither metals of purity 99.9 % or greater or eutectic alloys suchthat the measured melting temperature is within 63C of therecognized melting temperature. Transmutation-inducedchanges of the monitor materials suggested in 4.1.2 are notconsider
15、ed significant for fluence exposures to 1 3 1020n/cm2(E 1 MeV) relative to the goal of these thermalmonitors in flagging deviations from expected temperatures.1This guide is under the jurisdiction of ASTM Committee E10 on NuclearTechnology and Applications and is the direct responsibility of Subcomm
16、itteeE10.02 on Behavior and Use of Metallic Materials in Nuclear Systems.Current edition approved Jan. 1, 2006. Published February 2006. Originallyapproved in 1987. Last previous edition approved in 2000 as E 121487(2000).2The reference Master Matrix designation in parentheses refers to Section 5, a
17、swell as Figs. 1 and 2 of Matrix E 706.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.1.2 The monitor materials in Table 1 provide temperatureindications in the range of 266 to 327C. Other metals or alloysmay be selected for the t
18、emperatures of interest provided themonitor materials meet the technical requirements of thisguide.4.1.3 The chosen monitor materials shall be carefully evalu-ated for radiological health hazards.NOTE 1It is beyond the scope of this guide to provide safety andhealth criteria, and the user is caution
19、ed to seek further guidance.4.2 Calibration of Monitor Materials Each lot of monitormaterials shall be calibrated by melting tests to establish theactual melting temperatures. The melting temperature testsshall be conducted in accordance with Test Method E 794.Ifanalternate method of calibration is
20、used, the procedure andequipment must be described, the resultant mean values anduncertainties must be reported, and traceability to standardsmust be declared.5. Design, Fabrication, and Assembly of Monitor andContainer5.1 The design of the monitor and its container shall ensurethat the maximum temp
21、erature of the surveillance specimens isdetermined within 610C.5.2 The design shall provide for a minimum of one set ofmonitors for each surveillance capsule. Additional sets ofmonitors are desirable to characterize the in-service axialtemperature profiles necessary to determine the maximumtemperatu
22、re of each surveillance specimen.5.3 The design of the monitor and its container shall ensurethat the monitor will readily sense the environmental tempera-ture of the surveillance specimens and yet not be subject to anyinfluences from fabrication or assembly or even post-serviceexamination. The moni
23、tors typically consist of melt wirespositioned adjacent to or among the surveillance specimens.5.4 The quantity of monitors within each set shall beadequate to identify any temperature excursion of 10C up tothe highest potential temperature, such as 330C. It is recom-mended that monitors be selected
24、 to measure temperature atintervals of 5 to 12C. At least one monitor shall remain intactthroughout the service life; therefore the highest temperaturemonitor must possess a melting temperature greater than thehighest anticipated temperature.5.5 Fabrication and assembly of the monitors and container
25、sshall protect and maintain the integrity of each thermal monitorand its ability to respond by melting at the environmentaltemperature of the surveillance specimens corresponding to themonitors melting temperature. Design and fabrication mustensure that the monitor in the assembled container does me
26、lt ata temperature within 63C of environmental temperature ofthe specimens.5.6 Identification of each monitor, its material and meltingtemperature, and its orientation and location in the surveillancecapsule must be maintained. Provision for means of verifica-tion shall be done by design.6. Post-Irr
27、adiation Examination6.1 Following irradiation, the temperature monitors shall beexamined for evidence of melting to establish the maximumexposure temperature of the encapsulated surveillance speci-mens. Precautions should be taken while recovering the moni-tors from the surveillance capsule and duri
28、ng subsequentexamination.6.1.1 The monitor design and method of encapsulation shallbe considered in the recovery procedure to ensure that themonitors are not damaged and that the original identity ofindividual monitors and their location is maintained.6.1.2 Recovery and examination of the monitors s
29、hould beperformed remotely or with sufficient shielding to protect theoperator from unnecessary radiation exposure.6.2 Evaluation of the temperature monitors after service forevidence of melting should be performed using suitable equip-ment that is dependent on the design of the monitor containerand
30、 the examination facility. When visual inspection of themonitors is possible, such as with periscopes, each monitorshall be examined and the results recorded. When possible,photographic records should be made of each monitor or set ofmonitors. When visual inspection is not practical or conclusive,ra
31、diography or metallographic examination may be necessary.Destructive examination should be performed only if furtherconfirmation of the melting temperature is necessary.6.3 The monitors shall be evaluated on the following basis:6.3.1 UnmeltedNo evidence of melting of any portion ofthe monitor.6.3.2
32、Partially MeltedAny evidence of any melting ofany portion of the monitor.6.3.3 Fully MeltedEvidence that all of the monitor wassubject to melting.6.4 If there is reason to question the results, monitors shouldbe reevaluated after completion of the post-irradiation exami-nation to ensure that there w
33、as no change in the meltingtemperature. This verification of melting temperature may beperformed as described in 4.2.7. Interpretation7.1 The design of the melt wire configuration should pre-vent ambiguities as to incipient melting. However, there maybe circumstances where melting is questionable. C
34、hange inshape, slumping, and segmenting are indications of melting.When initial examination results are uncertain, that fact mustbe documented. Further nondestructive and destructive exami-nations may be performed if warranted to verify the conditionof the monitor.7.2 The condition of the monitors s
35、hould be consistentaccording to axial position and expected relative temperatures.7.3 Based upon the temperatures indicated by the thermalmonitors, the temperature of surveillance specimens must beTABLE 1 Monitor Material Melting TemperatureMonitor Material, Weight % Melting Temperature, CCd17.4 Zn
36、266Au20.0 Sn 280Pb5.0 Ag5.0 Sn 292Pb2.5 Ag 304Pb1.5 Ag1.0 Sn 309Pb1.75 Ag0.75 Sn 310Cd1.2 Cu 314Cd 321Pb 327E1214062ascertained and documented. The temperature relationshipshould consider the design of the monitor and container, theconfiguration of specimens relative to the monitors, andpotential th
37、ermal gradients.7.4 Abnormalities between the thermal monitor results andhistorical service conditions shall be assessed and described.8. Estimation of Uncertainties8.1 Results should be given as best estimates with knownuncertainties. Uncertainties arise from limitations in precisionand bias in det
38、ermining the initial melting temperatures of eachmonitor, the ability of the monitor to accurately indicate theenvironmental temperature, the relationship in temperaturebetween the monitors and the specimens, and the bias indiscriminating melting.8.2 All known and estimated uncertainties, including
39、adescription of their determination, must be reported with theestimated maximum exposure temperatures.8.3 Uncertainties resulting from unresolved ambiguitiesmust be described. Probable causes and subsequent implica-tions should be stated.9. Report9.1 In addition to the reporting requirements of Prac
40、ticeE 185, the following information shall be reported:9.1.1 Description of the thermal monitors including chemi-cal composition of the monitor melt wires and their respectivemelting temperatures with uncertainties, container design,identification, and location in the irradiation capsule.9.1.2 Resul
41、ts of the post-service evaluation in which eachmonitor condition is characterized as fully melted, unmelted, orpartially melted.9.1.3 The estimated maximum exposure temperature ofeach specimen and the known and estimated uncertainties.9.1.4 The agreement between the thermal monitor resultsand the hi
42、storical service conditions and description of anyanomalies found while recovering, examining, or evaluatingthe monitors.9.1.5 Results of any additional examinations, if performed,to resolve inconsistent monitor results.9.2 The following additional documentation should be re-ported if performed:9.2.
43、1 Photographs of each irradiated temperature monitorthat document the visual observations.9.2.2 Preirradiation test results used to certify meltingtemperatures of each monitor type.9.2.3 Test results, if performed, verifying post-irradiationmelting temperature for each monitor.10. Keywords10.1 nucle
44、ar reactor vessels; neutron irradiation; surveil-lance (of nuclear reactor vessels)ASTM 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 expressly advised that determination of the
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47、ave 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).E1214063
