ML20148Q198
| ML20148Q198 | |
| Person / Time | |
|---|---|
| Issue date: | 01/02/1981 |
| From: | Arlotto G NRC OFFICE OF STANDARDS DEVELOPMENT |
| To: | Fraley R Advisory Committee on Reactor Safeguards |
| References | |
| REF-GTECI-A-14, REF-GTECI-PI, RTR-REGGD-01.XXX, RTR-REGGD-1.150, RTR-REGGD-1.XXX, TASK-A-14-5-4, TASK-OR, TASK-OS, TASK-SC-705-4 NUDOCS 8101210322 | |
| Download: ML20148Q198 (39) | |
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P D 2-VNitt0 STATIS
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i, NUCLEAR REcULATORY cOMMisstCN W ASHINGTON, Q. C. 20S$$
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MEMORANDUM FOR: Raymond F. Fraley, Executive Director, ACRS - ?
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FROM: G. A. Arlotto, Director, Division of Engineer 16g Stand'ards, 50i
SUBJECT:
ORAFT (OCTOBER 1980), REGULATORY GUIDE " ULTRASONIC TESTING 0F REACTCR VESSEL WELOS OURING PRESERVICE AND INSCRVICE EXAMINATION" (TASK NO. 5C-705-4)
Enclosed for the use of the Subcomittee on Regulatory Activ'ities are 15 copies of Oraft 2 of the proposed regulatory guide, " Ultrasonic Testing of Reactor Vessel Welds During Preservice and Inservics Inspection."
This guide was initisted as a result of a request from NRR and is also a scheduleo milestone in Task Action Plan A-14, " Flaw Detection and Characteriza-tion." This proposed regulatory guide provides supplementary guidance to the ultrasonic testing (UT) procedures specified by the ASME, B&PV Code, 1977 edition, fer the inservice inspection of reactor vessel welds. .
- Also enclosed herewith are 15 copies each of (1) the letters of public comments, (2) a sumary of public coments and their resolutions, and (3) the Value-Impact Statement.
ACRS concurrence in the regulatory position request .
(
Guy A . Arlotto, Director Divis lon of Engineering Standards Offic( of Standards Deveiopment
Enclosures:
As stated cc w.encis:
V. Noonan, DE, NRR S. Pawlicki, DE NRR F. Schroeder, DST, NRR C. Cheng OPM, NRR M. Hum, OE, NRR W. Hazelton, OE, NRR G. Knighton, DST, NRR 1
l THIS DOCUMENT CONTAINS 8101210 hk POOR QUAUTY PAGES
December 18. 1980.
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RI AC108t VIS%t WitDS DuelleG INSER71CE EXAMit Allusi A. INIB00UCIl004 Criterion 1. "4 aality Standards and Records." of ftppe ,
- General Destget Criteria f or thsclear Power Plants," to its Cf R Par , stic ticenstrug af Pso&mttom and Utiltration f acilities," n%{ in part, that components imeuertant to safety 1,e tested to 11 . andards s e==.n-surate with the importance of the safety futattlonsig#herformed. Where generally seco<pilied codes atut standards are a t codes and standards must lae evalasted to detesmine their adeepsa ficleticy aful must lie sappienesited or modllled as necessary to s lity product in keeping with the required saf ety f usttlen. Crlt further retystres that a agatality assur.tn(e 3,rugram lae implene order to provide adequate asstar-ente that tl.ese components will Qg r ly perform their safety functlens and that agtsupriate secords of te t ting of compessents leportant to safety be malatals.ed by or seider t non af ti.e nuclear power esalt licensee t hs ouglieut f lee life si tlee it.
Section 50 554, " Codes 3 - tanutards," of le CI A Part 50 retystret, la part, that s't s uc tuses, systems, and cesponents be desigand, f abricated, erected, constsue.t Qtuted, and inspecteJ to sguality standards commenstarate * '
with it.e importai Q T k safety function to be performed. Section 50.55a f urther se. pal dPih YAtta Boiler and Pressure vessel Code (A5ML B&PW Code)
Class ! coyot etjts eet the requirements set forth in Sectlen II. " Rules for laservicf 3ptetl on of Huclear Power Plant Components," of the A58tt Code.
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- s Crites tem Ill. "Canntrol of Meessering aesd last Equlgment." of Appen-dla B. " Quality Assurante Criteria for iluclear Power Plants and fuel Reprocessiruj Plants." to IS Cf a Part 58 requires, la pas t, that measures *
't.e established to ensure that lastruments used in activities affectlag quality are peeperly contrulled, cellbrated, and adjusted at specified 9
- such perleds to maintain accuracy withis necessary limits- #
Criterlun XVil. " Quality Assurance Records." of Appendix 8 requires.
f la pas t, that suiticient records be malatained to furnish evidence of 1 % Delete I' activilles allecting quality. Consistent with applicable regulatory I
sequirements, the applicant is required to establish requirements costerning J
s ecord setentlen @ as duration, location, meat ass gned responsibility. by ultrascalc testing (Ul).
lhis guide describes procedures acceptable to 'the leRC sGM eis~Einteria basis for laplementing the a*. eave requirements ultti regard to the gareservice red laservice e= amination of reacter vessel welds la light-water-cooled nutlear power plants [the scope of this guide is Ilmited to reacter vessel **
welds anni does not apply to other structures and camponents sucle as piping.
- g. 915tus51014 reactor vessels. it is essentiel that flaws be reliably detected asul evaluated.
it is desirable that results (res prior Ul examlastions be compased to results Iteactor vessels must periodically be volumetrically examined according " *H gma rates may be edisated Lad to Settless El of ti.e A581 Code, which is lacorporated by refereswe, settla *I F8 IllLF #f UI emaninetion results is partly due to the reporting of The rules of Sec. 8" "' " ** such as seportleg the length of flaws to be shutter *kiring leWC staf f maalifications la 650.55a et le Cf t Part 50.
tisa Il se.psire a psogram of examinations, testlag. and inspections to 6 ** W ht *maal**tlens. Ns lack af reproducibility arises 1,ecause LI.e Code evidence adequate safety. le ensare the continued structural lategrity of " F89" ***" 5 *r* not specific about meey essential'vertables 8n the ut prete-reactor vessels. it is essential that Targ'e ll&it 6eleliably detected es.g -
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ures- ecemmendattens of this spaide provide Guidance that would leelp to obtain e
evaluated it is desirable that sesults may be compared from one ultrasonic repro <lucibility of results. Reporting of lil Indications as recommmeekled in this testing (Ul) emaninallen to the other so that flaw growth rates asy 14 guide will help to provide 4 means for assessing Lte ambiguity el the reposled estimated tad al reliability of UI esamination results is partly due to data' the res* sting af ambiguous results. Reporting of UI indications as recet:- #
metaled is. thils guide will help to provide a means for assessing time amteiguity of the sepasled data.
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,gfay- MSS A T I have Operating ami licensing empertence [* asul ladustry tests ladicated that Ul procedures Lt at have been used for emantnetton[may not be adequate to (enststently detect and reliably characterise flaws sharlag in eswice emaninattom of seactors. Ibis la<k of reproducibility of locatti.n and ca.aruterisation of flaws has resulted la the steed for additional emanina-
-tions asal evaluations witti associated delays in the licensing process. --- A Delete ( This has been laserted in S 7)
-) Delete f1. psikwegl rulosevwt tutCts l. lu5inmuul stilllt PtatemeustE CMCE5 Instrement system performance chects to deteralme Line chara2teristics el the UI system should be performed at latervals short emuugh to pesmit eath Un Ihis guide gives reconneemlations for recording the characteristics of examinatloa to be correlated with particular system periosmance parameters to the Ul esamination system. This information can be of sigellicence in later analysis for deteseining the location, dimensions, erleatation, ar.d growtli help compara results. Iliese detesalnattens will help mate it possible to judue wlether diffesences la observattens made at different times are due to thanges t rate of fl e ~
la the lastrument system characteristics or are due to real changes in the flaw System pes f asmasme 1 $ .ecks to determine the characteristics of tie UI sys-size ami characteristics. Detesminations for "f reequency Amplltense Curve" and tem st#;uld be pertoimed at latervals close enough that e u h UI examination I " Pulse shape" recommended in Penttlems C.1.3 and C.1.4 may be made t y ti.e say lee terrelated witti particular system performance parameters to help com-licensee's emanination agent by the asse of any of time common ladesta y methods pare sesults. these deteseinations will help mate it possible to judge whether dif f esentes in observallsas made at dif ferent (lees are due to changes for measuring these parameters as long as it is aJealisately documented in the examination record. linese measurements may be performed in the laboralas y
! la lastrument chasatte:rlstics or are ilue to real changes in the flaw size and 4 before and af ter eule emaelnation, provided the identical equlgeent combination theracteristics.
-s (i.e., lastrimentation, cable, aad search eentt) is used iksrls g the easelnat tusi.
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- 2. C Al ltikAll,0st k these determinations ase to aid third party evaluettosis wl.en diffesent equipment is used to record ladications en sidesequent esamlaattons, ais.8 ase Acceerding to Appesulla I, Article I, I-4230, Section El of the ASM met intended to apaalify systems for ease.
Code, 19/4 edition, instriseesat calibration for performance characteristics the intent of Position C.I.4 la to establisti the instrument pulse shape (amplitude lineas Ity ami amplitude control linearity) is to be wetifled at la a way ti.at actual values of pulse lengtle end voltages can be elsserved on an I" ultrasonic Neinspetiluu of Pilgrie ! Reactor Vessel liozzle 1828," Jol.a 11. oscil Sscope. lhe calibrated time base does not necessarily liave to follow Gleste, talRIG-6502, the time base of ti.e distante amplitude correction (DAC) curve but. may be "Summ.n y llattle H n. lear Plant Unit i Reuter Ps essure Yessel Repair
- 1972, thosen to suitably charuterlie the lultlal pulse. Pulse shape neton'd will 1.corgia Power tempany. assist in analyzing gmtential dWerences la flaw respouse between suttessive "5 ammary of ti.e Detettien ami f eatuation of Ultrasonic ladications - fabeln examinations (ls it flaw growth or system change).
limith Unit I kenter Psessus e Vessel," January 1972, Georgia Power Company.
Nousul subin tests conducted by the Pressure Vessel Researth Committee Pulse Shape is leest determined by using a higle-impedence oscillosa pe wilia (PVNC) of the Weldlag Researcia Council for UI of Dilck settlon steels. the transducer disconnected from the lastrissent.
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the beglanlag of each day of ananlaation. Reepelsements la Article 4. Sec-tien V.1911 editten, weittin is referenced by Sectlen II for the perledic the(k of lastrisees.t (kaacteristics (screen belght liseearity, amplitsman - p gg, control linearity, ar.d beam spread messierements) for Ul esamlaatlea of reactor T
peessume messels b e been relamed. Jihls periodic chett has beest extended frue I day to a perlei el entes7ed use er every 3 months, editchever is less.
Ibis thange has s et t.een justified en time basis of statistically significant \
i ifteld data. Stability of automated ele <.tronic e gul; ment is depesident en ,
r many f atters. asul the A58f Code has no spaality stasidards en the camponents of these systems. thetit stability of periesmance of til systems can be '
ensused by the introduction of ersality standards for all components. It is not reasonable to ism.rease Llie perloal 4.etween caill ratloa clie(ts. liierefore$j J lhe laterval bettseen perledic checks has been eatended f rom a period of a day .
lhls change secuesmindations have been maJe to check f astrisment (bracteristics more ; to a period of entended use er every 3 seaths, editchever is less,
_!s ewsent iv th_.n specllied se the a s a s r se. _
l has not been hastifled en the basis of statistically slyillicaat field data.
itehlsements of Appendla 1. Article'I.1-4250. Settlen II of the Aseg Performance stability of eaetomated electrealc eaystpomat is depesident een systes foJd. 1914 edition, state: performance parameters (essential variables). W the A5ft M hs att Mty ifying the distance. thetit stability of perfor-standards to centrol these performence parameters.
"5ystem calibration shall be checked bamplitiale 4520) sos section curve (1-4420 or bwer and the sweer 1
asuge talibration (I-4410 er I-4519) at the start and fiolsh mance of Uf systems can he ensured by the latro. tinction of traality standasds.
< there-of eatl. ex.ainatten, witti any change la enantsiation persosumel, It ls s,ot reaseamble te lacrease the perled between calibration clietts.
and at least every 4 leours iluring an examination."
fere, recommendations have been sade to check lastrtment perfoematite parameters la the 1911 edition, tliese respelrements were chnged. According to more f resguently than is specified in the A5ftE Code.
As ticle 4 (1-412.1.2). Section \' of the A58f Code.1917 edilloa. the fellow-lius asylles:
"A tallbratiosa check on at least one of the basic reflectors la the basta. tallbsallen bleek er a cheth using a slaulator shall One Polas Cheth.
e be made at the finish of each examtmation, every 4 hr. durinit '
lle exami.ialinsi anul idies. examination persoeunel are changed.*
thh seguirement Ms several elseer eseficiencies, including the falleula.s:
a.[ Caliha ation (i.eck is gow requiseni on only one of the basic refleEters.
As a se w it. the muuracy of only one point on the@lanceMllude Correction' hAth auswe, and dtI~e. suuracy of three points as psevloissly resguired, is thetteJ. this alteration would pensit the instrument drif t for attier nietal path distantes to ua ammuticed, which is siot desirable. , , , _ , -
. g,Ja_rr lieference.
te [the (6nge allows a one pelat cl.eck by a me(1 amical or electrealc slaulator lusteaJ el a the(k against Lt.e liasic calibration block. A mechanical 1
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> Delete simulator could t.e a plastic, steel, or elsenisaan block with a single referesste c. Electronic Simislater, reflector, which may I.e a liule or a notch. Without specified details, the Sisbatticle I-432.1.3 et Article 4,Section V of the AMIE Code, 1517 edi-elettronic simulator could be any device that provides an electrical signal. tien, allems tlie use of an electamalc simulater and also penalts the teens kner Witti the eesulting neuertainty, Lliere may be errors la checking agalast somsttivity Le be c.hecked separately. Seth of timese prowlslaas may lateeduce ll.e secundary setesence (simulator), the magnitude of which is inndefined errors that w$ll be very dif ficult te detect, i
anduntsyam. _ _ _ _ _ _ _ _ _ . _ _ ____=_-- . -
M c. 5uttarticle I-432.1.3 ef Article 4,Section V et the A9E Code, le aveld the intradiactien of errors ased to ensenre repeatatillity el emanina-j 1911 edition, allows the use of an electronic simulator and aise pemits tieses at a later date, it would be advisable to clieck tb catthration of the ;
the tsansdater sensitivity to be cliected separately. Seth of these pro- ' entire system rather than that of individisal tempesients. Checking System calibra-vistans mey intseduce errors that will he very dif ficult to detect for the Llan wittneut the transducer anal the cable is met advisable, as these tests de feltuulng seasesis: not sietect possible leakage er resistance changes at the cesnectess, lhls is fI) Ihe slaulater amt its applicatlou are not defined. Ilmither especially lapos tant winen the UI examinatlea la perimmed immler conditions of ase ti.e electeunics parameters ar their roepaired stability specified Until ,
high humidity or useiler water ased the connectors may eat be watesproot or ll.e at>ove parametens are defined and the l'nulse voltage is checked against muistiereproef. Chechtsig time transaliscar sensitivity separately (sometimes wn:eks a standard souste of sef esence, time electrealc simulator should not be used. In advasice) also singlects the ef fects of possible damatam alue to transport or U) then. ting the trasiseliscer sensitivity separately sieglects time ease. Eine trasisducer characteristics may chiasegge lamaisse et dasia<je to un degeada-'
ef fects of brnkesi thips, verlatless in epoxy (ontaci bond, and trasisducer ties of laternal bonding agents er inadvertent damage to the tsansikmer element.
a ps e ' against the tempenent, which af fects coupling azul variatlosis or fierther, the use of an electronic block simulator (ER5) as a secondasy staalard -
f aults la coupt img cons.etters.. tintil guidance #s provided to evold time latroduces an error band in thee callbratten process. Ihis error bamt may depenet etiett of these variables, it is seet advisable to check the transducer on, among others, the intlawing facters: .
7 sensitivity sepasately. (1) Brlf t akse to ambient temperatista cleange.
- d. Calihaation Checks (2) Bellt alue to bl@ teceatiste Llorage.
(1) *cannin.l_5gsed.
. Ihe resoluttua capability of til systems I (3) Brlf t ekse te higli humidity storage.
may 1,e dependent on the scasuilng speed becaesse of time (a) Increase in track- k (4) Drif t shas te vibretten end slauck loadisig aberlavl shipment, ing mutur via. rations f or automateil esysipment and (b) variatlosis les cositact (5) Degradatlosi esul resissiluct ion ca6*acity *f ties an nmary device use.1 to forte ama liesw e eupliml ef ficiency betueen time transducer and the metal. j store Llie reference algual Information shse to vibration, shock, aglug, l Ihese sesolution capal llity alliferenices may f ailroduce errors winess ilie calllira- f or tient effects.
ties is done 1,y a hased-held static trasisducer anel scansitsig is gierformed by le ensure stability, campester systems are geenerally kept I.a an air tundl*
automated e<psipmesat, or iluring a masissal scan when the callieration is done tiened envisusamesit; lion.ever, this is seet gesserally desse for 185 systems.
with a static ta ansik.cer and scasuilng for flau detection is through a moving Error land for one particular type of lastressent was detesmined tu lee in transdocer g the range of ab%. line errer banit for other lastrimments may be las a difierent f or the alove reasosts, callieration sinuuld be lierfoameil by a enving transihn.er when line seference BAC cusve is to be used f or L!ae nietec- g , 5" Calibration Verificaligt of Ultrascalc Examination Systems with the Electionic
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- Sleck Slaulater, by D. J. Bocagesd, et al., August 1979 Seport No. WCAP 4545, tion of flaws. f or f lat. stdng by the manual method, static calibration .j niestisujausse Electsenic Corporation,11sclear Service DivIslon, P.O. Box 2128
) - Pittsleurgli, PA 15238.
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,a' range anat may vary ier the same iastrimesat if memory deeice6 or cinsponent6 o8 dif ferent eguality are insed at a later date. Ibe eerer I.asma is dependent en the temperature entremes, shock loadings, and vibratlans sultes ed by ti.e lastsu-ment. innce Lt e error band value depends en these parameters, it would be advisable to ensaare, through recordlag lastrements, that ti.e TBS was anot subjected to biglier temperatures (container lying la the susa) and greater shock (container dropped) diaring transport than these that served as a inasis ter defining the errar banal.
Use et electronic simulators weasld be permissible if they can ct.cck the calibration of the lit system as a idente and the error band lutream.ed by their use can be relled on and taken lato consideratloa.
- d. Static versus draanic reflector rewmeises With some automated systems, the BAC curve is - Ily establisheJ by maalaising the sipal by optletalag time transdiacer erlentation towasd the callbration I. oles. Subsequently, detectlam and sizing of flaws is em Llw basis of signals (nelve
- f rom a movin0 transducer meere no attempt is made (or it 8 is not possible) to maxialze tNs signal even for significant llaws. II.l s procedure neglects several sources of error latroduced by time possible varia-tion la signal strength caused by:
(1) Dif ferences betueen the maalalted signal and the unmanlaired signal.
(2) toss in algstal stre*0th due to ti.e separattom af tiae teasaducer from the metal surf ace because of the wiscestly of the coupilsig medlie (planing effects).
(3) Variatten la contact ferce aid transducer coupling elficie,ay.
(4) toss in slynal strength due to struettural vibration ef f ects les time moving transducer anunt eM ether driving e.echanisms.
($) loss la signal strength elue to the tilting caused 8 y the miunting arrangement in some treasducer mounts.
Because of the above, it would f.e advisable to establish the I:AC turve assuler the same coenittlosis as those emeder tAttch scar.ning is pes formed to obtala data for detection and slalog. It would be aceptable to establish a DAC curu by maatalatng signal sisengtli during manuas scans ideen signals ase also maxi-elred for flau slaing. Iluwever, it woul<A not be adels ble to use manually maalained siginals to establisin tie DAC curve entiend ' ata age obtained later by mechanized transtlucers (tdmse signals cannot be maximized) for tiie detes.tlun t
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a range asmi may vary for the same lastrument 8f ammary devices or compements of different quality are used at a later date. the error band is deswedent en the temperature entrzees, shock leadlags, and vibret tees suf fer=J by tsie lastsu-meat. $ lace the arrar baas valese depeads en these parameters, it wund be advisable te ensure, through recordlag lastrinnents, that the 185 w s not sednjected to higher Leereratures (ceatalmer lylag la the sun) and greater stak (container dropped) durlag teansport than tb se that served as a 1.asts for deftalag the error band.
Use of e ectronic simulators would be perialssible if t'sey can check the calibratlea of the lit systes as a dele and the error based latrihed by their use can lie rel!ed on and Laten late considerettaa.
- d. M ic versus draanic reflector ressicases Idith some autenated systems, the SAC cierve is == ally estellsted by maalalalag the signal by 9tfatalag the transducar erleatation towa.J the calibrattaa holes. 54 Sequee.ily, detectima and sirlag of fleus is en tie basis et signals receivee free c nowlag transducer =lhere ne attempt is made (er it is met possible) to samtalaa time signal even for significant flaws. Ibis procciksre neglects several sources of error latroduced by at. possible varia-
- lon la signal stsength caused by-(1) Of tfesences betueen the maalataed signal and the inumaaleized sly al.
(2) loss les algaat strength due te Ge separattom of the traastner tross 4
the metal surf ace because of the wiscosity of the couptlug nedhe (plaats.g effects).
(3) Varlation la coalact force and transducer consellag ef ficienty.
(4) less in sly at strength ehes to structural vibrstlen ef fects lu time noving traensducer muemat and other etrlwing mechaelsas.
(S) loss in aignal strength ekse to the tilting caused by the moaatiieg arsangement la same transducer moear.Lt.
liecause of the above, it would be advisable to establish the bAC curve esader the same condittoms as these under tAnich scanalag is perfumed tu oblates data for detection and staleig. It would be acceptable le establish a DAC curve by maatelalag signal stresagth during maenual acans ideen slyuls are also maal-mired for flau slalag. Ilowever, it would not be advisable to use mesmaally maalalted slytels la establista the DAC curve idten data are obtained later by mechaalted transducers (idiese signals cannet be aanlaised) for the detectica {
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h and slatng of flaus without adjustment for the potential error introdoted in these situatleas, an acceptable method would be to establish DAC curves uslug moving transebacers or establith correctlaa facters =4mich may be used to adjust signal strength. It would be advisable to use care aand plan, ting in estahtishlag carrection factars. f or example, 6stablishlag a ratto betmeen a dynamic asal static nude esider laboratesy condittens uslag a precision transducer drive and stiff mounting may have very little la common with the transda er mountisus and traverse condittoms of the actual esamlaatloa setup. U correction fa tors are to be used, it would be wortanskile to build either full-scale muttsys or consider the variatten of all the leportant parameters la a suitable model taslag lato consideration scallag laus on variables such as mass, vibration, and stillness constants. It would tee advisible to confirm it.e scaling law assump-tions and predictlens for vlbratlea and viscosity ef fects beio-e correttluu factors are used for setting scanning sensitivity levels.
Bif f erences in the curvature asul surf ace finish between callt. ration I:luds and vessel areas could change the Jynamic response, so it may be advisible le establish currection f actors betmeen dynamic and static rest onses inom ite ladications that are found during emanination. this mound avoid tlae difficul-ties associated with establishing a dynaalc response DAC curve aemt still take all the factors lato consideration.
l' age b-f w
~ - - -
~ ~ .
f Delete
/- le slalalae -
f may be used if slalag is performed using a static trans=hacer.
the ellett of any vibratleas, the scanning speed should est exceed tiae call-beetles speed uten automated e y lpment is used. for autamated equit *ent.
the scannisus disettien siould be it;e same as the calibratlea directica, unless it can be shawa that change of scasuilag direction does not make a '
d!!tesesm e les tim sensitivity and vibratlee bungroushi aulse received f rom the seas sle sailt, or these dif fermences stwuld be takea late actoimit. Some seartli units have a curved shoe that tends to heel over ut.en the scenalog 4 ,,
k , disectiusi is chammed. tliereby resullisua la loss of retelved slunal.
' Secondary DAC. Durine some manual scans, ti.e end pelat of
- ~ '%f the DAC turve may fall below 20% of the full screen height. E en this bepeos, it la difficult to evaluate flaus on the 201 and 50% DAC basis in this region lo over-sinne the 20% ami 50% DAC points may be too close to the baseline.
- come this ditticulty, it is advisable that a secondary DAC curve using a lhe secondary BAC curves swed not be generated aantess they ase se highergainsettisu[edeveloped6ethat20%and501BACpelatsmaybe easily evaluated. f or this purpose, it is adessable tht the gala lie if electronic DX is used med amplitudes are maletained above 2c% of full sc intseased sutticiently to teep time lowest point of the secondary CAC curve I.elglit, a r.ecessulary DAC woulit not be necessary.
- above 20% of screen f.elght. _ _ ._.--- _ . _ ,
.i ! O g Cnaponent Substituties. A calibration check shos.ld be made
,, gusitimeatoeponentisputbacklateLt.esystemtoensurethatsuchcoepo- I-ments as ts ansducers, g.ulsers, and receivers were not damaged utille they yes e in storage. Ihis will ensure elletaation of ti.e error band and mistakes in sesettisuj the various centrol $nnbs.
'#'(9 f alibration Iksles, temparison of results betueen emaninations
litement times may be fu llitated if the same equipsesit is
.perforstdat used and if the reflections f rom graulng flaus can be compared to ti.e same reference signal. Iteterence signals obtained f rom a calibration black dep.esul 4 en, anung other things, the surf ace roughness of the block and Llae reflector holes. Iheseluse, these surfues should be protected f rom corresloa askt
' mettias.lcal damage and aise sliould sint Ise altered by mechanical er (leemical
, pans betueese successive emanlaations. If the reference reflector Imles or the blod sus fue are given a higts polish by any clutcal or mechaalcal
, measts, tiie ang lltimle of time retle(tlons eletained f rom these retlector laoles may t.e attesed. Fullshing the Isles or the black surf ace is siot f ashidden
'l j.
6 as c.
g 4.s we.m-
I by the A5HL Ende. N wever, this possHely altered amplituds could effect At this klee, ne the slaing of ludicallons found ehiring any enamination.
rewsmetulattuns are beleg made to control tlas surfue rougliness of the block or the almve mentioned reflector holes; liuwever, if the block or these f.eles are pollslied, this f ut should be recorded for consideration it a review of the UI data tecomes necessary at a later date.
- 3. In AR-j.tmig (MAMillAllull AND Sutf Aff Rt504U11011 Smnutt,eam ettensation la any material follows a decaying curve (expo-mential f usiction) Imwever, la some cases the reflection free the nearest Ibis makes it tale is $ salter than the reflectlen from a f arther liole.
difficult to draw a proper BAC curve. 14 such cases, it may be destralsle to esse a lower f reiluency or a smaller transducer for flaw detectica near the beam entry surf ace la overcome thee dif ficulty of marginal detectability.
h an-field effects, decay llae of pulse reflectlans, shaduw effects, '
restricted utess, amid ett.or futers do not permit ef fective emaelnatloa of certain volume areas in the component. le present a clear discumenta-tion and second of the volume of material that has sat been ef fectively ,
exaelned, these volisse areas need to be identified. Recommendatloas are 5 . paavided to best estimate the volume in the reglen et laterest that lias uut lieen effectively cammined, such as volumes of material near e x h surfue (because of Iear-lield effects of the transducer and ring-down effects of ti.e gnalse due to the cositect surf ue), volumes near interf ues between cladding and pasent metal, asul volumes shadowed by laalnar flaws.
- 4. lit Mt 121 f ti It fielps Beam piut tle is one of the sala characteristics of a transducer.
to slauw the thsee-dimensional distribution of beam strength for comparing sesults t,etween examinations and else for charuterizing flaws. 1he beam 8 profile sweds to be determined anal recorded so (list comparisosis say fee sa4 sis
/ 4 witti sesults ut sus.cessive examinatlocs.
~
l .
n' L F
- f - - ~ ~ . . - . .. ..
.w--
' L
- 5. SCAsselW. WI10 Ht I AL laillitt ACE li.e mamunt of enesgy reflected buk f ree a flaw is depesulent on its surfu e charu teilstics, orientation, and slae, the present A5ML Code prece-dures sely on the amplitude of the reflected signal as a leasts for judging flaws. this means that the slae estinallen of a defect depends on the proper-tien of the uitsasenic beam reflected back to ti.e prote. II.e reflection p Delete techavior of a planar delett, idiIch largely depends on the lacident beam
- angle whesa a single sea'cli unit is used to (bractertae the flaw, is thus ,
a decisive f utur la flew estleation. Ihe larger the slae of a planar defect, bean pattern, and hence
.the narrower is the seflected[Jisectional s 1,e f' law is amus e alif f itulL-to detect -and stae. Ilierefore, thee i.eam angles llI58RI It - for page a used to stan welds skuldh based on klee geometry of the weld / parent metal interfu e.
At least one of these angles sliould be such t h t the beam is ec sound beam a46es the flaw very dif ficult to almost perpendicular (185 degrees to the pespesulicular) to ti.e weld / parent detect in must cases (unless ties be88 489 I e la rightf.*I therefore, the bede metal intes late, unless it can be demonstrated that large (Code-unuteptatsle) angles used to scan snelds sliould be optieland and should planar flaws unf avus ably oriented, parallel to time weld metal laterfue, can l>e detected ly the ut technique IHilag used. In vessel construction, some Delete.
ueld pseps ne essentially at right angles to time metal surf ace. la thiese cases, use of sliear wave angles close to f5* 1s not recommended. Iwo futors 58d88sticleIWb2240 e sec ! a I of the A5Mt code, would make Lt.e use of shear wave angles close to 15* inadvisable -- first, the test distantes s.ecessary twcome too Igrge resulting in loss of signal " " " I Uhr*5 # F8 4es frem Surfaces. 8taines and langstua Central asul setend, the Generation of surf ace waves tenuis to confuse the interprete- I II 9e ating 8 ard, it.E. (Cf58) report ena&ner 110 Ig/Nilth.
tion of sesults. la these cases, use of alternative voltmetric moeulestruc Live examination (talt ) teckiques. _IttedOhe ASME CAJ should be considese4. Altesnative lebt tecluilques to lie considered may include high-intensity radiugs aph or tasales prol,e ultrasonic examinatloa of tlie welJ metal interface. la avoid the possibility of missing large flaws, particularly those 11:41 have an suitavarainte orientation, it is desiralste tisat tlee batit l
seilection ampillude, while scenalng with a straight beam, las monittred over I
briol> ability of Detecting Planar Defects in 14eavy Wall Welds by Ultrasonic f.
' lettailgues Auoiding to f alsting Codes.* Gr. Ing. Ilans-Jurgen heyer, ,
quality Depas taent of M. A.It. , Istirnberg, O e500 alured. erg 115.
t .
~
j 8 l
l . - . . . . . . . . . .. .
.s
W k
gl.e entise vol me of the weld and adjacent base metal. Amy area wtaese a .
reJiactiose et the seesmal back surf ue reflectica amplitude exceeds $111 stwald be esamincil1.y muste i.eams la lacraments of *15 eWjees neitil the reduction
, at siput is emplained. Where this additlanal magte 6.eam esaminaties is met peutital, it any 1.e aJvisable to consider eamalalog itse welJ Iny a supplementsey volumetric IG tuhalque.
- 6. SillE
! Ihe depth or throingle-wall dimensten of flaws is sure sigalficant than Delete the les.gth dimenstam, 4(cerding to fracture mechalts analysis criteria.
u>ing ti.e single prut.e pulse echo techalque, it is possible, depen.fing om '
flam e.tlentation il L semeMlarge flaws may met reflect ansch en[rgf 6 te ll.e seasth amait. A tecause al tatt possibility, the depth diseaslam el the timw slwuld B.eh'ceaservatively slied easitesIthde'vble'ac~e'li~- - IIelete prove (lat the flew erlentallen is at right angles to the beam. It is secumaended th4t indicatless that are assectated with threengh-thi(kaest I
flaws an.J ela nut meet Code' allowable criteria er criterla rectamended la this guide t.e sized at 201 DAC as well as at 501 DAC.
In tertain cases, it is possible for earlous reasoas that a flaw woesto not s et tett cau.cafi essergy to time searth annit to male the indicatlen height Stil I tie UAC curve laelylit. Itowever, if saach a flaw were large, a persist-eat sipal could I.e sJ tained over a large area. It is therefese re(eemended 15 41 all toutlausous signaals that are 20% of DAC with transducer travel move-neat et a.ese itan 1 lath plus the base spread (as defined la Article 4 susumasutalos y Appendix B, Settien V et ti.e Aild Code. ISH editima) skeslJ be (s asidesed siysificant and sl oeld I.e recorded and lavestigited furtlier.
the 1,ema speead etlect la some cases can snake very small flaws appear to be las ge i.hess jemkyd at 2t11 DAC- i ence, I,eam spread has to be cassidered la bakslauj time significance of flaws. It is thesesore secommended that maly signals witti a total transchacer travel aoweecat greater (ba the 1,eam spread slwuld lee tesesidered siga!ficaat.
I Ultras ult inamination Casparissa of Indication asut Actual flaw in RFV
- Isht ta.ajima-llarina laadustries Co., Ltd., January 1976. ,
.- 3 w e e
- .__ _ _ . -__.u_ _
~
i i
t stroallssG of itE50tI5 ;-- Ibis guWe gives recommendatiens ter recordlang the clearacteristics et the -
-WI examinettom systes. Ikis laternatten can he of significance in later analysis peceeds pertalaisig to 91 examinellens should be considered samality for deteralaing the locatles, dimenstems, erlentatten, and geewth rate of flaws, assurance s eterds. Receema4ttens en the collectien, storage, asul mala-tename of these records are given la Regulatory Gielde 1.00. *Cellecties, as referenced in the Safety Analysis Report ( and its aumendment Storege, as.d Nintenance of Iluclear Feuer Plant d>sality Assurance Secords..
Availatellity of these records at a later date will pesnit a review of the Delete Ul tesults fece the data gathered during prevleus saltrasonic emaalnatleas.
When ultrasonic emanimaties is perferend, certain volumes of material,
_- such as the following are an.L effectively emaeleed; such as material volume near each sistfac or valimes sP " by part y geometey, are nat_ gitectively examined. he velines of material that are
- a. hterial velene meer the fremt surface because of near-field oflects,' y
~ not elf ettively enemined depend on the particular part geometry and isolipse ~ '
claddfas distessbance, or electronic geting.
situations associated with each reacter pressure vessel. During identifica-tion of the material volumes that have met been en mined, consideration
. h. ' b terial velisme meer the surface because of sierfu e r @ ss w si.uuld t.e given to time types of flaws that are curren'tly belag reported in unfavoralite flaw erleatattens, scoe of tie operattug plants. these incliede stresa corresten cracks in the heat-af f etted sene, f atigue cracks, and cracts that are close to the sistf ace
- c. Velimes <hM by insestaties or part geometry.
~ asul sometimes penetrate the sierface. ihese velimes of material should be ,
Identified asul reported to IEC along with thq report of welding and material defects in uterdaue witti the recommesulation of regislatory pasilien 2.a(3) la some cases as such as I loch (25.4 mm) er more belans time surf u is met emaaland becaisse of the electrealc gate settlag. . Ilits means that time of stegulatory Guide 1.16, "Reportisig of Operating Information--Appeam!!n A ennemanteed veline any cantala flaws that weield be asnacceptable acending to lecluiltal Specifications.=
Sectlee kl AM Code, as fellows:
C. RtGut A100tv P05tl1010
- a. tiltheast evalasallen (deeper than apprealaately 0.2 leech)
- h. Even af ter evalisatism (deeper these appreminately S.e5 leich) '
Ultrasonic emaninatten of reacter vessel welds should be perf &med ucordis.f to ti.e respairements of Sectlen El of tlie A M R&PV Code, supple-Assianing an aspect ratie of 4.1, accordlag to Ilm- 3616.1 Sectioni ut, AM Code, neated by the fellowing:
flaws 0.2 laches deep woestd be isnacceptable for a S lack well thictness.
- 1. psykteuMI Pikf oteWuett CittClis i
.. _ lypically a SWR reacter pressesre vessel (SPV) well la the beltline reglen Ilw cliects descrlhed in paragraphs 1.1 threisgli 1.4 should lee is 6 laches thick and a FIA-RPV well is 8.5 laches thick. During flaw esalue-ende for any UI system used for the recording and slalog of reflectors la tien, sdnere the wall temperatiere is hids ased the available te>ugtress is high, uterdance witis aegislatory positteen 6 asul for reflectors that emceed time and the calculated critical sestf ace flew depth (a ) enceeds the wall thictness
~
Delete i g g, -_
_ _ _ _ _ _ _ _ _ . - _ ~ , . _ _ - . - . - _ _ ._ .- - - --~ - ~, -
. - _ , . - _ _ ~ ~ .-. _ . _ _ - - -. _ . , . - _ , __
e I
Inseri Caettained (L),a gis lateak as t h well thickness. Accordlag to 1W-%40, Section'XI, flaws exceedlag this alleueble the allawable end-of-Iffe site is ag = 8.lag .
value, which would Lee 9.65 lack for a F W and 9.65 lath for a SMt. will leve to be repaired, the at.ove emaaple Illustrates the h rtam e of blanting out the electrealc ladication signals and met omaalains tlie surf ke volume te depth of one lack. Since the flaus that can be alssed becaense of electaw lc gating say be larger thart the flaws pesmitted with or without evaluation, this unemanin=J welume la lavortant and needs to be identitled.
, la certain cases areas were ant examined because lasulattee was in tl.e f' way and the transducer could not scan the volume of laterest amJ MAC was never apprised of this situallen until ansch later. In view of the above and to avelJ licensing delays, it is advisible that the welimme of areas met emanined far any or all of the above reaseas be reported.
- i. t.
I L 1
L .
l' age 10.
A5ME Section Il-LPal, MP-MS-5A, special repos t
'#. Flaw Evaluatlea Procedures: 9 Ansgust 1978.
.J s s
~
Code-ellauable criterla As a alais m , these checks should be serlile or ' % ulthla one day asut[f ter eamalalag all the velds that nee.1 la be examined la e reaclefN - ulthla one day prsssure vessel ehulag one eutage. -
Pulse shape and malse suppression centrols should reunala at the same
- 1. I Screen llelgt.t,IlaearIty Screen belgt.t linearity of the unitascalc tastrsament shoasta be deterstaed accardlag to tim saudatory Appendia I to Article 4, Sectica V of the ASMf Code, f ultble the ilme limits gpegggled ga C.R.
uith the same setting of pulse shape modificatloa and aalse typressies controls O*I*E*
as assed during esamination and to the same range of the lastrsament as the range that uoistd attually t,e used shartag exaalaalloa. for systees uslag an electrealc 8AC, a means should be devised and used for demonstrattag the proportleaality a,f the signal respouse to dif ferent sizes of eeflectors at 1/4,1/2, and 3/4 I depth. the accusaty of the propertionality shoisld be recorded. _
._.~___..
^
~ _ _ _ _ _ _ _ . _ _ .
I.2 AmpiltaSe Control lla.earity Amplitude control linearity siould Ise deteralmed according to Llee aanda- ~
tesy Aste sla ll ef Article 4, Settloa Y of the A5ME Code, 1971 editlem 4 #~ g
___ .. I
- l. ) Legacyhtitiale Curve Delete A photogragdilc seterd of the frequency-amplitude curve should be statained; lhis i as a mialaum, ut ee a cesera is anot available, the peak f requency value asul pelat A gdiotographic receirJ e,f the frequea(y-amplitude curve slaoislJ I,e idet* led.
( 3 A 6 do, aset 12 gl.elou peak frequency amplitude should be recorded. urd sluuld I,e avallatele for compartsue at the laspection site for ti.e meat two senessive refletter used la genwsatlag ti.e frequency amplitude curves as well as the elec- laspettleas of tie same volume.
tsoulc system (i.e. , the basic neltrassaic tastrument, gating, form of gated sigual, and spea tsise analysis equlgeant) and hou it is used to capture the y Delete (seqorsay .aplitude internat tom sinould be do(innesited.
I
- 1. 4 Pulse St ge g,4 pulse shape l A pliutogras4 lc s etand of ti.e unloaded lattlat pulse sineisld be statained A photographic record of the asalead.J lattlal pulse agatast a cat turated h W sgalast a calibrated tiee base. the time base and'woltage values shoestd si.oulJ 1,e obtained. ll.e flee base and voltage values shuisld 4,- ,,
- - g
2.1 Callbretta. for llammal Scanales be identified arul ru arded en the hortaantal and wettical amis of the above I f or samiset scanalag for the slalag of flaws, static callieration may be photogras.htc secord of the lattial pulse. the method used la obtaining used if slalag is performed uslag a static transAscer. lanen slynals ase maal-the pulsefst'. ape phtegraph, including the test point at utilch it is obtained, elred during calibration, they should alte he mentelted eherlag slaims. for skuld be dxuncated. mesmaal scanalag for the detectles of flaws, reference hele detection skuld be slumns at scanalme speed and detectlea level set accordteigly (tram time dynaalc
- 2. cat 18ttAlfose r SAC).
System calibratten skuld be checked te verify the SAC caerve asmi the -
2.2 Callt ratten for llechantaed Scanales sweep range calibration per massmandatary Appcmdia B. Article 4,Section V h flaw detectlen and slalag are to be abasse by mechaalnd eipsipment ,
of ti,e ASHL Code, as a slalenas, betere and af ter each reuter pressiere vessel the calibratten should be perfereed insing the fellowlseg guidelines:
emaninattua (or euh week in which it Is in use, ishichever is less) er each a. Calibratten speed sheenld be at er higher linen the scesialag speed.
' time any component (e.g., transehacer, cable, ceanector, pulser, or receiver) b. Ilie dire (tloa of transabscer anwenant sharlag callbsation st.uuld k la ti.e enaminatinas system is changed lonere possible, the same calibration the same as line directica sharlag scamalang asalass (1) it can W shawa thL the blu t simuld be used for sisccesslwe laaervice em'aminatleas af Llie same reactorl -
change la scanalag directlea does met make a dif feresica la the sensitivity and pressure vessel. the calibration side holes la the basic calibratlea ble(k
' wH.rattaa liac6 ground messe received f rem the search esatt er (2) atteinatively samt the block surf ue should be protected se that their characteristks de these dif ferences are taken late accesset by a correctice f acter, not cl.ange during storage. Iliese side lioles or the block surface shoesid c. f or anchantaed scanales, signals should set i.e maaletted ilurtsig the not t.e dified la any way (e.g., by pelishing) between sisccessive emanina. establishment of the BAC curve.
Lions. 18 these (allbrallen reflector holes er tiie bla k seerface is polished d. One of the fellowing alternettwo guidelines should be failuwed far t by any chemical er me(hanical means, this fact should be recerated. establishlag the SAC curwe:
- "8 * * ' " "
3' let AR-5tml Att IXAMINAllelt Aldt SHBf ACE Sf 50tull0lf
'- mounted on the mechaelse the tellt he essed for eaaalaation of the cuegenent.
(2) Correction futers betueen dynamic and static resposise should Ihe cap.bility to etlectively detect defects near the front azul bug lie established estag full-scale neckieps.
surf ues of the actual componeet should be estlasted. Ibe results should (3) Correctlen facters shoeild be established uslag models asal tak-be reported with the repost et abneraal degradation of reactor pressure lag scallang f actors late censideretten (essumed scallag relattenship sliould be 6taulary in ucesdance ultia the receamecdallen of regulatory position 2.a(3) ilII'dI-of Regislatory Guide 1.16. "Reportis.is of Operattag In8ernatiam--Appendia A (4) Correctlen facters between atynamic and static response $8.ould I le( h ical specificatiuos." In detesalalag this capel.llity, the ef fect og be establistied free the ladications that are fessad stierlag examinatiusi for slalag.
the followin.: tutors shauld she lee unsidered; f or eletection et flaws aberlag the lattial scan, correction tutors may be assismed
! a. 18 an electionic gate is eased, the time of start and stop of the- based en englaeering jesegment. If assumed correctlen f ar. tors ase assed ter detec-cont r ol B.alats of the electronic gate s!.ould be selated to the valisme of Llen, timese f actors should later le confissed en ladicatlous f rom flaws in th
. material sear eacle surf ace Lbt is smet being evenined. t h
I ( 12 i i
-- --- e.. _., . . . ..%..
=
- Sh
---___.____-_-_---_-_---A - M wi e- & .maV m
M s"e *'c-e - a-- %__ -__----__.e-1-----.2:n.- - - -
N lasert Comtlaued 6
wessel during the examlaatloa. Deviatless from the assimed value may styJest reemanlalag the data.
2.3 Calthratlea CI.eds If an 185 is used for calibratloa check, the fellouing should atyly:
a_ the sigstf tcant DAC percentage level used for si.e detection ased stal%
of ladications should be reduced to take late accouant the maalaum error that could be latroduced in the system by the warlatten of resistance er leakage la the casuwctors or other causes.
- b. Calibrattoet checks should be perfassed en the complete canuwcted system (e.g., transducer and cables shoeste not be checked svaretely).
- c. Measures should be taken to ensure that the dlftarent verlebles sue.h as temperature, vibratloo, ased shocit lletts for uhtch the 155 error band is determined are not exceeded eksrise transport, esse, and starage, etc.
- d. When a universal calibration block la used and some er all at the reference holes are larger than time reflector holes at comparable depths recommended by Article IV,Section V, of the A$lt Code, a correction f atter should be used to adjust LLe DAC level to compensate for the lasger r="
holes. Also, if the seacter pressure vessel has been examined before t-f uslug a conventional talock, a ratio i> atween the DAC curves obtained f rom tlw two blocks should be swted (for refesente) ulth the significant Ismilcations data.
Page 12.
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'A
- l. . the du ay time, la teros of metal path distance, of the taltlat pulse and of the pulse reflectless at the front and buk surfue simuld be tensidered
- c. the distusbance created by the clad weld metal interf ace with .
the parent metal at the front er the b u k surfu e should te related to the
. volemme of matertal near the Interfue that is not being emanimed.
- d. the distuabance created by front and buk metal surface rougtusess stwuld be selatgd to the volume of material near euk surf ace that is snut belag emanined.
- 4. BtAH PkOfill II.e beam peofile should be determined if any recordable flaws are detected. Ibis should be done for euh searcia unit used during ti.e examina-laterpolation may be used to obtala beam profile correction, to assess tion by a pianedure similar to that outilsseti in time nosmandatory Appesutin B (8-60), Article 4, Sectiosa W el the A5HL Code, for determining ican spread. flaws at latermediate depths for winich the beam profile has put been Beam profile (us ves simuld be determined for euk of the holes la the basic determined calibration blod.
S. ifAletlE talD-MtIAL INILRf Att Dette lhe beam arujles used to scan welds should t.e based on time geometry of the weld / pat ent;*etal laterf ue. At least anne of Lliese angles shoold be isnievourably orlemted Pl anar flaws such -a the beam is almost perpendkular (115 degrees to the perpenalicular) to the weld /seasent-metal 1 iterf ace assiless it caen t e dimonstrate.t tinat large 6 _
pfode-unaneptable)planarflawsinnfavorablyerlented,paralleltotheweld, i
{ metal intel acjcasi tee detecte=1 t y time til teclianittue laelng used. Ottierwise, use of atteinative volumetric nondestructive examination (leist) te(luilques, as pesmitted by the ASME fede, should be considered. Alternative GR)f tech-salapses may be tunsidesed to include higtr tutensity radiography er tandem piobe 1)elete ult as sila einamissatiese at the welMlp letterf ace.f Beinig~kes used d'[
I alt emaaination simuld t e sepos ted wilia the report of abnormal degradatiosa of reacte>r ps essure t oueuLary in accordana.e with the re(camendation of regu , ,
latory positio:a 2.a()) of Regulatory bl.le 1.86. ;
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- 6. Il[l_%
- ledications fium geometric sources need not be recorded.
6.1 Irevellsg leidications tsulicattens that travel en the horizontal basellae of the scope for a distance greater than indications f rom the calibratten I. ales (at 2GE ampil-tude) should be unusded. leadications that travel should be recorded eed sized at 201 DAC. Whese the Indicatlea la slaed at 20% DAC this slaa may A be cua retted by sidstractlag for the beam width,in the threesgle-thickness - ~ - - . . . . _ . . - _ _
disection ut.talswd f rom the calibration hele (between 201 DAC potats) that is at a deptia similar to the flew depth. If the ludicatten exceeds SSE 6AC, the size should f.e recorded by measurlap the distasico between SOE DAC levels wittunut uslaug time beam width correctlea lhe determined slaa should be the las ger of the two.
6.2 Huntravelbigladlcations hts aveling indications above 2e5 SAC level that persist for a scanning dlstanne of more than I inch plus the tieas spread Teetween 201 BAC peints e
(as defiened lay tlh nosmanidatory Appendia S. Article 4. Sectlen V of the ASMt tede, 19f f edition) sliould be considered significant. leie size of it.ese ilaws should be determined by measiering the dlstance between points at 501 DAC anul betweus points at 20112C where the f.eam-width carrection is made ent; for the 201 DAC size. lhe recorded slae of the flaw weesid be '
.tlie lasges of the two determinations.
II.e fullowing luformation should also be recorded for Indications that gelete ase sepos table according to this regislatory positlem:
- a. Indicat tens should be recorded at scan inter.als no greater ti an one-teurth of an lente.
I b. the secosded luf ormation should include the indication travel I (metal patti Irnuth) asul the transdiscer posillon for IDE, 20E, 501. and 5001 DAC and ti.e maximia aeplitude of the slysal.
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a_______-________~___-_. _ _ _ _ _ _ ~= -- -- - - - - - - - ~ - - - - - . ~ - _ -
- 7. RSPORIING Of St Sul15 Records obtained while following the recommendations of regulatory positions 1.1, 3, 5, and 6, we along with discussions and emplanations, g gg,gg if any, si.ould inhgiotteell tWWralRatteDnest resisi i NP NI
- the size of an indication, as statermined la regulatory positleas 6.1 or 5.2, ,
equals er exceeds the allowable limits of Section Il of the A51( S&PV Code, y Delete the Indicallons should be reported as abnormal degra.tation of reacter pressure 1,ouwlary in au erdance ulth the recommendations of regulatory pasillen 2.a(3) of Regulatory Guide 1.16. _ Delete Atoms wills ti.e report of asttrasealc eaamination test results, the follotr-
"ing intasmation sleuuld aise be lacluded: Ilie best estimate af the portlam of the veline sagstred to be
- a. the best estimate of the error band la sizing the flaws and the examined I.y the AstE Code that has mot been effectively emantned basis for this estimate should be glwen.
- b. )theLesteitimaIDI'lWwelumethathasnotbeeneffectively J Quained out of the voluna required to be emanined by the A5it'i Code such as weltmes of materid near each surface becau.e of r. ear-field or other elsects, votimes near laterfaces between cladding and pareet metal, volumes shadowed by laminar material defects, volumes shadowed lay part geometry, voltanes inaccessible to flee transducer, welumes af fected by electronic gating, and volumes near the surface opposite to the transducer should be glwen. _ _ _ _ . _ _
Delete
- c. litconsidered_dn material volume that has not beca effectively emanined by the use of Lie above precedures may be examined by alternative ef f ective volumetric N0t tecluilques. If one of these al,ternatlwa leDE tecluniques is a variation of til, recommendations of regulatory post-tions I and 3 st. auld apply. A description of the techniques used should be included to the seport. If other volumetric techniques or warlations of ul are used as imilcated la regulatory position 5, the ef fectiveness of Lliese techniques should be demonstrated azul the procedures reported for review by the NRC staff.
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Dels-te D. IMPL D ietlAllost f acept in tlasse cases la which an applicant proposes an aceptable alternattwe b It.ls psopose.1 guide has been released to encourage paetic participe- sethud for cumplying witti specified portions of ties Cummission's regulations, tien la its develugment. Encept la these cases la wealth an applicant pro- the method descrlied *.e herein will be used la the evaluatloa of (1) ti.e sesults of insesvice examlaation programs of all operatisag reacters asal (2) tl.e eesults poses an uteptable alternative method for complying with specified partleas
_of the Camelssleet's regulatlans, ti.e method to be descalbed la the active of preservice enamtmation programs of a'st reacters usader cosistructlen pertosmed after July 15, 1981.*
guide seilecting pselic ceaments will be assed la the evalasation of (1) the results of laservite emaalaation progrm of all operettag reacters performed t Elia retwoulattens of this guide are seat latended to apply <a paesenwice enamtmations Lliat have already tieen cumpleted.
after issuante of al uttwo guide and (2) tl.a results et preservice emaalas-the leRC staf f latends to reccomend that all licenseas modify tieelr testamical tien psograms of all reacters assader construction perf ormed 6 months af ter specifications so tl.at they are coasistent with the reccane alatleas contali.eil Issaente of the utive guide.
the recomeemtatios.s of this guida are not latended to apply to pre- k betala.
,I service enaalmations that have already been completed.
Af ter the issuance of 0 e active gulde, tiae hRC staff latends to
- latended to be 6 muntlas af ter the issuance of the yelde.
ruemeesul ttut all licensees camside- modifying their tectunical specifica-( tiens so that Lt.ey die coaststent with the receamendations contain=d therela.
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[B I rAthE/IstPACT 514If MElel - ,
i
- 1. PROF 051D ACIlott i
1.a pescript M .
the present laservice sammlaatles precedures for nitrasonic examluatloa "r presant laseEstceemantmatleaaltresealctestlastul)precedures '
require leprovement la order to coasistently and reliably charactertre flaus for flaw de'ectise reqastre laprovement la eraser to comaistently and reliably
,.9 in reacter pressure vessel (NT) welds and SPV assale melds. lhe apparent low-character 6se flaws la the current reactor pressure vessel (RFVI welds and f EPV noaale welds. Ihe apparent law level of the repro.hacibility of detectles.
flaws leads to lengthy discussions and delays la the licanslagt paucess. Gseat locattom, asul characterisation of fleus leads to lengthy discussions and attentlea is paid to the lategrity of APW welds during the licensisga prosess :
delay la the licenslag process. Great attention is paid to the instegrity because the fallisse probability of a reacter pressure vessel is considered to of kPW welds durlag the licenslag process becaus6 the failure probability be suf ficiently low to encisada it from censideration as a design basis accident.-
et a reactor psessure weasel is censidered to be sufficiently law to euclesde e the assumetton of a law probability telles heavily en regularly seg.eated it from consideratis.a as a design besla accident. 1he ratlemale for this laservice esmalaatles by ultrassaic testlag of welds.
low psebel.llity relles heavily en regularly repeated laservice emaalaation by ultrasoutc testing of welds _ _ , -
' ,A_
- 1. 2 Need for Proposed Actlam As more reactors start produclag M r. as these in aparatlea grow la age, and as more lesservice enamtmatless are performed, the number of detected
- flaws with untertata characteristics (slas, erleatatloa, and location) is '
likely to lacrease. Ilaw characterizatlea is essential for ;Iaw avaluattens t quiredt>ytheASMECodeandbyllRC,todeterminethestructurai lategrity of nuclear reactor components when sesch flaws exist. Et is essential to 1. ave valid bac6 ground data for the flaw avaluations registred by Sectica El of ttw A"'t Code. Based en the informatlos gatleered accorating to A58E Code requirements, it is atten dif ficult te assess weiether er met Lt.e flaw has usewn betweese exaaleatlans. Ihe procedures now la use ele not require Lt e recordlag of (artala late-sallen that can be important la later analysis 4 #
11
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for detesalalag the locatten, dlaanslems, erleatatten, and growth rate of flaws.
Ihe lack of standardtaatlea la the ase of 188 empsipment and precedures leads to uncertalaty las h results obtalmed. fee emample, transducer charac-
=
teristics sect. as t,ean spread, d.mylng characteristics, and fresyssacy for amieie
,la.d. and Wre is . ,, is t Le ,e., tru .f
- ,..L r.s a. e,. m t -
these from one esamtmattaa to the e h r. Similarly, characteristics of other WI system campements such as padser, receiver, emplifier, and widea display screen may vary frem one amenlaatlea to amether, and all these charec- la many lastances, the rate et flaw growth can te even ante leportant than teristica can lefluence the magalteads of the flew ladications. therefore, the flaw size, for emaaple, if a flew is femme la en m i amarle er lealt line wels-defleed criteria for supplementary UI precedures ua meedeel se that regles and it can be dessestrated without deed >L ht the flaw allt nut grear it '=llt f.e pess sbie to characterise flees correctly, estimate flew growth, and has met been growlmg, a rather large flaw can be tolerated. Crack initta-and have reprodu6tble results free laspections perferned at different tlans ti6e and growth is also a potential prehlen la e ases ashore it is probble ht me crack esists, best tenere hre is a cluster of small rounded iscluslaus.
using different equi.nent. l
' 'la many lustances, the rate et flaw grauth can be even more tapertaat i these clanster of laclustems should be mentternal by ist to ensasse abseme of cruks" them N flaw stae. f or enemple, if a fleer is found in an apV netale er and cruit growtli.
belt Ilme regina and it can be demonstrated without doubt that the flame he h rate et flaw greuth is entwted a.e be large er is amatertain, will not grow amt has me.1 been growlag, a rather large flaw can be taleratet even a small flaw may 1.e of cance:w. le permit determinattaa of grauth rate, lhls is also a potential prehlen for cases ednere it is probable that no LA* UI P'*C**** Shl4 be such ht results of saaccessive ill emaatnations trad exist:, t.ut %ese is a cluster of small round.d lactustoms that maest '** I'e cespared. With preseet precahes, these resentis cannet be compared be asalte. red by flaw groneth technistanes te easeste acceptable behawler. becaense of warlatten la lastressent system characteristics. UI lastrument systen t=L If 18.e rate of flaw growth le espected to be large er is amicertain, Characteristics depend en the characteristics of b systems dif ferent cualmanents, even a small flew may be of cancera. For cesparlsen of resesits to deter. Verlatten la h tharacterlatics of Calibratlea lbleths can also affect results.
eine growth rate, tl.e UI precedures sineeld be such ht restants cf succes- Gesidelines are needed se ht uncertelatles la flaw charactertiettua may sive UI ennaluations can f.e campared and flaw gree th deternlmed. With present be reduced er ellelmated, Safety of the coupesments is evaluated by the i.elp proceduras, taese resesits cannot be campared because of warlatlea la lastru. et fracteare mechaalcs. flaw slaes amed to be kanssa for' fractawe ne(0. ant (s meat characteristics. UI lastrissent characteristics depend om W character- avalesatlens. Uncertain determinaties of flaw slaes leads to intcertaisilles la latics of the instrument's dif f erent campenents, and verlatten la the charm. me dr*4minellen of W safety of W components. thacertaintles la cualwees.t teetstics of calibrettom blocks can also af fect rosestts. safety lead to delays la liceaslag. linere is a mead _to specif y am4 steamlardize Guidelines es e see=ded se that assicertalattes in W fle s characterisettom the performance reepaired of aust UI symtem compements to ubleve I.etter (ese-and sesulting delays in h licensisig process may be reduced. There le a sisteary in UI results se that delays la the licenslag process may 4 e reJiaced.
meed to specify and standardize re6 paired performanice of most UI system campe-*/ .s
- 1 L sients to achieve better coasistency la UI results.
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- - - ~ -
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3- - _ - _ _ . - _ _ . - - . _ . _ _ _ _ . _ _ _ _ _ _ . _ _ _
Ihis proposed guide will provide swpleasentary proceeares estth the objective of leprowleg conventlemal UI prece& ares, as defined la the B&PW tode. Ikts relde is based partially en the laternation available la liter-ature on I,etta U.S. and f ur6 pean prece& ares and partly en the jsadgment et the takC staf f and their consultants. Sa the basis of support eserk being Delete performed at the Oak Ridge IIstional laboratory, the staf f plans to issue a revislum to this gulde that should faarther leprave flew r.haracterlaatloa.
the use of saew tachalapses sesch es belegraphy or synthetic.,apjo ture __.
laaging of flaws by Ul/~t1Ich have not Deeri introducahe practice and could c side,.i.i , lac,e.se t e cost of ins.,, ice o.ani Liogra mot eing ,,e-
,esed ~ ,..
1.3 Value/leegt of Proposed Action Delete h3 I M. - - - - . . .
Reporting of UI esamination results as ladicated la thls guide tsould Beporting of Uf esaminellen results as ladicated la this guide woulJ belp help the takt staff asut their consieltants to better assess Elie results of I Line IIRC staf f and their cessaltants to better assess the results of the data.
the date. talkC staf f time for review of reported date and laterpretatloa At present, a great deal of time has to be devoted by the tillC staf f I cause of of indicatlans is likely to be reduced. _
- ~
the back and forth arguments and controversy over detesnlaing ti.e saf ety of components from laconsistent Ul results. Lack of faltls la flaw stae deteiml-1.3.2 Ott_.er Gewersment Agencies sallon from uncertain UI results pole *. toward the aduption of some tenserva-h t applicable, unless the goverannat agency is sa appitcaat, such as tive safety measures that are mostly undesirable to the ladustry managers.
gy3, Licensing delays occur t.ecause decisions have to be taken on the leasts of
- uncertala Information. flait size detesvlaallon f ree coaststent Ul sesults 1.3 ) Imlustry would help semove or reduce the imetertainties ased debates on lle saf ety issues.
the value/lepact en ladustry of the proposed regulatory guide positions Because of the al,ove, IIItC staf f tiene for review of reported data and latespreta-Is stated I,y each ;asitten la the appendia to this value/fepact statement.
Lion of Indications is likely La be reduced.
Some highlights of ttw value and Ingsact of the proposed regulatory Guide positions ese stated below.
eL_M e'e ,
l.3.3.1 value. the proposed regulatory guide s a sci.c. 4 milestone]
(in the tect.nical activity of Task A-14 as defined I,[y faita andh t:.sfies supple- _
seestary pan (edures that will lead to the following advantages:
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' 19 s
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9
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- a. Attaining greater accurxy ased coaststency in flew characterisatten.
- b. Providisag informatten for coaststent flaw characteriaatten at 84kC review time and thus reducing IIAC staf f ef fort la review of flaw ladicatleas.
- c. tielping assess flaw growth.
- d. Providlang a more reliable basis for flaw detecties end evaluatloa,' ' ' ' '
- IN 8'"Id*"'"
whicf, should help in the isnifesa enforcement of rules es%' '
h~
delay in licensInT dTod sII.n E ~ ~
Delete
- e. Reduclig licensing time for reviewing en laatlea r results, which will aid la the reduction of reactor dews ime eksring emantmatleas asui will I.e of great benefit te ladustry. With present construc-tiene costs of about 1.3 billion abilers for a 1000 megawatt reactor arid the average slae of a reacter running ereund Il00-megawat capacity,thesavingsperdaybyellainattenofreacterdowsflee ase likely to I,e $500,000 er more.
- f. Avalding usinecessary repelrs alue to flaw size uncertaintfes.
- g. ke:ducinen radiatloa empaansre to persesueel by inelping to eliminate uswiecessasy rapairs. Ihe redlettese empossare sherlang repairs is usually many times the empesure during examismatloa, se a not reduc-tion la radiation espesure is expected.
I h. Reductog margins of error in estimates of flaw grouth and (laus hulping reduce everconservallwa estimates and dactslens on flaw au ept ance.
k n'. l. Providisig more constatent UI preceduses for flaw characterization, theseby leading to proceastes that ensure lower probability for 9
20
,~ t k
- - _ . . .._ - -.-_x. _ _ _ . - - - - . - . - - _ . - - . - - _ - _ _ _ - - - . - - - . . - > - - - -
.w.- -,n - e ,.,,- . , - . . --- - -. - - -- .---. --,-- . .- s._---- ----- -
misslug lesge flaws and enseerlag greater safety for the piellc.
Ind.sstrial wurbers, and goversament employees.
DeIete.
1.3.1.2 lar _u L . there will be major lepast la Llie following three areas:
- a. blyy Sout_rel of the UI eestament
- At present, registremen's in the AMIE Code for quellty constrel of UI equipmeM ase masginal; for example, tlnere are no direct ragsfre-ments to aontrol the quellty of Ul tran6ducers. Criterlen Mll.
" Conte el of Iteasuelag and Iest Esgulpment." of Appesultz 8. " Quality Assura.we Criterte fe= leuclear Fower Plants and fuel Ferrocessing Plant s," to 10 CIR Part 50 rosystres, in part, that measures be estaallslied to ensure that insisuneesta essed 's activill+e af fect-Ing quality are yirsperly controlled, calibreted, and adjusted at spe(if:44 periods to malateln accastacy within me.essary limits.
the s ecommenal4ttons of this guide nellt thelp to bring about uniform-ity in the quality centrol procedures among elfferent companies and will ensure that gesality control measures are taken to ensure sellebility esul reprodiscibility of Uf results. Bio new UI equipment will be needed to follow the recommendations of this guide. flowerer, ts.e quality control measures recommesuied for Uf equipment will impose e tra cost beardens that are difficult to estimate without f eeau,nu isua ladustry.
- b. Incseamin examination time lhls guide would recommend, for time first time, that indications with sigullicant length of Swaltation travel (larger than the stasusand calibration holes) er with significant depth dleensions be s econ ded. It is swt expected that the slag type of flaws, Walth as e common among welds, or geometric reflectors will give significant traveling Indications within tla guidellses proposed.
'lleene, nu substantial increase in recorded Indications as a result of this retommendation is s,apected; however, the erect f ascrease is difficult to predict er estimate.
a
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I Rel.ortis*G of Italicattees assecleted with flows larger thaa 1, lack ,
(Indicationa larger than & lach plies beam spread at 20E SAC level) is also new. RPV welds are amaatned by redlegsrphy, anel es flaws larger lleen thsee eysarters of est inch are accepte6te le these welds. Recause of this acceptma.ca length, only snew service-indieced flaws lasser than 1 lach, of %$ch there alieuld not be many, are eng.ected to be plcked esp and raperted a6 e result of thls ret eesesulat len Because of the abewe tw(. new reportlag receaseendatleas there may be an increase In examinattee (fee and deltar cost that is ditficult to estimate. Ihle will depend on how masty significant flaws are detected and how lasse anJ comptem 489 are.
- c. Nadiatten emposuri kecommesulattens of this gealde apply to the'ementenatlea of RPV welds and RPW assale welds. ApW welds are usually emantned by autumated equalpernt, and data are cellected en tape. Therefore, ,
. no increase la radiatten exposure is anticipated as a result of tle segulatory guide posittens addressing RPV weld enselaations.
i kPV waale welds are sometimes examined by automated equipment but la most cases by manual ul. Ae increase in radiatten empesure ;
i to emaninatlose personnel may be expected while RPV megales are being manually emantned. The probable percent Increase la emanlaa- _
tlem slee or radiatlea exposure is Impossittle to estimate without field data and research effort. Registrements for reporting travel-Eng leniticattens aspe is.:'.icatless assectated with flaws Ierger than
! inch may leaJ to an lacrease in occupattesial espesure la these cases in which the abewe Indicatleas are found and additlenal examinatiosi is required. the magnitude of this addittepal empesure can only be assessed on a case-by-case basis. It steutd Ise meted ta.at radiatten levels at vessel nerale reglens are reported to 4
22 e ==
=ueme M splu. empee gh 9
.-____m_- _ _ __ _ _ _ _ _ _ _ . - _ _ . __ mm e m =-sre=---- . tav-vu mee v. = m em-e=siu vsi- a eu_- + e- me- m- t -- _ ese.- aneaeaww asweg-.=-, --e-st, a w.m m a s.a ms_._._-m__.mA__m___.
- , d I ran.je fruss 0.5 to 2.0 res/ hour. Total mass-rom doses can be drastically reduced by shielding and local decentaattaatloa.
Ike guide la sust expected te Inave any adverse impact on other goverrusent agencies os ti.e public.
- 1. 3. 4 Putallc_
too lep4(t en ts.e paelic can be foreseen. The saly identifiable value is a singht aucteeetion in the review process.
1.4 Decis ten ein Premosed Actlest
~
lha nialsten-.O r,: ;;i'-_ ; " _ _ 8eRRyas state.1 tl.a need for this guide to help them an:t their censultants 1.s evaluating the site and signif-Iconce of the flaws 46tected during inservice esaminatten to ensaste the Delete lategrity el seactor panssuee vessels between periods of emenlinallen. It t.llire,s...e.dvisietoissuethisp;l,es.dj,ui1,orcommente 8
- 2. AITROAft1 2.1 lecimical Alternatives Alternatives would include registring ttie asse of holography, synthetic apestune imagtsig, acoustic eelssion, neutron redlagraphy, or a combination of the above din ing ItPV laservice emaninallen.
2.2 Procedural Alternatives one alternative la to leave time situatten es it is. A second alter- '
native is to sgaest change of the A5M Code requirements. .
f .
b g 7
2.3 Compglson of lettinical Alternatives telwsing inservice emaninattom of ItPV welds by the sese of holography, synthetic apertuse laagisig techsilqise, or accesstic emissten, iAlch are still in 44 e stage of prototype development and ednich have sist been proved ef fective .
for field use, would met be justifiable em the basis of either test er ei f e4.t tveness.
- 2. 4 tusterison et Procedural Alternet(vy teaving time situation as is woeste seen that contissued attentlen and manpouer would have to be devoted by time leRC staf f to lavestigate the assicer-talaties associated witte fland growth en a case-by-case beste. Ilie loid level et confidente inthepensenttectaniqisesmeansthatexcesstwomargins(wNI ,
tt continue to be used in the flew ecceptante criteria. Alsegeinecessarycutting asul repair at teampts to remove suspected flaws may result. --
9 lhe pennedin'es recommended in this guido leave been shown to be effective la practice, alti.ouyte ti.ey are met le gesieral esse Isi time tdsatteel States.
Isecluding these pe utedures as regulatory guide recommesulattens should result Isa their wider use ased consequently their lapsevement. Af ter these prece-dures have beesa muepted by the ineoustry, we will seek their inclusion in the ASHf Code. Some of these procedures leave already beese sent to the .k$in for consideret ten and Isaclusion in time present A5MB Code precedures for ultsesonic eneminattens.
t 2.5 Dehlen on lettuilcal asul Proceaharat Alternatives on the twsts of the eteve, it appears desirehte to lasue a regulatory f Delete guide to.ps evida retuamendations for leproving AMIE Code precedures. these recuemmen-Jat tuns, whitin are based on tine advanced state-of-tine-art UI prece- '
ties ability to detect and clieracterire flaws willanut legansing new, unpsowed duresintursentuseleysomeo.rganlaations,wouldleprowelfleesdaiectahilliy-y and charettes1:4 tion without leposing eiew issyrewed tethulques for flew tachalgeses for flew detection on ladiestry.
de t et t ion oss indus t s y. ~
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. - . . - _ _ _ _- _ _ - _ _ - _ - - - -- - r s - a . _ _ - - - _
s I 3. 51 Alufo#Y CostsIDtRAlletts 3.1 teRC Authority this gulds m uld fell ander the authority anal safety requirements of tinreaisin the Casselssions regislations la Title 10 of the Code af federal Regula the Atomic Enerigy Act layarticular ander $54.55a " Codes and Stadrais --
of 10 CIR Part 50.htcthegastresp in part jthat strisctures, systems. and components be designed. fabricated, erected, constructed, tested. maJ laspe(ted to quellty standards commesasurate with the leportaaece of the safety fianctiva to 1.e performed. 4 3.2 iteed for idPA Assessment the psoposed action is not a u jer actlaa as defiand by le CfR 51.5(a)(10). asui does not regaalre an envireamental tapact statement.
Recaneendatloans of this guide woeste be supplemental to the requirements of Section XI. " Rules for Inservice laspectles of stuclear Feuer Plant Compo-
- ments." el the A5HC Code, uhtcli is adopted by 650.55a. " Codes and Standards."
et to CIR Part 50.
h
- 5. 'M etARY
^
leils 3. reposed guide was f altlated as a result of a request free kha Div Delete
}s[{U'l((h erallag Redc19r31 ItRR. [Wieres a part of Task A-14. as defined) -
by liRR, aiut is IdMiled as a sllestene la the tectualcal activity of Task,I
.. . -~
A-11
/ Ps ellaistasy sessalts of ti.e round rabia 48 examinatteen precedus es felleulng ASHE Code precedures lauticate a need for mailtlanal gistdellpos to
--- specIfI gg the entstisuJ ASHt Code procedures to control equipment
- - performance,
- - - . . _ _ _ _ . _ calibra tien blocb[_nd a scasuilng precedures to get better reproducibility of ressalts and detectability of througfa-thictness fleus.
I i
25 g 7
i
?
l l .
Minlaum ApML Code requirements de met speclfy the detalls of sacerding requirements that era essential to evalamate fleus. Ibis eleficiency la it.e Code ruten mates it dif ficielt for the IIAC staf f er their ransultants to review, analyse. and assess the UI data to determine the flaw size and .
avalisate the systes safety when the stata are made available to teltC at a later date. IIe psesent data ottelned free UI e ylpeent of uncertain -- - - - and unspecified perinsmance lead to discussions and delays la the review pro-cess resulting in less of lastC staff time and less of plant availability and power gesieratten capacity for the utilities. These situellens definitely , - _ _ _ _ _ . . Delete sieed to be avolded as gf is posslislL lhlk guide l[5lmed'&t &clileving '*' ~~ % g this puupose by issuing secommesulattens that will be supplementary to the eatsting ASME Code UI psecedures. The issue remains whether to wait for encourage legarovement in the development of advanced acDE techalques and continue with ties present AiHE Code procedures resulting la sancartalaties, delays, asd discussions er sof[EnlQil.A present state efTIA art of (enwsstlistLUI. II.e dect-sten appears to be et,vious that we should use conventlanal UI based on engineerimj judgment until seen new techntepaes for flaw detectlen and statuG can be psowed effective in the field. Ihts proposed guide is aimed at pro-
-viding ti.e seteneendattens needed to improve en the A5#f Code UI requirements until psoven advanced seDE tachalques are available.
9 4
k 9 < u g
7.._.. . .
_ ___m_. . -- -m._ -m-- --- . ---,-,ee.- .tes= w .me-- , w - w~ v-- i- -- - ,.e-w= -en w uw = == * . w + - e .- _ - ___..-___m-____._._._
l a . Delete g t Arf *tlejilt 10 AM I) VAluf / IMPACT SI Alf ME st!
Values that will reseilt free this proposed regulatory guldc are auch easter to perceive than the impact, d ich is very difficult to assess leecause the kind of statistical data needed to deterales the real lepect is sleply Delete met avellebte et this ties. One way in which we hope to estimate the lapact -_
ultrascanic testing (Ul) is throuuta ladustry f ee.anack af ter time guide Ines been issued ker coasta ,
W have made aa << tempt, la a qualitative manner, to estimate the value/ ] y lielete tapact of seuulatasy guide positleas, peeltlea by posittoa, as follous: _ ,
System performance che(ks to determine the characteristics of the UI system
- 1. IN5BitttttNI Pf Rf 04eWerf CatfCE5 will lie made shastly before the UI emasinattens. Ibis will pesalt each UI emaalaalloa to be correlated with a particular syntes perfosmance cluk. this Rescading the characteristics of the emaalaatloa system will be practice will help to compare results, matut is; later analysts for deteranclag the locatten, dimenstens, erlente-tien, asul wouwt^t rate of flaws.J5ystess performance cl.ebe to deteemine Delete lhecharacteristicsoftheeslYaserlctentlag(UI)systemwillI.emadeet latee vals close enough that each UI esaminattaa may be terrolated with a .
ll.a examinatloa equipment is assually idle between emaelnattuus. Perfor-parti.cular system ..
performance check.
- _ . . Ibis
. will help
- - _ to
- compara
. - -- res.ults.~j mance cliecks on the examinall64 equipment could be performed slurlaug timese idle these determinatloans will help make it possible to judge whether differences perleds. lhese performance che(ks are snut likely to reduce the sumeer of las et.servations adde at different times are due to changes la lastrument emaalastlesas that a particular UI system could pertens in a year. Ita 484itional charai;teristics or are ese to real changes la the flew stae and i
radiatloa exposure is espected because of this potilloa.
chasecteristics.
It is s ecommended tisat, as a statsum, lastrument checks st. auld be verifled befuse asul af ter eaaatning all the welds that need to be emaalaed la a reactor pressure wessel dueIng one outage.
Perfoemance of these lastrument checks Is likely to add a few thousand dellars in tast equi ut cast and to take I to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> of paastnatloan ting ~ - + - seactor pressure vessel (apy) before asus af ter each Q aalnatlea[By estimating the em4alner's salaryl he be at>out 3SO per hour, these checks st.ould not cost more thaan $100 eacle [
time they are perfeemed. the use of the easelnation esaulpeent is selJun sci.eduled se cIsse that there is emot even a few hours between omaatnationst
- ther=?ere, ti.e idle time on the equipment is snet likely to lacrease, and -'
t
- k. . . _
" 2f
. ~ . . - - . . . . _ _ _ _ . . . .
=pae**' .iww uneemeg g& ea'Be e
e
~ -
> Delete hence the Cost differentla8 et lasurance and elepreciation sa the equipment has not Leen leecluded la the above calculatlees. Bio additional radiation f emposure is espected because of this peeltien. -
t cat 18NA11000 r ' > Delete Auordle.g to this pasilloa system callbratloa should be chected te verify the distance amplitude correction (DAC) curve, as a alaimum, before g Subarticle I-4230, Appendix I,Section XI. A M R&py Code 19;4 edition and af ter euh seactor pressure vessel (arV) emaalaatton (or euh week the I["It Cl* *PPileal to the laspecties of the SpW. roepstred calibration using the basic system is in use, whichever is less) er each time any component (e.g. . calibration block at "the start and flatsk of exh unalnatless, with any change transducer, cat.le, con ====cter, pulser, or receiver) la the examlaation system Ia endelaalloa personnel sad at least every 4 leoisrs si:aring an examisation."
+ -
is cha e d. --
8i*"*** the 1971 rules of Article 4 (I-413). Sectlen V, wt ich are auf erenced 45 to the sammer ISIS Addeada. Subarticle I-42 W. Appencia 1. Section NI. by Sectica XI and now apply to the examinellem of the RFV, require calibratlun ASHL B&FV Code, which applied to Llee la6pection of the SPV. required calibra- (
i agalast the calibration bled only " prior to use of the systca.* It is cust-tion estag tl.e basic callbratloa block each 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. llouever, the present
- t sidered that the present 1977 AM Code rules are aut adespiate to control poten-(1971) sules of Article 4 (1-433).Section V. edilcle are referenced by Sec-l Llal problems la the warlatsoa of instrassent perfosinence characteristics. there-tien kl and now apply to time examination of the SPV. require calibration a en be ore anal af ter ea(In egge[ggggjest is a more agaInst tlse callbration bleCL osely " prior to use of (fle system. It Is ; e approach to lastrassent performance checks. the above position is not seasides ed that ties present (1977) A53E Code reales are not adequate to con- ,
"a IdCitase Oa previously accepted 1974 Code rules on this item but is an incaease trol potential lis ablems la al.e variatloa of instressent performance charac-rules are considered.
teristics. Iherefore, the recommended calibratlea before and after e uh emanination is a moe s reliable approach to lastrument performance checks.
II.a above pasillon is not a ratchet en previously accepted 1975 Code rules ^ ~
e ,
.a.a this itee but is a ratchet if 1977 rules are considered. -
Cosisidering the requirements of Article 4.Section V (8977) the above l leshtten will mean a calibration check eacia week the system is la use or '
t.efore and after a h kPV examination, whichever is less, instead of before each exassinatten. gallbration check agalast the cellbretton block takes IS &c, 30 minutes for manual Ul and automated UI equipment where prowlston ts made to cat tbrate the usesipment withonal having to remove the tressJucers f rom the n otating stasualng esa of the muheelsed scasuier. la some cases, l , ~ Delete i t e ensAmer s have to t>= removed from the scasuting are for calibration of f the UI lasts ament; las these cases, calibration check may take from 30 to ._.
i to aluutes. Ibe added cast of tiee above gy TangedeeslIMcF$5han G terms y
is
'4 #
2e l
l l _ _ _ _ ____ _ . . _ _
g .
e
.e
(..._. ~
of additional t.ime spent. .by the emealm
. . . . - - - - r.J.ihls
. cost le calculated
. . . . - usin0
- - - a th:lete
{50pr,turwageratejandwould.accureachweekeronceforeachEPVexamina-tion, depending en winather er mot the enastnation is completed in less than a week. No additlanal radiation esposure is espected because of this position.
- 3. NEAR-50RfAtf (NAMINAllost AND SunfACE p(50tullott Ibis" positten recommende that an estimation of the capability to effec-tively detect defects at the metal front and back surfaces of the actual cueponent st. auld be made and reported. Ibis will not regulae any adaltional callbastion or examination time I.ut will eleply require an estimate of this ,
tapability t>y the esaminer, which will be reported -
to MAC. Ifhis may take]
. _ ~ . _ . _ ~ . _ _. ,
[4't.ours of ef fort and may cost around $200 for each RPV emassination report sent to HRC. ihis calceslation_le based on assuming $50 per hour wages forJ' N Delete Qieexaminer.fMeadditionalradiationesposureisexpectedbecauseofthis position.
- 4. StAM PNoillE Ihla position recommends that the beam profile (for each search unit used) slould t>e deterutned if any significant flaws are detected during item kPV camminatloes.
Assuming that no more Linas three search asalts are llkely to les used during an kPV eaaminellen, this step is likely to require no more than 2 -
Imurs of enantuations -
time.[Iherefore, this 12am praille determination -. DeIett
. ~ , . ~ ~
shoulf cost ~no more than $.100 fo.r e_ac..h .R.P.V. emani.n.at.l.o.se
. . ..b.as.ed.,on.. a (50 gr (t.ourwage.eate.
I He additional radiation espesure 16 expected because of this 3.asit ion.
- 5. SCANetlNG WitD-MtlAt INltRfACE
'e %
1his position rec.ammesuis that the beam angles used to scan welds should l
l be leased on weld /seereat metal laterf ace geeometry azul at least one of these l
angles should las such Llaat the been is almost perpendicular (115 degrees f .
' 29 I
t ':
=
a w
B A
1 s to the peependiceslar) to the weld /paraat metal laterf ace, uG .11 can be demonstrated that large (Code-isnacceptable) planar flaws isnf amely erlanted can be detected by the UI t whnique. _
~~
- 9.10.11 On the basis of informellen available, it appears Lliat it is difficult
- ete to detect large planar flaws (e.g., service-laduced fatigue e stress corrostoa cracks) osiented at right angles to the surface, uslag the Ah Code UI procedure. Huwever, the option is being provided to 8*=aastrate that such '
flaws can be located by conventlenal methods er by uslag new advances in UI t.*(1.niques. la ti.ese rases, the techalapse will be acceptable as a .
(W Wd-
/ . among others, sincuM M welammetric emanination method. Other:4tse, the use of high-latensity radt- .
egraphy er tandras pra,be UI j h h d %jh]@]Iniyi ,
C ~ ~ " ~
the above type of fleef*la the most significant -mosMllflML te
~ ' ~ ~ last time detect. Because of this, the present recumeendatlases are being asde des'ptlE their potential lepect en cost and radiatten espesure.
ihe lx,tesitial lepact may be es follows:
- a. tatra tekC staff time may be needed to evaluate the afaectiveness of UI tecluilquenf$ a generic basta[e detect perpendice:lar planar flaws. ,
Af ter tett.s'ilques are recognized to acceeplish the above, IIAC staf f time tiaat is beisag spent currently on evaluating problems on a plant-by plant basis is expected to be reduced coasta.arably.
- b. Beactor dowe ime may lacrease, dependlag on the examinatlee time differentials between the conventional and r ned techalques. this may,_.s leewever, be offset by a reductlen la the doin f $ded currently to evaluate CNe'It4IIe (liat sometimes require furtiner i Currcally needed for 8,RC esperts to evaluate data inat sometimes seguires furtiner datal,yleRCemphEsenac
'I0
~'
clarifications and seemaninations. clarification ashi reenaminatlast
'* Probability of Detecting Planar Defects la lleavy Wall Welds by Ultrasealc lecivilgues Accurding to falsting Codes," Dr. Ing. llasta-Jurgen lleyer, quellty Deputeent of M. A.N. , flured.org, S 8500 sternberg !!S.
laterim Line lectunical leoas te te Cratking,gart en SWR fee beater leuafG-6'll2, July 1977, p. 3. and Central Red Drive Return Analysts of the Ultrasonic Esamtmations of PVSC Weld Specimens 155, 202, and 201," R. A. Buchenan, Pressure Vessel basearch Committee (PWRC) geport, August l$16.
N O"Samusasy of the Detection and Evaluellom of Ultrasonic Indications - Eibala ItatcI Unit I ke ctor Pressure vessel," January 1972 Georgia Power Company.
8 '
30 g
7.
S e
- c. A.kattlenal cost might be facierred la changes needed te edal trans =
docers or data gatherlag capability to. estating automated equipment er to eatemate current seseman emanimettens. Autenettaa of cierrent manual tech-elapses la litely to reduce ra11atten empesure ta persammel.
- 6. SllissG AIA RfC0eolHG OF leelCATIOel5 e.1 Ir m ling ladicatlans g3,gege Ihts pesillen recommeads the recording of travelleg ladicatleas. If '
EfW welds do not have any indicatleas in the welds wisose travel indicatlan en it.e scseen is larger thu the ladicatten en the screen from the callbra- (5 inch hole for 412 inch seeld Lbickness, 3f8 laub holc for an 8 luch tima heles h h h o t jg= q,glg (lg(( h ig,_jjg= 3,.g ' jar M {lticknessy tl.ls reusemesuiction will not result la eay more recording ef Indicattens. thickness).
It tlie kPV welds helag examined have several Indicattens witl travel la emcess el the callbratten bSie diameter, the emaalmetton and recordlag time ,
Ib8 will i+e lucreased ler avestigatloa of these flaws, depending en tha number 3
of these ludicattens. Slag inclustens la welds are generally long cylla
- drical defects asas de set have much depth unless they are associated with st.rtnkage er service-laduced tracts. lhese slag tactustens are not empacted to leas sa== ti.e aandser of ladicottons that will be recorded. Increase la anaalmetten Llane will depend on the mamaber, site, and complamity of geometry .
of thsough-thicksness ladications. ,
ler RPW girth or mesale welds winere emaninattaa is performed by auto-mated eq.sipeemt asuf data are recorded en tape, this posillon will mesa no leicsease lasmaalaatloatimeerradiattenespesure[butlaterpretattom, analysts, and reportlag time for Eliese depth ladications will lacrease, the entra burdesa la terms of dallar cost will depend en the number, site, and complealty of flaws, and there is ao rational basis or data available __
at this tia.e to estlaate the Increase in est of emastaattaa.
Sur krV welds, mostly natale welds, wt.ere emaatmetlea la performed manually esmi Jate are c.at recorded on tape, this position will meam entra examinatlea time and lacreased radiattaa emposure to the emaatners.
Increase la deltar cost arJ radiatlea exposure will depend agala sa the r
31 t 7
l 3.
a 1 e I
l l
e u-r, size, ased complealty of ladications, and thera is as basis er data available to estlante this increase.
6.2 leontravell g laelicatleas II.ls peeltlem mise receameemds the recordlag of sheatravellDgl IDdicati above20%DAClevel[thatpersistforedlstanceofmorethanIlackplus the beam spread. According to in-5320. Radlagsaphic Actoptesace Stanlards, Sectlen lit. Divisten 8. A58qE S&PW Code, ISPI editlen, flaws larger than a
3/4 ef'all. inch for weld thicknesses above 2-1/4 inclies are met acceptable.
Because of this reylrement, it is enpacted that me flaws larger than 3/4
' ([M isAla la length are present la the RPV welds, anal if ladiratleas are detected that suggest flaws larger than 3/4 h lach, there is a strong
. possibility that these may be service-indisced flaws. Service-induced flaws are rase in kru welds, and it is Lleasefore not espected that additlanal f amiltatlosis would have to be recorded because of thls positlea. liowever, if sinl. Indicattens (over I lach) are detected, exaelnatten Else for auto-mated retarding and emaninallen ties plus radiatten enposure for manusal lii examinattuns will be increased. There is ne rational basis or data avellable to estimate the impact of this part (6.2) of this regulatory positlea.
F. 21PoetIIlmi of Itt5 tit 15 lhls positten receamends that the areas regnetred to be examined by the A5Ht Code that have eiet been ef fectlvely emaalaed and an estimate of 2sser band la slalog time flaws stieutd be brouglit to the attentlea of Lt.e '
' aey le64C wless the results are reported. Ihis after ska about i hours in repert writing El.a. jf E 3iH E M Ifer thTs effe'rt is estlaaI R Q ^
0 baEed on a $50 per lemur wage eate. [ '
Delete t
ITt LM_t MLAllM It should be noted that recommendellens el this guide are met intended to apply to passervice emaninatten tests alrea% completed. ifowever, the tt Y 52
___ . .~
g ,
-.__-____ ___-- a - w - -e - w + . _ - - -
2 a
e e
licensees may a.easider repeatlag their preservice emaalaatisa testa er uslag the twoommendatleas et this gulde any Line at their optima to aveld possible flaw laterpretattee problems at a later date, f law laterpretatten problems may occur if travellag ladicattens identified as significant accordlag to the recommendattens of this guide de met correlate ulth preservice valuestric sept e esults and hence would be assumed to have basa sarwice laduced. It would les difficult to show that these ladications erlse from fabricatloa flaws.
Iherefere.( iconsees would be well advised to consider the above possibilities. -
Delete I-
'I G r 33 g
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ . _ _ . _ _ _ _ _ . - . . , . _ . . _ _ . _ _