ML19221A862
| ML19221A862 | |
| Person / Time | |
|---|---|
| Issue date: | 12/28/1972 |
| From: | NRC OFFICE OF STANDARDS DEVELOPMENT |
| To: | |
| References | |
| REGGD-01.134, REGGD-1.134, NUDOCS 7907100147 | |
| Download: ML19221A862 (3) | |
Text
w a
/
12/28'72
~
u' U.S. ATOMIC ENEFIGY COMMISSION
.r M.S.P REGUi_A rO RY G L 8 D E 4,
/
DIRECTORATE OF REGULATORY STANDARDS
%s c? '
REGULATORY GUIDE 1.34 CONTROL OF ELECTSUSLAG WELD PROPERTIES A. !NTHODUCTION Quahtications."3 which mcludes the requuements for General Design Critenan 1, "Quahty Standards and the pnvedure quahfication f or welds. Reuew of the Records." of Appendix A to 10 CFR Part 50," General requirements of the procedure quahfication stated in Design Cnteria for Nuclear Power Plants." requires that Section IX indicates that supplementary requuements structures, systems, and components important to safety are desuable to proude assurance of adequate weld be designed, fabricated, erected, and tested to quahty metal properties when the electreslag weldmg process is standa rds commensurate with the importance of the used. De assurance of satisfactory electroslag welds for safety function to be performed. Appendix B to 10 CFR low. alloy steel and stainless steel can be increased by Part 50, "Quahty Assurance Criteria for Nuclear Power maintainmg a weld metal sohdification blendntic)
Plants and Fuel Reprocessing Plants," reqmres that pattern with a strong mtergranular bond m the center of measures be estabbshed to assure matenals control and the weld. A number of electroslag weldmg process control of special processes such as welding, and that variables, such as slag pool depth, electrode feed rate and proper testmg be performed. This guide desenbes an osediation, current, voltage, and slag cotiductivity, have acceptable method of implementing these requirements been shown to in0uence the weld metal solidification wuh regard to the control of weld properties when pattern. If the combmation of pm
. oiables tesults m fabricat;ng electroslag w elds f or nuclear components a deep pool of molten weld metal, the crystalhne austenitie materials. This guide (dendutic) growth duection from the pool sides wd'jom made of ferntic or apphes to light water ieactors. The Advisory Cummittee at an obtuse angle in the center of the weld and cracks on Reactor Safeguards has been consulted conceming may deselop because of the weaker centerhne bond this guide and has concurred in the regulatory position.
between dendrites. Section I-1 in Egure A of tha guide illustrates the dendritte growth pattern. A combmation B. DISCUSSION of process variables resultmg in a sh:.ow pool of molten The Amencan Society of Mechanical Engmeers weld metal will promote a dendntic growth pattern with n acute joinmg angle and will result in a strong (ASME) Boiler and Pressure Vessei Code, Section Ill, centerline bond. Acceptable w elds sbuuld show a
" Nuclear Power Plant Components,"' specifies certain requuements associated wHn manufactunng Class I and dendntic freezing pattern with a joining angle of len 2 components. Although not presently withm the scope than 90 degrees in the w eld center.
of Section 111, welds for core support structures should, as a mirumum, meet the requirements specified for Class Tests should be made to assure that the acceptable weid metal sohdification pattern specified above is I components.
obtained and that unacceptable patterns will not result.
Procedure Qualifications The use of a macro-etch exammation is a satisfactory technique to determme the weld sohdification pattern.
2 Section lil requires adherence to ASME Boder and Pr essure Vessel Code Section IX,
" Welding and it should be included in the procedure quahtication.
Section 111, as modilled by the Summer 1972
' Copies may be obt amed from American Society of Addenda, requires as part of the procedure quahtication Mec hamcal Engneers, l'nited Lnpneenng Center,345 East 47th for low-alloy steel welds that dropweight tests be made Street, New York, New York 10017 2ASME H&PVC, Section ill and Summer 1972 Addenda to Sestion Ill.
' ASMI B&PVC Section IX and Code Case 13554.
USAEC REGULATORY CtHOG C Op. e Of pubi.shed gmdes mov he Obte ned Dy request uid Cat q the d.v.s Ons des red ta ihe U S. A tom.C E regy COmmiss On. vWeshingtOn DL 70545.
R egwe t or, Gu. des ce used
.o dem.te and mem e evedente 10 t he pubhc Attent On Derector of Reguistory Stenderds Comnwnts and suwest One 'Or artproverrents en these guides o'e enCou aged end should te sent 90 the SPr est ery met hods eCCOOtah6e tu the AE C ReguietOry staf f of empementmg specif'C padl Of r
t he C OmmM *0n 's r egu lat ions. to je eneete vethnsques used by the steH en Of the Commimon. U S Atom'c E nergy COmmess-notOn i 21 es evetuateng 3DeUht D'Ohtems or post ulated a(Codertts C' 10 provide gu=dence 'O Attent On Chief. Publ c ProceeG ngs statt
{
aggW.A n ts Regulator y Gu. des are aOc subst'twies 'Or r*gules >Oas sad (Ornonance sw.t h t he'11 es MOf requaed Methods and solut+One d f o tent If 0m thOee set Out in IM gu'fsPs are Maued en tPe IOllowwe'ig ten beOed &Wes+0ns r
u tte gu Cles edt be acceptabag of they prOvede e tes's f or the find'ags requ.s.te 10 1 Powne' Reactors 6 Products the reswance Or 3 nt anuancf of a Deren't or intense by the CornmisseOn Roseerc s and Tesi Rest fors 7 T r easoor t er.on 2
e 3 F ue's erid uater ees F ec.i.t es 8 Occuort Ona' Heat,.
gu des Wdl be rev4ed period %eHV es eDOr 0pr s'e 'O ef tommodore 4 E nwarOnmentef and S+ ng 9 Ant trust Rev.ew P ub bshed e
Comr'1 Pats #^d to rehott FMPW i 'f0' met'On Or e s per ' ente 6 Meter iens emi P'ent P s tec t.on 10 Gener er t
1907100/4 7
14% d C I C f ilill1C I!!J I C t iv ells C l e a lipC l a i li t C (Nl ggg ) {ti[
liiillIs t ls e s pel lClis t M lill e ls i l l i 'sl o f w cl6'vil base mela!. the heat Jllested /onc (ll \\/). and the u cld snindcw sicci g ompoucm, h n show n ih n, inLne in melal f oi Claw I seweh. I oi Clau ' s emch. Sct i nin ill t he u c!J ohal u a n..n o cn n n o.o i po 1 Ic m u In o i h, p iq$cils s p ulilical.ill.1 t e ui li ikd Ili 6.hlli o in l
slJIn ll1al tlle Inced l6it unp.h t IJsltlle dnsuld be pi n occw is Jeteunmed bs the ownei and nhiaJeJ m the dcun ths w cht H u :. I siiin im e.mJ ina h n u il pow i e oc s pu itica t ion s. I spenense he show n ilut :he icteieme cenculk au c pl a ble. Io wne ilui ihe pmuiw uoM t e m;ri at u re for the quenshed anJ tempeied LOA l) welds
.n c u nsl.h ion. ihe wchlme pos ss low aHo, steel elestroslag weld metal a generalh ingher sinihed m the po s edme 41.athanon shoalJ Fe than f or the adptent base metal. and the welJ metal momtored dunng the w eldme pnsess.
estabhshes the nummum pressuuntion t e m pe r a t u re C. REGULATORY POSITION mstead of the base metal. Io prmide a measure of auurante that the weld metal has respondeJ adequate,
M m
mndWd to the Q&T heat treatment and to obiam a referense e & MruNn requuemenn sp:afted toi temperature. the prosedure quahtication shou!J speuty g,
i;;: n 1 m
,ne m hkmo% wdd requ: red by Section 111 he that unpact-testing h
t we W CW l M 2
.n insluded for (lass 2 sessek. All results of the abme tests M aM enn &dd sm@ we um Hi and eummations should be includeJ m a certihed and Sesti-n IV supplemented by ti e hh n e quahlication test report.
1.
1 he pavedure quatili ati,lo' f or low -alby ' acel arW Production helds stamlew steel w eldme should requne tlut a.
Process s ar uhles su.h
.n Jag p' d depth.
The procedure quahfication by itsell does not assure electroJe teed i :te anJ osallation t ur:en t. Utv. and that low-alloy eeel production welds w dl meet the weld slag conJuctnity be selectcJ to proJuce a sohditisatun soh di fic a t ion pa t te m and mechanhal p m pertF pattern (denJntic gum pattem) wah a tommg angle of requuements specified in the procedure quahtication. To less than un degrees m the welJ tenter.
nere that welJs do comph, it n necessary that the m the A
O W be pe i t or mt J produ tion welds themsehes be exammed.
longitudmal w elJ ducctmn of the centei plane a. loss the s
weld Irom base metal to bne metal as siewn m I igme A Where the electroslag welJmg process is used for of tlas gmde. The test should senty that the desned fongituJ:ral welds m low-alloy steel sesseh. it is sohdification pattem resultmg tiom reenlatory positio:
t ost om ar y to contmue the w eldmg pr oc ew into l.a. ahme has been obtamtJ and that the " eld n Iree of pmlon ganons to the base meial. These prolonganons unacceptaHe fissures er crads: and oniam both base metal and w eld mt al anJ proude s
Impact testmg be specihed for (, lass, low-alloy c.
,t e mechamcal representaine sa mples for testmg pr opei n es of. the base metal and the we. ] metal..The steel sessels, m accordanse with paragraph N(.,310 of Sectmn Illc weld suhdoicatmo pattem man be datermmol fror.: weld samples taxen f rom these prolongations. A aacro-etch tes! on a weld center sample taken across the w Id from
. Le rnults of the tesn requaed by regulatory poutmn 1. abuse should be meluded m the cerotied bee metal to bee metal m the duection of ths w eld quahfkation test report.
pmgresuun. as shown in Figure A of this guide w ould be an aucptable method of sentymg that the specilled sohdification pattern has been obtamed aaJ this test 3.
F or longitudmal production welds of low-alloy steel should be made. An acceptaHe alternatne to the seweh. matenal contaming base metal and weld metal macro-etsh test for assunng the soundness of the center t ak en from weld prolongations should be tested as weld metal would be to perform an unpact test with the f ollow s:
a.
Tenue and npact t esi s snmhr to those specimen north located at the w eld cer.ter as shown m Figure A of this guide.
requued for the bee metal by paragraph Nib 3211(d) of Section 111 should be made to de:ntmne the mechamcal Section 111. as modified by the Summer 1972 propetties of the quenched and tempered wehl metal:
AJdenda. spe cifies requnement> tur low -alloy weld b.
To senty that the specified w eld solidificanon met ah but it does not specificalh cmcr
- he situanon pattern has been obtamed and that the weld center a where the v eld is OAT heat treated. Seenon 111 does wund, one of the follow mg methods should he used requae that nutenal haine its mechanu! propernes (Il A macro-etsh test smular to requuement of enhansed by a heat t r eat men t must subsequently be regulatory position 1.b abose. or tested to esure the elfestneness of the heat treatment.
(h Impact testmg with the speumen not<h To proude this assuranse for lowelloy steel eleitms!ag located at the weld center as shown in Figure A of this produenon welds, the methamcal propert es of the weld guide.
The tests spe;ified m regulatory posinons 3.a.
metal should be determmed imm the weld prolong.ncn c.
by tesa simdar to those requued for the QF1 ba se and 3.b. abme should be apphed to metal. Ior Class 2 sessels it v ould not be necessary to (1) Each of the welds for Class I sessels.
test all electroslag w eld seams. but at least one welJ (2) One welJ per shell course f or Class 2 1 2 b
<\\ M should be tested f or each shell tourse.
s essch.
m2
_4 Foi producinm welds for austenitic stamlew stcei 5.
In ihe esent that properties obtamed liinn tests coie support structures and fluid system components, identified m regulator y poutions 3. and 4. abuse.ve out lhe production welding should be mtinitored to serity acceptable addition.il proseJure quahfications shotile be complia. ice with the knuts for the process sanables perf ormed in accordance with regulatory position 1.
spetilled in the procedure quahfication.
ab m e.
Charpy speimen, Section 111 locat'on and orientation Charpy soecimen, center Weld centerlines location and nrientat;or Base metal ill
/0 %T (Til I
I I
I I
I f
O 2
{
T - section thickness 1-n
%T
%T vi t s sitt' l
l WELD CROSS-SECTION O
k j
(I 4'/Ag$
3
' / /j#O We!d prolongtion
,/
O*
or test section
'O p//AsN
=
f
(//f R' 64Ns e
A Acuta joining angle of dendrites LONGITUDINAL SECTION i - l 125 165 WELD CROSS-SECTION SHOWING SOLIDIFICATION PATTERN AND CHARPY TEST SPECIMENS FIGURE A 1.34-3