ML20039F096
| ML20039F096 | |
| Person / Time | |
|---|---|
| Site: | 05000561 |
| Issue date: | 06/04/1977 |
| From: | Taylor J BABCOCK & WILCOX CO. |
| To: | Boyd R Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML111090060 | List:
|
| References | |
| FOIA-80-515, FOIA-80-555 NUDOCS 8201110850 | |
| Download: ML20039F096 (9) | |
Text
NRC e unu in U.O. NUCLE An nr t,UL ATpy touMi::ssoN ooc KLT NUMotr.
50-561 naaf
""I" NRC DISTRIBUTION eor PART 50 DOCKET MATERI AL T'a.
FROM:
CATc os ooCUMENT Babcock & Wilcox 6/4/77 Lynchburg, Va.
- r. Roger S. Boyd u
,,,,,,g g,,,k7 7 James H. Taylor 6/ i OL.
sR ONOTORi2ED PROP INPUT FORM Nt/MBEn Or COPIES RECElVCD C on sciN AL OUNC LAssiriE D i
OCoPv DESCniPTION E NCLOSU RE l
l Consists of revised B-SAR-205 material -
l modifying their earlier response to 122.9
'i and related B-SAR 205 test material to compIly-with the Staf f position concerning methods for determination of de'lta ferrite levels in austenitic stainless
- steel welds.....
l 1
' PLANT NAME:
I
'SAR S
JL 6/13/77
( 2-P )
'(6-P)
SAFETY FO8 ACT!ONilNFOHf.iATION ENVTRO
/I ASSIGNED AD:
i ~ F V8 P O BRA _N.CH CHIW *
/d u e//6 A S SI C'."T O A O:
b ~
- NC11 C11IEF:
[/
IECT MANAGER:
c o.t PROJECT !TIAGER?
(2 w. ASST.:
f ud hwu E LIC. ASST.!
~s.
INTERNAL DISTPIBUTION
(/
REQ [JLE I
SYSTEMS SAFETY
} pi g g s-rug SIT 3.SAy gg &
J[RC PDn llEISEM.\\N A,.gggs.SCO ENV G9 E 61137S 7 Iac$
SciiR0eDr.R pe_ BENZ,R0yA DENT 03 & uuttra
[/t.
_L9:ll.D_
._.1Al?iAS cCSSICK & STAFF ENGINEERING IPPOL_ITO ENy_IP,0_ TEC11 _
MLtc JACCAnnY
~/I KI1M'LOQ_
ERNSJ CASE 7
KNIC,11T
!!ANAUER
/
- SilNEl' I
nALLago Jt4];LEqs
/
OPERAllEQ_REACTOP.S STAnCIER PAULI,CKI SIg]1Q,,
SITE __TIcu -
f.ROJECT ". mig.Cl!EET RI: ACTOR SAFETY 0 'ERATJ?iG dCII.
/ Cle!I LI.
T1 /
11011)
IROSS
_E,ISigqt_tTr STEPI' J'....C OI.L I N S JOVAK S!!AO 11 ult!Att liOllSTON ROSZTOCZY BAEli PETERSON 7 CIII:CK ME1.TZ
,BLrLER_
SITE._AEiLY3IS CttJf ti'.S
/ VOLL!:EIL M__11UNCit lit:1.TrnES AT & I SKOVIIOLT SALTZMAN
,/,__J..COLI. INS nu rncac e varm n L X ll.itu AL OtulilllillIION
~
CON illOL NUMilr H it :
NAT IAn:
.T C:
lu:G. VTE
,,En001:11AyEN. NAT,IldL_
t
[
I til.!tinSON(onn Q
.[ N$JC: _.
.I A l'Dl!..
771650017 ASI.n ;
CON:;t!!.TANTS
./AcitSMYS C/: CNT )4-7 ~
C. 4_[ ]
l 8201110850 810403 PDR FOIA MADDEN 80-515 PDR
Babcock &Wilcox
% ercener.tioncrop P.O. Box 1260 Lynenburg, Va. 24505 Telephone: (804) 384 5111
' 3-June 4, 1977
~
DOCKET STN 50-561 Office of Nuclear Reactor Regulation
$0N1 W 7 d ATTN:
Mr. Roger S. Boyd, Director
,,e N,r. g #
3)
Division of Project Management
'S U. S. Nuclear Regulatory Commission r
Washington, D.C.
20555 y
Subject:
B-SAR-205 - Revised B6W Position
Dear Mr. Boyd:
B6W has established a revised position with regard to NRC request 122.9 and hereby submits the attached draft copies of revised B-SAR material to expedite review and acceptance by the Staff.
In summary, the attached material modifies our earlier response to 122.9 and related B-SAR-205 test material to comply with the Staff position concerning methods for deter-mination of delta ferrite levels in austenitic stainless steel welds.
This letter is a commitment that the Babcock 6 Wilcox Ccmpany will formally include the attached modified material into the B-SAR-205 in Amendment 16, scheduled for submittal to NRC on or about June 28, 1977.
Very truly yours,
? d.
/
/
James H. Tay1'or Manager, Licensing JHT:dsf Enclosures 771650017 The Babcock & Wilcox Cornpany / Estact'shed 1867
4 4
' Rahrnck&WNCOX i
Mr. Roger S. Boyd Page 2 June 4, 1977 i
cc:
R. B. Borsum (B6W)(2)
J U. S. Nuclear Regulatory Commission (1) l Office of Inspection and Enforcement - Region IV 611 Ryan Plaza Drive - Suite 1000 Arlington, Texas 76012 i
Mr. Neil Thomasson (3)
Attn:
Loretta Long Office of Radiation Programs Environmental Protection Agency Room 647A East Tower Waterside Mall 401 M Street, S.W.
Washington, D.C.
20460 P
Mr. A. J. Oswald (1)
EG6G Idaho, Inc.
P. O. Box 1625 Idaho Falls, Idaho 83401 l
B 1
1 k
B-SAR-205 Am:nd. 16 3.12.31.
Regulatory Guide 1.31 -- Control of Stainless Steel Welding (Rev 1, June 1973)
B-SAR=205 addresses the modifications to this guide contained in NRC Branch Technical Position MTEB 5-1 (refer to NRC Standard Review Plan, Section 5.2.3) in sections 4.2.2, 4.2.3, 5.2.3.4, 5.4.1.4, and 6.1.1.
The provisions dis-cussed in these sections address alternatives to parts 3 and 4 of this posi-tion. The B&W provisions are su=marized as follows: The chemistry of austen-itic stainless steel is controlled so that the predicted microstructure of the weld deposit minimizes the probability of microfissures. Except for weld me-tais that have demonstrated resistance to microfissuring (e.g., AWS E16-8-2 and similar composition wire), all austenitic stainless steel weld metals will have a minimum of 5% delta ferrite content as required by the ASME Code, Sec-tion III. In addition, B&W specifies that austenitic stainless steel weld ma-terials for Class 1, 2, and CS (core support) components fall in the range of 5-20% delta ferrite when r:easured, as required by the ASME Code,Section III, Winter 1976 Addenda, using magnetic permeability techniques.
l16 3.12.32.
Regulatory Guide 1.32 - Use of IEEE Standard 308-1971,
" Criteria for Class 1E Electrical Systems for Nuclear Power Generating Stations" (August 1972)
This guide is addressed in the applicant's SAR.
3.12.33.
Regulatory Guide 1.33 -- Quality Assurance Program Requirements -- Operations (November 1972)
This guide is addressed in the applicant's SAR.
3.12.34.
Regulatory Guide 1.34 - Control of Electroslag Weld Properties (December 1972)
The Babcock-205 complies with this guide as discussed in section 5.2.3.3 and 5.4.1.4 for low-alloy steel materials and in section 5.2.3.4 for austenitic materials. B&W's compliance is as follows: Electroslag welding on Class 1, 2, and CS components vthin the B&W scope of supply is limited to the RC pump cas-1 ing.
The controls imposed on this welding process and weld qualifications meet the provisions of parts c.1, c.2, and c.4 of this Regulatory Guide. Part c.3 is not applicable since RC pump casing welds are of austenitic stainless steel.
If electroslag welding is utilized on other class 1, 2, and CS compo-nents within the B&W scope of supply, cuitable controls will be imposed.
3.12.35.
icgulatory Guide 1.35 -- Inservice Surveillance of Ungranted Tendons in Prestressed Concrete Containment Structures (Rev 2, January 1976)
This guide is addressed in the applicant's SAR.
3.12.36.
Regulatory Guide 1.36 - Nonmetallic Thermal Insulation for Austenitic Stainless Steel (February 1973)
Compliance with this guide is addressed in the applicant's SAR.
3.12-5 Babcock & )Milcox 6
B-SAR-205 Amend. 16
. Weld practices are controlled to avoid excessive sensitization of the base me-lal heat-af fected zone (HAZ) of the austenitic stainless steel weldments. Weld-ing procedures are controlled to meet the following guidelines:
1.
Limit the amount of heat input. during fabrication based on shop practices of specifying amperage, voltcge, and maximum bead widths.
2.
Limit interpass temperature (nominally 350F maximum).
3.
Avoid excessive weaving.
Quality control personnel will conduct periodic checks to ensure that these procedures are actually followed. An intergranular corrosion test per ASTM A-393 or A-262 or their equivalent will be performed for each welding process to be used to weld material having a specified maximum carbon content greater than 0.03%.
These tests will confirm that the weld processes used will not produce severe sensitization in the weld HAZs.
The chemistry of austenitic stainless steel weld metal is controlled so that the predicted microstructure of the veld deposit eliminates the probability of microfissures. Except for weld metals that have demonstrated resistance to microfissures without ferrite requirements (e.g., AWS E16-8-2 and similar com-position wire), all austenitic stainless steel weld metals will have a minimum of 5% delta ferrite content as required by the ASME Code,Section III.
In addition to the Code requirements, B&W specifies that austenitic stainless steel veld materials for reactor CSA components fall into the range of 5-20%
ielta ferrite when measured as required by the ASME Code,Section III, using 16 magnetic permeability test methods. Materials qualified as described above are acceptable as indicated by the revised NRC position on Regulatory Guide 1.31,
" Control of Stainless Steel Welding," dated 4/11/74.
All production welding is monitored to ensure compliance with the variables used for veld procedure qualification. Production weld testing for delta fer-rite measurement, as indicated by provisions 3 and 4 of the NRC position dated 4/11/74, is not considered necessary to obtain satisf actory welds when weld me-16 tals are qualified using magnetic measuring devices. B&W test data from pro-duction velds justify this position.
All welding is performed in compliance with the applicable ASME Code edition and addenda to Sections III and IX.
The modifications to these documents in Regulatory Guide 1.71, " Welder Qualification for Areas of Limited Accessibili-ties," are not applicable to reactor internals components manufactured by B&W since design and shop manufacturing procedures do not require manual welding under severely limited access or visibility conditions. B&W procedures require monitoring of manual weld processes for compliance with qualification require-i ments, and such monitoring is included in B&W Quality Control.
1 4.2.2.2.
Description and Drawings l
Reactor CSA components include the plenum and core support cylinder assemblies.
The core support cylinder assembly comprises the core support cylinder, reactor internals vent assemblies, core basket assembly, lower grid assembly, flow dis-tributor, incore instrument guide tubes, and surveillance holder tubes.
l 1
i 4.2-18 Babcock & VVilcox
B-SAR-205 Amend. 16 a.
Limitation of the amount of heat input during fabrication based on practices of specifying amperage, voltage, and maximum bead width.
b.
Limitation of interpass temperature.
c.
Avoidance of excessive weaving.
An intergranular corrosion test per ASIM A-393, -262, or the equivalent will be performed for each welding process to be used on the RCPB weld material having a specified maximum carbon content greater than 0.03%.
The chemistry of austenitic stainless steel is controlled on RCPB components so that the predicted microstructure of the veld deposit eliminates the prob-ability of microfissuring. All austenitic stainless steel weld matals will have specified delta ferrice content in the range of 5-20%.
Production veld-ing is monitored to ensure compliance with the variables used in the weld pro-cedure qualification. Production veld testing for delta ferrite measurement as indicated by provisions 3 and 4 of the NRC position dated 4/11/74 on Reg-ulatory Guide 1.31 is not considered necessary to obtain satisfactory welds when weld metals are qualified using magnetic permeability test methods.
l16 B&W test data from production welds justify this position.
The materials used for the CRDM were selected to provide assurance that no significant chemical or stress corrosion will occur during service life.
The corrosion resistance of both the SA-453, Grade 660 (an austenitic pre-cipitation hardening alloy) and the type 403 martensitic stainless steel is excellent under the expected RC water chemistry conditions described in Ta-ble 5.2-4.
The excellent operating experience aith these alloys in simi-larly controlled PWR environments further demonstrates their suitability for use in this application. The minimum specified tempering temperature for the type 403 martensitic stainless steel center section of the CRDM pressure boundary is ll25F in accordance with ASME Code Case 1337. Tempering this material at ll25F or above will ensure that the material retains good corro-sion resistance and fracture toughness.
All parts of the CRDMs that are in contact aith the reactor coolant or are part of the RCPB meet the requirements of B&W cleanness specifications.
These specifications limit the level of contamination present on the surfaces that will contact reactor coolant. Methods and materials used in cleaning and fabricating meterials are restricted by the specifications and are used only in accordance with written procedures. All cleaning is performed in an environment suitable for these operations. Af ter the final c1 caning, clean-liness is maintained by scaling or wrapping in selected material, such as polyethylene.
Specifications for cleanliness and contaminant control of the CRDM are equivalent to the requirements discussed in section 5.2.3.4.1.2.
- 4. Radiation Damage - The ef f ect of irradiation on cladding materials, neutron absorber material, and poison materials is considered in the analysis of the reactivity control components.
Irradiation exposure decreases the ductility and increases the yield strength of the component cladding materials.
The cladding material effects are based on the ASME Code,Section IV, for 304 stainless steel materials and on the information presented in 4.2.1.3 for Zircaloy materials.
Radiation ef fects are also a consideration in the ma-terial selection, design, and f abrication of the CRDM, especially for parts exposed to the reactor coolant.
Babcock & \\Vilcox 4.2-27
B-SAR-205 Amend, 16 3
o.
.+
i
-as an adequate basis for compliance with Appendix B to 10 CFR 50 for on-site leaning. This function is normally the responsibility of the plant owner, and this standard is reflected in the owner's procedures applicable to this.
work. B&W provides appropriate instructions and consultation to aid in com-pliance with this guide as described in sections 2.2.2 and 14 of B&W Topical Report BAW-10096A.4 i
As described above, B&W specifies cleanliness requirements during the fabrica-tion and shipment of safety-related components to ensure that these components arrive at the site in satisfactory condition. These cleanliness requirements include consideration of chemical compounds that are known to contribute to i
intergranular cracking or stress corrosion cracking of stainless steel or l
nickel alloys. Water che W try is controlled during initial fill, testing, I
l and operation to prevent aa environment that may be conducive to material fail-i ure.
I I
5.2.3.4.1.3.
Characteristics and Mechanical Properties
+
of Cold-Worked Austenitic Stainless Steels 4
Specification of cold worked austenitic stainless steels is not anticipated for components of the RCPB.
If such materials are specified at yield strength levels greater than 90,000 psi, assurance of their compatibility with the re-i I
l actor coolant will be provided.
5.2.3.4.2.
Control of Welding 1
____5.2.3.4.2.1.
Avoidance of Hot Cracking., _.
The chemistry of austenitic stainless steal is controlled so that the predicted microst;ucture of the weld deposit minimizes the probability of microfissures.
I Except for those veld metals that have demonstrated resistance to microfissures (e.g., AWS E16-8-2 and similar composition wire), all austenitic stainless steel weld metals will have a minimum of 5% delta ferrite content as required by the ASME Code,Section III, edition and addenda listed in Table 5.2-1.
In i
addition to the code requirements, B&W specifies that the delta ferrite con-l tent of austenitic stainless steel veld materials for RCPB components f all in j
'the range of 5-20%, inclusive The delta ferrite levcis are measured as re-quired by the ASME Code,Section III, using magnetic permeability test tech-16 i
niques. Riterials qualified as described above are acceptable as indicated by the revised NRC position on Regulatory Guide 1.31 " Control of Stainless Steel Welding" dated April 11, 1974 (MTEB 5-1).
l I
All ptoduction welding is monitored to assure compliance with the heat input and other variables used for weld procedure qualification.
Production veld.csting for delta ferrite measurement as indicated by provi-sions 3 and 4 of NRC position KTEB 5-1 is not considered necessary to obtain satisfactory welds when weld metals are qualified using magnetic measuring 16 devices. B&W test data from production welds justities this position.
The primary method of controlling microfissuring or hot cracking in austenitic _.__ _ _
stainless steel weldments advanced in Regulatory Guide 1.31 is control of delta j
ferrite, both in veld metal qualification tests and in production'velding. In response to Regulatory Guide 1.31. B&W has instituted control of delta ferrite.
_.- 5. 2-13 Babcock s.Wilcox l
i i
g
1 s
B-SAR-305 Amend. 16
..Use of cold worked austenitic stainless steels is not anticipated for pressure Noundary components of the ECCS.
If such materials are specified at yield atrength levels greater than 90,000 psi, assurance of their compatibility with the reactor coolant will be provided.
The insulation used for the ECCS system will be compatible with the materials of construction. Details on this insulation will be discussed in the applicant's SAR.
i The chemistry of austenitic stainless steel is controlled for weld fabrication of ECCS components so that the predicted microstructure of the veld deposit eliminates the probability of microfissures.
Except for those weld metals that have demonstrated resistance to microfissures (e.g., AWS E16-8-2 and 4
similar composition wire), all austenitic stainless steel weld metals will have a minimum of 5% delta ferrite. content as required by the ASME. Code,Section III.
In addition to the code requirements, B&W specifies that austenitic stainless steel weld materials for ECCS components fall in the range of 5 to 20% delta ferrite when measured as required by the ASME Code,Section III, using mag-netic permeability test methods. Materials qualified as described above are.
16 1
acceptable as indicated by the revised NRC position on Regulatory Guide 1.31,
" Control of Stainless Steel Welding," dated 4/11/74 (MIEB 5-1).
l i
Production weld testing for delta ferrite measurement as indicated by provisions 3 and 4 of the NRC position dated 4/11/74 is not considered necessary to obtain satisfactory welds.
B&W test data from production welds justifies this position.
l 6.3.2.5.
Desian Pressures and Temperatures i
The design pressures and temperatures for all components in the ECCS are listed in Table 6.3-3 and shown in Figures 6.3-1, 6.3-2, and 9.3-1.
These design Pressures and temperatures are selected so that the equipment will function under anticipated accident conditions.
The LPI piping and components will be designed for normal reactor cooldown con-ditions since they are part of the DHRS. These normal pressure and temperature requirements are greater than those encountered during emergency operation.
The HPI piping and components are designed for normal operating conditions as part of the MU&PS. Although the RPI lines do not serve any function during, normal reactor operation, they are designed to normal makeup system conditions since the makeup system piping and valves encounter more severe conditions during ruarmal cperation thau during emergency operation.
i 6.3.2.6.
Coolant Quantity The quantity of coolant available in the core flood tanks (accumulators) is l
j given in Table 6.3-1.
The sizing criteria for the borated water storage tank j
is given in section 9.3.6.6.18.
l2 6.3.2.7.
Pump Characteristics I
eliminary pump characteristics, including total dynamic head, NPSH, l
l
_re shown in Figure 6.3-2 for the RFIS (makeup) and in Figure 6.3-3 for the j
LPIS (decay heat removal) pump.
t l
6.3-5 Babcock s,Wilcox.
4 e-v
--e.. - -
e-e v
L B-SAR-205 Amend. 16 122.9 (Regulatory Guide 1.31) Branch Technical Position MTEB 5-1 requires pro-duction testing of austenitic stainless steel welds to verify that ade-quate delta ferrite levels are present. Your response to request 122.4 is inadequate to justify no production testing. The following procedure is an acceptable alternative to production testing of austenitic stain-less steel welds:
Prior to production usage, the delta ferrite content of each lot and heat of weld filler metal procured should be verified for each process to be used in production. This delta ferrite verification should be made by determinations on undiluted weld deposits using magnetic mea-suring devices. For submerged are welding processes, the verification tests for each wire-flux combination may be made on a production veld.
All other delta ferrite measurements should be made on weld pads which will provide an undiluted layer of weld metal. The " Welding Research Council Recommended Procedure for Pad Preparation and Ferrite Measure-ment of Covered Electrode Deposits," is considered acceptable for use.
The undiluted weld deposit should show an average ferrite number from 5 to 20.
The upper limit of 20 may be waived for (a) welds that do not receive post-weld stress-relief heat treatment, or when su:h post-weld stress-relief treatment is conducted at temperatures below 900F, (b) welds that are given a solution annealing heat treatment, and (c) for single-pass welds that employ consummable inserts. It is our position that you should provide your commitment to the alternative procedure described or to BTP MTEB 5-1.
Response
The alternative to producting testing of austenitic stainless steel welds described in the second paragraph of this question is acceptable to B&W and 16 will be specified for Babcock-205 components in cases where production testing is not utilized. Section 4.2.2.1 has been revised accordingly.
l l
l 122.9-1 Babcock & )Milcox L
.