ML20091L555
| ML20091L555 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 04/11/1984 |
| From: | Woolever E DUQUESNE LIGHT CO. |
| To: | Starostecki R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| Shared Package | |
| ML20091L547 | List: |
| References | |
| 2NRC-4-039, 2NRC-4-39, NUDOCS 8406080106 | |
| Download: ML20091L555 (5) | |
Text
e 2NRC-4-039 (412)787 - 5141 Telecopy 8
Nuclear Construction Division April 11, 1984 Robinson Plaza, Building 2, Suite 210 Pittsburgh, PA 15205 United States Nuclear Regulatory Commission Region I 631 Park Avenue King of Prussia, PA 19406 ATTENTION:
Mr. Richard W. Starostecki Division of Project and Resident Programs
SUBJECT:
Beaver Valley Power Station - Unit No. 2 Docket No. 50-412 USNRC IE Inspection Report No. 50-412/83-11 Supplement Report No. II Gentlemen:
This le t ter provides additional info rmat ion rela t ive to our previous responses to the subject inspection report.
In our res pons e da ted Octobe r 7, 1983 (Reference 4), unde r the heading " Corrective Act ion to Prevent Further Violations" DIE committed to four steps which have been completed.
1.
A Beaver Valley Power Station, Unit 2 (BVPS-2), Inspect ion and Enforcement Pos it ion rela tive to the ident ifica tion of ASME Code Editions in the FS AR has been made availab le to Mr. G.
Walton, the NRC Senior Res ident Ins pe ct o r.
This po s ition addres ses both the conce rns of Inspection Report 50-412/83-07 (Unresolved Item 02) and the concern of the subject ins pect ion.
2.
Power Piping Company (PPCo) has revised heat treatme nt proce-dure N-1141-P-8, Revision 1,
to comply with the cur rent requirements of specification 2BVS-58.
- 3. 'PPCo has repo rt ed that all its fab ric at ion, examinat ion, and testing procedures are in compliance with 2BVS-58 requirements.
4.
'A furnace survey was pe rfo rmed in accordance with PPCo Proce-
)
dure SFT-1, Revision 0.
The res ult s indicate that a maximum i
variance of 75*F in the furnace working zone at the 1100*F to 1200*F soaking temperature range was ach ieved.
This degree of temperature unifo rmity provides suf ficient assurance that the numbe r of recording thermocouples used was accep t ab le to control PWHT for piping spools.
8406080106 840601 gDRADOCK 05000412 PDR
United St&tes Nuclear Regulatory Commission Mr. Richard W. Starostecki Page 2-As indicated in our previous responses (References 4 and 5) a total of 35 ASME III pipe spools were ident ified as having been PWHT in accor-
' dance with PPCo Procedure N-1141-P-8, Revision 1.
The determination of maximum heating and cooling races required for heat treating by ASME III NB-4624 was based upon the nominal thicknes s for standard pipe sizes and the specified minimum wall thicknes s fo r s pe ci al size pipe butt welds between equal thickness weld end preparations. Special wall pipe was ordered to satisfy minimum wall requirements based on system pressure, tempe ra tue, high energy pipe break condit ions, and workmanship allowances.
The use of the exact maximum thicknes s of the weld or base materials is not conside red to be required by the code.
The heating and cooling rate control was required above 800*F in accordance with NB-4624, Winter 1973 Addenda, which was adopt ed fo r BVPS-2 in li eu of the 600*F control t empe rature required by the originally specified 19 71 Edi t io n,
Winter 1972 Addenda.
Using the above bases, PPCo and their ANI have recertified 29 of the 35 ASME III s pools which were heat treated under N-1141-P-8.
The remaining spools include three butt-welded relief valve heade rs and three spools with built-up weld ends which will require final PWHT in the field.
' Prior heat treatment of these remaining spools will be considered as int e r-mediate PWHT meeting the requirements of NB-4630.
The field PWHT of the three spools with built-up but t weld ends will be included in PWHT of the field butt welds.
Th is will require an increased PWHT band width of 2 inches beyond the weld build-up to enaure compliance with NB-4626.3.
The nonconforming welds on the three relief valve headers will be reheat treated as a unit to minimize tempe rature gradient s through the header assembly.
The two headers with acceptable relief valve nozzle butt welds wil1~ have these welds documented as receiving an ad dit ional PWHT cycle to ensure compliance with the rules for cumulative time at t empe ra-ture of NB-2400 and NB-4300.
PWHT performed by PPCo on these six spools is ac cept ab le in accor-dance with ASME ~III NB-4630 (intermediate PWHT).
Magnet ic pa rt ic le exami-nation - (MT) of these welds is not required since the actual heating and cooling rates were le s s than 600*F per hour _ divided by half _ the maximum (i.e., the specified) thicknes s' of the material in inches at the weld and in no case in excess of 600*F per hour' at temperatures above 600* F.
To ensure ' acceptable heating and cooling rates, the field will use the maximum recorded thicknes s from the weld end preparation minimum wall i
verification data given in the weld docume nt at io n package fo r ASME III PWHT.
i j
f
United States Nuclear Regulatory Commission
- Mr. Richard W. Starostecki
.Page 3 The base met al and weld repairs made on spool Nos. MS S-4 3-3 and MSS-43-6 using 175'F preheat without final PWHT are acceptable.
The base materials have report ed carbon cont ent s -les s than 0.30 percent and, as such, are exempt from PWHT without preheat in ac cordance with ASME III Table NB-4623.1-2, Winter 1973.
The intent of 2BVS-58 to require a 200*F preheat ' for all P-1 material in excess of 3/4 inches was to avoid potential 7
nonconformances due to material carbon content dif ferences and to s imult a-
-neously satisfy ANSI B31.1 and ASME III preheat rules for exempting PWHT.
Document ation fo r MS S-4 3-2 h as be en rev ised to refe rence an approved procedure. qualified with the came es sent ial variables but including PWHT for shop weld "A".
PPCo Welding Procedures 1021 and 1042 were revised to pe rmit PWHT t empe ratures between 1100* F and 1250*F which is ac cept ab le in accordance with ASME III Table NB-4623.1-1.
Requalification of these welding proce-dures was not required in accordance with ASME Interpretation No. IX-79-13.
l Spool No MSS-043-6 is acceptable on this basis.
PPCo ' documentation has been revised to reflect the above-ment ioned corrections ~ ~ and. will be forwarded to BVPS-2 for ac cep tance.
The NPP-1 forms fo r the 29 ac cept ab ly he at-treated spools have be en revised to include a reference to ASME III NB-4620, Winter 1973, for PWHT.
A recent NRC letter, dated March 30, 1984, que s t ions the bases for determining thicknes ses used for controlling PWHT time at tempe rature and j
heating / cooling' rates. An additional review will be performed to determine l-that the ordered (i.e., the specified minimum) wall thickness, is represen-L tative.of the actual butt weld end prep thicknesses of the 28 spools fab ri-j' cated with special size pipe.
The results of the review will be used to determine the acceptability of using the-specified pipe wall thickness fo r i
controlling PWHT time at temperature and heating / cooling rates.
Completion of this evaluat ion is expect ed by June 1, 1984.. The results - of - the evaluation will ~ be provided to the NRC Senior Resident j.
. Inspector for review.-
I DUQUESNE LIGHT COMPANY V
y By:
E.1/. Woolever Vice President
- SUBSCRIBED AND SWORN TO BEFORE ME.THIS g -DAY OF d
, 1984.
f Ifl i / L 0 b e Notary Public
. ANITA EI.AINE REITER, NOTARY PUDLIC ROBINSON TOWNSHIP, ALLEGHENY COUNTY.
p MY COMMISSION EXPIRES OCTOBER 20,1986 -
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United States Nuclear Reguistory Commission Mr.- Richard W. Staro.stecki Page 4 RW/wjs cc:
Mr. G. Walton, NRC Resident Inspector Mr. M. Lacitra, Project Manager NRC Document Control Desk 1
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REFERENCES:
- 1) NRC letter Docket No. 50-412, dated September 9,1983 l
- 2) NRC letter Docket No. 50-412, dated January 4,1984
- 3) NRC letter Docket No. 50-412, dated March 30, 1984
- 4) Duquesne Light Company letter 2NRC-3-075, dated October 7, 1983
- 5) Duquesne Light Company letter 2NRC-4-021, da ted March 1,
1984
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Unitcd Stacco Nuclear Rigulatory Commission Mr. Richard W. Staroatecki-Page'5 l
l COMMONWEALTH OF PENNSYLVANIA )
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SS:
COUNTY OF ALLEGHENY
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On this'
//M c' 2y of Losc)
((
, before me, I
a Notary Public in and fo r said Commonwealth and County, pe rs onally appeared E. J. Woolever, who being duly sworn, deposed and said that (1) he is Vice President of Duquesne Light, (2) he is duly authorized to execut e and file the foregoing Submittal on behalf of said Company, and (3) the statements set forth in the Submittal are true and correct to the test of his knowledge.
Ltch E A-
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ANITA ELAINE REITER, N TAlf[Pb0kih" ROBINGON TOWNSlit?, ALLEGSENY COUNTY MY COMMISS!ON EXPI'iES OCT03?R 20,1986 k'.