ML20063P459
| ML20063P459 | |
| Person / Time | |
|---|---|
| Site: | Washington Public Power Supply System |
| Issue date: | 09/30/1982 |
| From: | Root R WASHINGTON PUBLIC POWER SUPPLY SYSTEM |
| To: | Sternberg D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| Shared Package | |
| ML20063P450 | List: |
| References | |
| GO1-82-0578, GO1-82-578, NUDOCS 8210130425 | |
| Download: ML20063P459 (5) | |
Text
- -
' D WashinSton Public Power Supply System g, ,
P.O. Box 968 3000GeorgeWashingtonWay flichland, Washington 99352 (509)372-50007;.
D'p _
Docket Nos. 50-460 & 50-513 O ,,i.
September 30, 1982 G01-82-0578 Nuclear Regulatory Commission Region V 1450 Maria Lane, Suite 210 Walnut Creek, California 94596 Attention: D. M. Sternberg, Chief Reactor Construction Projects Branch No. 1
Subject:
NUCLEAR PROJECTS NOS.1 & 4 NRC INSPECTION WNP-1/4 DATES OF INSPECTION APRIL l-30, 1982 CONSTRUCTION PERMIT NOS. CPPR-134, CPPR-174
Reference:
- 1) Ltr. T.W. Bishop to R.W. Root, dated June 8, 1982, NRC Inspection at WNP-1/4 Site
- 2) Ltr, G01-82-0549, dated September 9, 1982, same subject Reference one (1) above delineates the results of the April 1-30, 1982 inspection of activities authorized by NRC Construction Permit Nos.
CPPR-134/174. Reference two (2) above provided an interim response to the Notice of Violation which was enclosed as Appendix A.
The purpose of this letter is to provide you with an update on the corrective actions being taken in regard to Finding a. and to provide you with the disposition of the CNCR's associated with Finding b. of your report. Also included are the actions being taken in regards to paragraph 12.d. of reference one (1) which was inadvertently omitted from our original response.
As was noted in reference two (2), local grinding to expose weld root and base metal surfaces as well as acid etch to identify the weld deposit and joint configuration was performed on four welds on pipe rupture restraint MS.i-PW-3-2.
l Inspection shows the cause of undersized partial penetration welds to be improperly prepared weld bevels rather than lack of penetration.
The specified bevel was 3/4 inch whereas examination of the weld joint indicated the fabricated bevel ranged from 9/16 inch to 25/32 inch on four welds making up a fabricated member of the restraint.
~^
l [8210130425'821006~ ,
l t PDR ADOCK 05000460 PDR l '. _ Q .
l
c.
STATE OF WASHINGTON COUNTY OF'BENTON .)
R. W. Root, being first' duly sworn, deposes and says: That he'is the Acting Program Director, WNP-1/4, for the WASHINGTON PUBLIC POWER _ SUPPLY.
SYSTEM, the applicant herein; that he is authorized to submit the fore-going on behalf of said applicant; that he has read the foregoing and.
knows the contents thereof; and believes the same to be true to the best of his . knowledge.
-DATED J Q Q,d , 1982
) /,
R.3 I
On this day personally ahpeardd before me R. W. ROOT to me known' t'o be the individual who executed the foregoing instrument and acknowledged that he signed the same as his free a'c t and deed for the uses and pur-poses therein mentioned.
y'* % h r #
- 'N
~'
GIhEN u' n der my hand and sea 1 'th'is $o day oh & M a J v i , 1982 v
-g kah Notary Public gand f(r)the State of Washington Residing at % cath
l D..M. Sternberg i Page 2 !
G01-82-0578 l
Design calculations for MSS-PW-3-2 have been reviewed. The design throat dimension of the subject welds is governed by secondary forces ;
transmitted to the restraint during a postulated pipe rupture. Primary jet reaction forces are directed toward a crush pad. Impact is'between the pad and a bumper which is attached to the pipe by U-bolts.
Secondary forces are generated on a cantilevered member of the restraint which guides the bumper to the crush pad. The secondary force of 1000 Kips is in a direction normal to the primary reaction !
force of 1400 Kips. l l
The original design of the restraint conservatively assumed the secondary guiding forces at 70% of the primary force. This is 1 consistent with the design assumptions used with other restraints which place the secondary force in the range of 50-70%. However, a detailed analysis has been performed for - MSS-PW-3-2 secondary forces using a simultaneous equilibrium equation technique. This method was not included in the original design calculations. This analysis, which more accurately determines secondary forces at 55% of the primary force, has been incorporated into the design basis for the restraint.
The new design basis remains conservative.
Weld sizing based on the revised design basis shows that the subject partial penetration welds are required to have a 3/8 inch throat.
Accordingly, the as-fabricated welds are in excess of this requirement; therefore, the pipe rupture restraint will perform its function. The apparent undersize weld, which was documented on Nonconformance Report 1-BNCR-151-02 will be dispositioned "Use-As-Is".
Pipe rupture restraint MSS-PW-3-2 was supplied by our contract 151. We have examined the design of 123 other restraints also fabricated by this contractor and have identified approximately 70 partial penetrat-ion welds on 22 restraints. These welds require the same type of bevel preparation as the four subject welds on MSS-PW-3-2, although they are not necessarily the exact type of preparation (3/4 inch 45 degree bevel on 1-1/2 inch plate). . Partial penetration welds make up approximately 1% of the total welds on all restraints. Fillet welds are most common and full penetration welds are more numerous than partial penetration welds.
We will examine approximately 20% of the partial penetration welds to determine if under sized beveling by the fabrication contractor on MSS-PW-3-2 was an isolated incident or generic to other restraints.
The investigation will be accomplished by grinding paint and the return weld passes from the restraint member ends, performing an acid etch and measuring actual bevel dimensions. If found to be a generic nonconformance to drawing specification requirements, an expanded examination program will be developed and implemented. The work will be performed after restart of construction.
D.M. Starnberg Page 3 G01-82-0578 The Supply System will include this item in the Project follow-up status listing of commitments requiring action upon resumption of construction activities. The results of this examination will be reported to the NRC within two months following completion of the work.
The report will include details of additional examinations determined necessary by the Engineer.
ismer &
As was(FWB)
Becker notedhadin our original written response contractor to Finding b.,
nonconfomance Foley-W(CNCR's) reports 1-CNCR-218-1100 & 1110 and submitted them to the Engineers for disposition. At the time of our report, these CNCR's had not been dispositioned by the Engineer; however, they have subsequently been dispositioned to rework the Quality Control Instruction (QCI) to be in compliance with the requirements of the Quality Control Procedure (QCP) and to use-as-is the existing documentation of conduit supports installed between December, 1981 and April, 1982.
- In response to your June 8, 1982 letter, the following actions are being taken to resolve the NRC item (80-03-01) related to the protection of stainless steel piping from external contamination.
The CM0 (Bechtel Power Corporation) has taken samples of the bird droppings and had an analysis perfomed on them to detemine the content of chlorides and fluorides. The CM0 is in the process of obtaining test result:, for the aircraft cleaner-solvent used by the electrical contractor. These test results will be submitted to the Engineer (United Engineers & Constructors) for detemination of acceptability. Acceptability will be based on acceptance criteria established by the Engineer. Additional corrective action for these materials will be initiated based on the Engineer's determination.
The contract specifications will be revised to contain a material restrictions section which prohibits the use of material containing or compounded from chlorides, fluorides, halide or mercury from being part of pemanent plant material and/or equipment which comes in contact with stainless steel or being used in such a way as it could become part of the material / equipment which comes in contact with stainless steel. This material restrictions section will also include requirements to control construction materials utilized during certain l
stages of construction which.present particular hazards to stainless steel, to preclude inadvertant contamination of the stainless steel during their use.
Contractors procedures will be revised and subsequently reviewed by the Engineer to assure compliance with this material restriction requirement.
D.M. Sternberg Page 4 G01-82-0578 The specification revisions and procedure revisions will be completed prior to May 1, 1983.
R. W. Root, Acting Program Director (821)
RWR/CRE/pp cc: V. Stello, Director of Inspection, NRC A. Toth, NRC (81'1 J.D. Bateman, UL/ (895)
J.P.Laspa,Bechtsi(861)
V. Mani , UE&C (89~>)
Attachment