ML20053F084
| ML20053F084 | |
| Person / Time | |
|---|---|
| Issue date: | 05/24/1982 |
| From: | Norry P, Scott R NRC OFFICE OF ADMINISTRATION (ADM) |
| To: | |
| Shared Package | |
| ML20053F082 | List: |
| References | |
| NUDOCS 8206100418 | |
| Download: ML20053F084 (9) | |
Text
REQUEST FOR OMB REVIEW c
(Und:r tha P:perwork Reduction Act and Executive Ordar 12291) mp rt:nt - Read instructions (SF.83A) b3 fore completing this Offics o'information and R gulatory Aff airs orm. Sucmit tne requatednumber of copies of SF-83.together Offoce of Vanagement and Budget with th2 material for wrisch review is requested to:
Wa shin gton. D.C. 2o5o3
'. D;part~.e.t' Agency and Bureau / Office originating request
- 3. Name(s) and telephone number (s) of person (s) who can best answer questions regarding request U. S. Nuclear Regulatory Commission Robert Baer 492-4780 2.6-dic:t Agency / Bureau numcar (firstpart of 11-digit Treasury 4.3-digit f unctional code (last part of 11-digit Timury Account Account No )
No.)
_3
_1_
0
_2_
_0__
_Q._
_ 2 _Z_ _ 5_
). Tstia of intctmatson Collection or Rulemaksng C. ls this a rulemaking suomassoon under Section 35o4th) at Degradation of Threaded Fasteners in the P.L 96-517 ? (Chech one)
Reacter Coolant Pressure Boundary 19 No (Section 3507 submission)
Components of PWR Plants 2 0 Yes.NPRM. Expected date of purat om
- i. A.ls cnyinformation collection (reporting or recordkeeping) 3 0 Yes. final cule. Expected date uf pubhcaucn:
in volved? (Check one)
Etf ective dste 1 $ Yes and oroposal is attached for review D. At what phase of rulemakingis this submission made?
2 O Yes but prc00$3!is not attached - Skip to question D 3 O Ho - skip to ouestson D.
15 Not applicable B Ar2 the respondents pnmarily educationalagencies or 2 0 Maior rule.at HLRM stage institutions oris the purpose related to Federaleducation 3 0 Maior Final ru'e for which no NPRM was published programs ?
4 O Major Final rule. af ter publication of NPRM O "es d No 5 O Nonmajor rule, at NPRM stage 6 O Nonmajor rule, at Final stage COMPLETE SHADED PORTION IF INFORM ATION COLLECTION PROPOS AL IS ATTACHED
?. Current (or former) OMB Number
- 8. Requested
- 12. Agency report form number (s)
Expiration Date Expiration Date
- 13. Are respondents only Federalagencies?
y/A 5-30-f/
O Yes Dt No
). ls prc;csed information collection listed in
- 14. Type of request (Check one) th information collection budget?
O Yes
@ No 1 O prehminary plan Io Will this proposed nnformation collection 2 y new (not prevrously approvedor expired moie than 6 months
^
cause lhe agency to exceed its information ago) collection budget allowance? (11yes attach O Yes 00 No 3 0 revision amendment request from agency head) a C extension (aciustment to burden only) t 1.Numcer of report forms submitted for approva!
5 O extension (no cnangel N/A _
G D reinsta'ement (exp"ec "'thrn 6 months) l S.
- 16. Classification of Change in Burden (explain in supporting statement)
- 3. Appren a9a'e s le Ot un. vers: 6'sa c'e>
33 No.of Responses No of Reportmg Hours Cost to the Public a sin et se'
N/A
- a. in inventory S
c Eshmoin nutecer et b As proposed 22 1 320 s
r2 sooneems er 7
rIcord kUDers per year
))-
C. Dif ference (b-a) 22 1,320 s
9 me:rts a*eva, by eacn Explanation of difference (indicate as many as apply) respo,oer t Idem 251 2
Adjustments o Tets anau s h e sponses tasm 15:,,s ci d Correction-error i
i is gg
- e. Correction-reestimate i t Est. atida crase
-- l1 is eurerencu s
- 1. Change in use i
i ib perreu e sc 60 Program changes
- Estim
- .tre tets "ours e t r nnu si euroe m'
- g. Incre ase
+
22 1.320
+5 r,sc a mar ta;m 157, f 5r) 1,320
- h. Decrease
-s 8206100418 820524 PDR ORG EUSDMB Standard Form 83 (Rev. 3-81)
PDR For Use B*omning 4 /1/Q1
' 7. /.csua::-m::s and Uses (So words orless) inis inforr3 tion collection is imposed on Pressurized Water Reactor licensens to identify a possible ger.eric problem cssociated with the degradation of threaded fasteners (bolts and studs) in closures in the reactor coolant pressure bouWy.
i E. R:; tate: resort f armts) (gtwe OMB number (s),IRCt/(s/,
2o. Catalog of Feceral Domestic Assistance Program Nurnber ontarnst a gency report form number (s) or symbol (s))
N/A
- 21. Small business or organization O Yes
'iil No M
19 Tpe of affected pubhc (Check as manyas apply)
- 22. Type cf activity of affected public-indicate 3-digit Standarg industrial Classification (SIC) code (s) (up to 10) - it over
- O individuals or households
- 10. check O Muttiple or O All 2 O state orloc.elgovernments 3 O larms 4 Q businesses or otherinstitutions (except forms) 4E 3
=
23.Bri t descriptson of affected public (e g.."retailgrocery stores."" State education agencies."" households in 50 largest SMSAs")
Pressurized water reactor facilities holding an operating license.
64 Fu'o:se ' Check as many as apply Ilmore than one. ondicate
- 26. Collection method (Check as many as apply) preccm:nant by an asterisk) 3 g mail self. administered 1 O aopt. cation for benef;ts 2 O other self-administered 2 O prg'am evaluation 30 telephcneinterview 3 O ge"eral purpose statistics 4 O personalinterview 4 O re;u'atory or compliance 50 recordkeeping requirement:
5 O preg am planning or management Required retention period:
years 6 0 resea ch 25 Fre:;ency of Use 6 O other-describe:
- 27. Co!!ection agent (Check one) 1 E Norrecurre.g 1 O( requesting Cepartment/ Agency Rec. ring icheck as many as apply) 2 O other Federal Department / Agency 2 O On occasion 6 O semiannually 3 O private contractor 3 0 weekly 7 0 annually 4 O recordkeeping requirement 4 0 monthly 80 biennially 5 O other-describes 5 0 cuarterly 90 other-describe:
28' Autner iy fc! agency for information collection or
- 30. Do you promise confidentiality?
rulema Mng-indicate statute. regulation,juicial decree.
(1/ yes, explain basis for pledge etc in supporting statement )
D Yes q No Atomic Energy Act of 1954 l 31.will the proposed information collection create a new or become part of an existing Privacy Act system of records?
25 Res:cecsnt's co:igation to repiy (Check as many as apply)
(Il yes. atta ch Federal Register notice or proposec dratt of 1 O voturtary not#ce.)
O Yes XI No 2 O recu ed to obtain er retain benefit i
- 32. Cost to Fede a Government of 3 Q(mancatory-cite statute, not CFR (attach copy of information conection or rulemaking S 42.41C statutory authority)
Atomic Eneroy Act, 1954 COMPLETE ITEMS 33 THRU 35 ONLY IF RULEM AKING SUBMISSION 33 Compliance costs to the pubuc
' 34 is there a regulatory impact
- 36. ls there a statutory or judicial analysis attached?
deadhne affectmg issuance ?
S I
O Yes O No O Yes. Enter date:
O No CEOTIFIC ATioN BY AUTHORIZED OFFICI ALS SUBMITTING REQUEST-We certity that the information collection or rutemaking submitted for r;v.:* is ne:essary for the pec:= pe formance of tne agency's f unctions.that the prepesai represents the minimum public Durden and Federat cost cens. stem ac eec anc is cc s stent etn apphcaole OMB and agency policy d.rectives signature and title of.
osa:m s:. :. : r ciat r a acts:v caTE sueuiTT WG or m at DCE J.
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r-m n Patricia G. Norry R.* Stephen Scott
a 4
Supporting Statement for IE Bulletin on Degradation of Threaded Fasteners in the Reactor Coolant Pressure Boundary Components of PWR Plants Justification As described in the section of IE Bulletin entitled " Description of Circumstances,"
there have been a number of instances of severely degraded fasteners (bolts and studs) in the reactor coolant pressure boundary of pressurized water reactors.
The safety concern is that degradation and failure of these bolts and studs could result in loss of integrity of the reactor coolant pressure boundary, and in an extreme case a loss of coolant accident could occur.
Currently applicable ASME Code Section XI rules do not require in-service inspection of bolts and studs in sizes two inches or less in diameter. Most failures have occurred in fasteners of this size or smaller.
Therefore,.the NRC is requiring the licensees of pressurized water reactors to perform additional inspections during the next refueling outage scheduled 60 days after issuance of the IE Bulletin.
The licensees are to submit reports regarding the results of their inspections and past usage of seal nts 3
and lubricants that are believed to be contributors to the problem of fastener degradation.
The reporting requirements are specified in the bulletin.
There is no other source for the data.
Description of Survey Plan A total of 31 pressurized water nuclear power plant licensees are required to respond. The response is to cover 47 individual units located at 33 sites.
The respondents are the licensees of pressurized water reactors.
Tabulation and Publication Plans There are no current plans for publication of the data obtained.
- Time Schedule for Data Collection and Publication The time schedule as outlined in the bulletin requires that respondents must provide an initial response within 60 days; as well as results of inspections within 60 days after they are completed.
There are no plans to publish the results.
NRC will make an immediate review of the data for technical adequacy and completeness.
Follow-up field inspections will be made and other actions taken, as appropriate.
Estimate of Respondent, Reporting Burden Each licensee is required to submit reports as specified in the bulletin.
One report deals with a leakage previously experienced and a survey of thread lubricants and it.jection sealant applications.
The other report is to confirm that appropriate procedures exist or have been prepared and provide results of examination of threaded fasteners performed during the scheduled outage.
It is estimated that preparation of the two reports will take 120 person-hours per site. Therefore, the total respondent burden is estimated to be approximately 1,320 hours0.0037 days <br />0.0889 hours <br />5.291005e-4 weeks <br />1.2176e-4 months <br /> (11 sites per year x120 hours), a one time burden.
Estimate of Cost to Federal' Government Preparation of the bulletin, including obtaining all of the necessary clearances, requires about 3 person-weeks of effort.
It is estimated that about 1/2 person-week of review effort will be required for each of the 47 nuclear units for a total of 23.5 person-weeks of review effort.
There fore, the total Government effort is estimated to be 26.5 person-weeks.
(1,060 hours6.944444e-4 days <br />0.0167 hours <br />9.920635e-5 weeks <br />2.283e-5 months <br /> x $40 = $42.4K - total estimated cost)
SSINS No.:
6820 IEB 82-t UtlITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C.
20555 May
, 1982 IE >U'.LETIN N0. 82-DEGRADATION OF THREADED FASTENERS IN THE REACTOR COOLANT PRESSURE B0UNDARY OF PWR PLANTS Addressees:
All pressurized water nuclear power reactor facilities holding an operating license (0L), for action.
All oth'er nuclear power reactor facilities holding an cperating license or construction permit (CP), for infonnation.
Purpose:
The purpc.e of this bulletin is to:
(1) notify licensees and construction pernit honders about incidents of severe degradation of threaded fasteners (bolts and studs) in closures in the reactor coolant pressure boundary (RCPB),
and (2) to require appropriate actions.
A response to this bulletin is required from prescurized-water reactors (PWRs) holding an operating license as discussed belcw.
Desc.-iotion of Circumstances:
In May 1980, Omaha Public Power District (0 PPD) submitted a special maint-enance report to the NRC about the significant corrosion wastage experienced with closure studs in the reactor coolant pumps at its Fort Calhoun facility.
The corrosion wastage was attributed to boric acid attack as a result of leakage at flexitallic gasketed joints between the pump casing and pump cover.
These closure studs are 3.5 inches in diameter, and are manufactured of SA 193-B7 (A'SI 4140) low-alloy, high-strength steel.
Accordingly, the NRC issued Information Notice 80-27 on June 11, 1980 to all PWR licensees about the potential for undetccted boric acid corrosion wastage and emphasized the need for supplemental visual inspection of pressure retaining bolting in pump and-valve components.
Subsequently, similar occurrences of corrosion wastage frorn borated water leakage have been identified at other PWR plants, as discussed belcw.
On March 10, 1982, the NRC was notified by Maine Yankee Atomic Power Company and Ccmbustion Engineering (C-E) that during routine disassembly of a steam generator primary manway at Maine Yankee, 6 of the 20 manway closure studs failed and another 5 were found to be cracked by ultrasonic examination using specialized techniques.
Leakage had been noted from this manway during the current operating cycle and several efforts were made to eliminate the leakage.
These efforts involved increasing the joint operatirig compression through torquing the studs to hydrotest levels and repeatedly injecting Furmanite sealant.
Normal plant operation continued until a planned maintenance outago.
IEB 82-May
,1982 i
Page 2 of Preliminary results of a metallurgical analysis C-E performed on the affected stucs has indicated that the failure mode was stress-corrosion cracking (SCC).
By Information Notice 82-06 (March 12, 1982), IE notified all licensees and construction permit holders about this degradation to emphasize the increased vtential for studs to fail by the joint action of stud preload, materiti conditions and a corrosive environment generated by the presence of primary coolant leakage.
As a followup to the information notice, the utility established that the root cause of leakage was due to an interference contact between the gasket retainer lip and vessel cladding which prevented proper compression of the flexitallic gasket during reinstallation of the manway cover.
This problem was corrected and all 20 studs were replaced.
Magnetic particle and ultrasonic examinations of the studs in manways of the other two steam generators identified no other failures.
In the last several years a significant number of incidents have been reported of bolts and studs that have failed or become severely degraded because of bric acid corrosion wastage or SCC mechanisas.
Preliminary results of an NRC s aff review of threaded fastener experience in operating nuclear power plants h.s identified that specific generic actions need to be taken before the study is ccmplete.
The staff review identified 44 incidents of threaded fastener degradation since 1964.
From Table 1 it can be seen tnat since 1977, 15 incidents related to primary coolant pressure boundary application have been recorded.
These incidents involved 9 P,WR plants and that 5 of those plants experienced repeated problems.
Of concern is that degradation and failure of such threaded fasteners constitute a potential loss of RCPB integrity and, in the extreme case, a LOCA could occur should extensive fastener failures in a pressuie retaining closure not be detected.
In some instances it has been reported that Furmanite, a form of sealant compound, has been injected into bolted closures in the RCPB as a means of convenient maintenance to control leakage.
A review of the limited chemical analysis available on Furmanite indicates it has a variable composition with respect to concentration of chlorine, fluorine, and sulfur which are leachable and well recognized promoters of SCC.
Consequently, prolonged exposure of the sealant to leakage and high temperature conditions causing a gradual release of its potentially corrosive ions must be taken into account.
Also, certain lubricants may be formulated with molybdenum disulfide (flos )
whi h contains a significant level of sulfide constituent.
Experience suggests that.MoS has a pronounced tendency to decompose in the presence of high temperature and moisture conditions to release sulfide which is a known contaminant causing SCC failures and cannot be ruled out.
Therefore, care should be exercised in the selection and application of lubri-cants, and injection sealants to minimize the risk of SCC from potentially corrosive ions due to the gradual breakdown and/or synergistic interaction of such materials with prolonged exposure to leakage conditions.
This would be of
F IEB 82-April
, 1982 Page 3 of particular concern for fastener materials made of high strength low alloy steels and, austenitic and martensitic stainless steels (i.e., 304, 316, 415, 17-4 PH, etc.) which are known to be susceptible to halogen / sulfide SCC degrada-tion.
The above concerns are further compounded by the fact that under the present ASME Code Section XI inservice inspection rules ultrasonic examination is not required on threaded fasteners in sizes 2-inches and less in diameter (e.g.,
Table IWB-2500-1).
However, except for the reactor coolant pump stud wastage, most failures have occurred in fastener sizes 2 inches and smaller.
Furthermore, experience has clearly shown that code specified UT examination methods is not singularly adequate to detect corrosion wastage conditions.
Moreover, the present code UT procedures are not sufficiently sensitive to, detect initiation of stress corrosion cracking (SCC) but requires the use of specialized UT techniques and calibration standards based on notch reflectors simulating critical flaw parameters to enhance reliability of detection.
At the present time, visual examination (e.g., IWA 2210, VT-1) appears to be the only method to detect borated water corrosion wastage or erosion-corrosion damage and may require insulation removal and/or disassembly of the component in some cases, in order to have direct visual access to the threaded fasteners.
Therefore, degradation could go undetected when there is no clear evidence of leakage in the surrounding area.
Similarly, the reliability of visual examination alone is questionable in detection of SCC initiation of threaded fasteners either in-situ or removed.
Accordingly, it is necessary that a combinction of nondestructive examination techniques (UT,VT-1, MT) be employed to the maximum extent practical to enhance detection of the degradation mechanisms discussed above.
Actions To Be Taken by PWR Facilities Holding Operating Licenses:
The scope of action items listed below are to include the threaded fasteners (studs or bolts) in steam generator and pressurizer manway closures, valve bonnets and pump flange connections, installed on six-inch lines nominal diameter and greater that form a part of the reactor coolant pressure boundary (RCPB).
Also included are control rod drive (CRD) flange and pressurizer heater connections tnat do not have seal welds to provide leak-tight integrity (e.g., CRD's having an omega seal weld design are excluded from this bulletin a cti on )'e.
The reactor vessel head closure studs are excluded for those PWR license s committed to the provisions of Regulatory Guide 1.65, " Materials and Inspection for Reactor Vessel Closure Studs."
Action Item 1 is to be completed prior to the performance of the subsequent action items.
Action 2 is to be performed within the next cycle but no later than the completion of the next refueling outage that is initiated after 60 days from the date of this bulletin.
The report requested by Action 3 is to be submitted within 6F days from the date of this bulletin.
1, Where procedures do not exist, develop and implement maintenance procedures for threaded fastener practices.
Those procedures should
IEB 82-May
, 1982 i
Page 4 of include, but not limited, to the following: (1) maintenance crew training of proper bolting / stud practices, tools application, specifications and requirements, (2) detensioning and retensioning practices, (torque iteration), specified tolerances and other controls for disassembly and reassembly of component closure / seal connections, (3) gasket installation and controls, and (4) retensioning methods and controls to elininate reactive coolant leakage during operations.
Quality assurance measures should also be established for proper selection, procurement and application of fastener lubricants and injection sealant compounds to minimize fasterner susceptibility to SCC environments.
2.
Threaded fasteners of closure connections, identified in the scope of this bulletin, when opened for component inspection or maintenance shall be removed *, cleaned and inspected per IWA-2210 and IWA-2220 of ASME Code Section XI (1974 edition or later) before being reused.
3.
NRC Information Notices 80-27 and 82-06, and similar INP0 correspondence with recommendations, have been issued in regard to corrosion problems associated with bolt / stud in RCPB closures.
To assist the NRC ongoing review and assessment of the scope of the problem it is requested that the following information be provi.ded:
(a)
Identify those bolted closures of the RCPB which have experienced leakage, particularly those locations where leakage occurred during the most recent plant operating cycle.
Describe the inspections made and corrective measures taken to eliminate the problem.
If the leakage was attributed to gasket failure or its design so indicate, and (b)
Identify those Class 1 components, if any, where fastener lubricants and injection sealant materials have been or are being used and plant experience with their application.
Include types and composition of materials used.
4.
A written report signed under oath or affirmation under provisions of Section 182a, Atomic Energy Act of 1954, shall be submitted to the Regional Administrator of the appropriate NRC Regional office within 60 days following the completion of the outage during which Action Item 2 was performed.
The report is to include:
1 A statement that Action Item 1 was completed.
c Fasteners " seized" or designed with interference fit, may be inspected in place.
I
IEB 82-May
, 1982 i
Page 5 of b.
Identification of the specific connectiuns examined as required by Action Item 2.
c.
The results of the examinations performe d (i.e. removed or in-situ) on the threaded fasteners as required by Action Item 2.
If no degradation was observed for a particular connection, a statement to that effect and identification of the connection is all that is required.
If degradation was observed, the report should provide detailed information.
5.
A written report signed under oath or affirmation under provisions of Section 182a, Atomic Energy Act of 1954, shall be submitted to the Regional Administrator of the' appropriate NRC Regional office within 60 days of the date of this bull' tin.
The report is to provide the e
information requested by Action Item 3.
Pctential oersonnel occupational exposure as a result of the above requirements should be considered in the program formulation process in an effort to main-tain incurred exposures ALARA.
Personnel exposure-savings techniques such as use of steam generator primary manway cover handling fixtures can provide substantial time and man-rem savings.
This request for information was approved by OMB under clearance number:
3150-00XX.
Comments on burder, and duplication should be directed to the Office of Management and Budget, Reports Management, Room 3208, New Executive Office Building, Washington, D.C.
20503.
If you have any questions regarding this matter, please contact the Regional Administrator of the appropriate NRC Regional office, or this office.
Sincerely, Richard C. DeYoung, Director Office of Inspection and Enforcement Techn.ical
Contact:
W. J. Collins 301-492-7275 Attachments:
1.
Table 1 2.
Previously Issued IE Bulletins e
,