ML20093E130

Provides Steps to Be Taken to Correct 820802 Response to IE Bulletin 82-02,Item 5.Info Documenting Util Compliance W/Reg Guide 1.65 Re Reactor Vessel Studs Encl

ML20093E130
Person / Time
Site:	Fort Calhoun
Issue date:	07/02/1984
From:	Andrews R OMAHA PUBLIC POWER DISTRICT
To:	Jay Collins NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
IEB-82-02, IEB-82-2, LIC-84-209, NUDOCS 8407170383
Download: ML20093E130 (9)

Text

i .

Omaha Public Power District 1623 Harney Omaha, Nebraska 68102 402/536 4000 July 2, 1984 LIC-84-209

=__

p- is u N b Mr. J. T. Collins, Administrator I U. S. Nuclear Regulatory Commission Region IV JUL 10 584 611 Ryan Plaza Drive, Suite 1000 , 3/

Arlington, Texas 76011

References:

(1) Docket No. 50-285 (2) IE Bulletin 82-02 (3) Letter from W. C. Jones to J. T. Collins dated August 2, 1982 (LIC-82-269)

Dear Mr. Collins:

IE Bulletin 82-02 In a letter dated August 2, 1982, the District provided its re-sponse to Item 5 of IE Bulletin 82-02. IE Bulletin 82-02, Item 5, requested, in part, that licensees " identify those closures and connections, if any, where fastener lubricants and injection-sealant materials have been or are being used and report on plant experience with these applications, particularly any instances of SCC of fasteners. Include types and composition of materials used." The D3 strict's response to Item 5 stated, in part, that "The Port Calhoun Station approved maintenance procedures call for the use of NEVERSEIZE PURE NICKEL #65 on all threaded fasteners.

To date, the District has experienced no problems related to use.

of NEVERSEIZE LUBRICANT." This letter provides the steps to be l taken to correct the District's response relating to Item 5.

l During the week of May 7-11, 1984, IE Inspectors conducted an in-l spection relating to the District's response to IE Bulletin 82-02.

l l

As a restit of IE Inspection No. 84-12, it was brought to the Dis-trict's attention that the response to IE Bulletin 82-02, Item 5, was not complete. When the District became aware that its re-sponse was not complete, steps were immediately taken to conduct a reinvestigation in order to gather sufficient information to en-able the District to provide ar update to the response to IE Bulle-tin 82-02, Item 5. Iloweve r, two factors have delayed our update to the response. First, on May 16, 1984, the Fort Calhoun Station experienced a steam generator tube failure. Following this fail-ure, all available rescurces were devoted to correcting and ro-solving issues relating to the steam generator tute failure, in-c2nding preparation of reports to the Commission, preparation for meetings with the Commission, implementation of corrective actions, submittal of reports, und preparation of responses to the cs suo 8407170383 840702 PDR ADOCK 05000285 yment wim Equal Opponunity G PDR Male / Female /

5 Mr. J. T. Collins LIC-84-209 Page Two Commission's June 5, 1984 letter. Second, the preparation of a re-vised response was underway when the person developing the revised response encountered medical problems which required his hospitali-zation for an extended period of time.. The individual is still under medical care at this time. The activities associated with the steam generator tube failure, coupled with the unavailability of a key person who was involved in the initial preparation of the District's response to IE Bulletin 82-02, delayed the completion of a revised response to the bulletin.

The following represents an overview of the procedures and prac-tices that were in place at the time the response to IE Bulletin 82-02, Item 5, was prepared and how the response was handled in accordance with those procedures and practices.

Correspondence to and from the Commission is handled in accordance with Licensing Procedure DAS-L-03. This procedure calls for a re-

! view of incoming correspondence.from the Commission by the Licen-sing Administrator to determine what action, if any, is required by the District. If action is required, then assignments are made (including due dates) to the appropriate department to ensure that the required action will be adequately addressed in a timely manner. This procedure calls for the assigned department, upon completion of the required action, to submit the response to the Licensing Department. The Licensing Department then reviews the department response to ensure that all required items are address-ed, that all Commission rules and requirements, if any, have been met, and then prepares a final submittal based on the information provided. The procedure then calls for the final submittal to be distributed to key personnel, including the preparer's department, for review and approval. These reviews are documented and any comments on the final submittal are resolved by the Licensing De-partment. Upon resolution of the reviewers' comments, if any, the District's response is submitted to the Division Manager - Pro-duction Operations for his review and approval. Upon his signa-ture, the document is transmitted to the Commission.

The response to IE Bulletin 82-02 was handled in accordance with the above mentioned procedure. The Licensing Administrator assign-ed the required action to the Technical Services Section. The as-signment was given to a recently hired engineer within the Techni-cal Services Section who had considerable previous utility engi-neering oxperience. During the development of the response, the engineer interviewed plant maintenance personnel familiar with maintenance procedures relating to the threaded fasteners on the reactor coolant system boundary. Based on those interviews, the engineer prepared the response to the bulletin. The response was signed by the Section Manager - Technical Services and sent to the Licensing Department. A final submittal was then prapared based on the information provided. This document was then distributed

E

j. _

. Mr. J . T. Collins

LIC-84-209 Page Three 1

for review in accordance with the District's previously described l -review procedure. This' response was reviewed by the Division j Manager -' Production Operations, Division Manager - Quality As-

.surance & Regulatory Affairs, Section Manager - Operations, 3

Section Manager - Technical Services (designated-alternate), Manag-er - Operations Technical -Support Services, Manager - Admini-i strative Services, Manager - Fort Calhoun Station (designated alternate), and' Licensing Administrator. Reviewers' comments were resolved and, consequently, the District' submitted the response 4 signed under affidavit, as required'by the bulletin.

The previously described review procedure has' proven in the past j to be an effective and reliable method of assuring the accuracy j and completeness of the District's responses to the Commission..

As with any procedure or practice, there are isolated cases where

}

i breakdowns may occur and the desired results are not always

{ achieved. The District. firmly. believes that this is the situation

! which existed in this-case. The District. believes that the pro- ,

j cedures and practices for the receipt of correspondence from the '

] Commission, preparation of responses, and the review of those re-

! sponses in place at the time the response to IE Bulletin 82-02 was  ;

j prepared are indeed thorough and effective. However, plans have j been made to review these procedures and practices with the in-j tention of' implementing improvements which will assist in assuring

that opportunities to introduce _ errors are reduced or eliminated.

! This review will be . completed by July 31, 1984 and any revisions

} or_ changes in procedures or practices will be implemented as soon 1 as practical thereafter.

) Since the time when the response to IE Bulletin 82-02 was pre-j' pared,'the District'has implemented or is implementing the-fol-j lowing three' programs which have the potential for assisting per-j sonnel .in the accumulation of information for development of re- ,

i sponses to the Commission. The first program is the computerized.

records management system which has been implemented and is functional at the present time. .The second program is the com- 6 a puterized history _.and maintenance planning system'which is'present-i

.ly in the process of-being implemented. :The .hird program relates 1 - to controlling of - vendor . information. - The details of this program

, are addressed in 'the NUTAC report on vendor 'information (Generic l Letter 83-28, Section 2.2.2). This NUTAC report describes an t- alternative program to address: Generic Letter 83-28,'Section j 2.2.2. In general, the uUTAC program. consists'of'the following f three major areas: active participation in the Nuclear-Plant Reli-ability Data System (NPRDS),Lactive participation in the Signifi-I cant Event Evaluation and InformationLNetwork (SEE-IN), and in-4 Eternal handlingiprocedures for ' equipment technical information. i 4

The District is presently reviewing the NUTAC report in an attempt-to determine exactly. -the extent that can be ' implemented. When

_---._-._-.-..__._---.----__.-___.-.____=v,--c.x

Mr. J . T. Collins

' LIC-84-209 Page Four implemented, the above mentioned improvements can be utilized in

-the development of District responses relating to equipment history, equipment maintenance, equipmeat operation, and vendor information.

Attachment 1 is submitted to reinforce and document the District's compliance with Regulatory Guide 1.65 (October, 1973) relating to reactor vessel studs. This attachment gives a point-by-point re-view of Regulatory Guide 1.65 and how the District addresses each point. An analysis was previously performed in February, 1983 in order to exclude the reactor vessel head closure studs from re-quirements of IE Bulletin 82-02. The District believes this at-tachment adequately demonstrates compliance with Regulatory Guide 1.65 (October, 1973).

The District is presently investigating, for the time period be-ginning with the start of commercial operation of the Fort Calhoun Station up to the present time, the types of lubricants which have been used on bolted closures of the RCPB components. These com-ponents were identified in the District's response (LIC-82-269) dated August 2, 1982 to Item 5 of IE Bullet!.n 82-02. The above mentioned investigation, based on information contained in mainte-nance records, will be completed by August 15, 1984.

Sinc ely, R. L. Andrews Division Manager Nuclear Production RLA/JJF:jmm cc: LeBoeuf, Lamb, Leiby & MacRae 1333 New Hampshire Atenue, N.W.

Washington, D.C. 20036 Mr. E. G. Tourigny, Project Manager Mr. L. A. Yandell, Ser.ior Resident Inspector

~ . - . - . .. - - - - - . - -- -- .- -. - - --.

.I

- Attachment 1 Compliance with Regulatory Guide 1.65 (Oct.1973)

Relating to Reactor Vessel Studs 4 This attachment provides a point by point review of Regulatory Guide 1.65 (Oct.1973) and the examination and maintenance methods practiced by the District in demonstration of the District's commitment to this Regulatory Guide. ,

Reg. Guide Section C.1.a. States:

1. Bolting Materials i

i a. Reactor vessel closure stud bolting should be fabricated from i materials which have adequate toughness throughout the life cycle of the reactor. Stud bolting should meet the requirements set

! forth in Subsection NB, " Requirements for Class 1 Components,"

Section III of the ASME Code. Bolting materials should meet the requirements of one of the following ASME specifications:

(1) SA-540 Grade B-23 and B-24 bar (AISI 4340).

j j (2) SA-193 Grade B-7 bar (AISI 4140, 4142, 4145).

]

(3) SA-194 Grade 7 (nuts for bolting) (AISI 4140,4142,4145).

{

i (4) SA-320 Grade L-43 bar (AISI 4340).

! Response 1

j- The Combustion Engineering Reactor Pressure Vessel Manual and the mater-j 1al certification records indicate that the reactor vessel closure studs were fabricated of material meeting the requirments of ASME

! SA-540, Grade B-24. Nuts and washers were fabricated from requirements of ASME SA-540, Grade B-23.

Reg. Guide Section C.1.b.(1) States:

b. The requirements of the specificaticn in paragraph C.1.a should

be supplemented by the following

(1) The maximum meawrad ultimate tensile strength of the stud

. bolting material should not exceed 170 ksi.

Response

4 Material certifications for the reactor vessel closure studs indicate that the studs have an ultimate tensile strength of less than 170 ksi.

Reg. Guide Section C.1.b.(2) States:

f I

! (2) Charpy V impact testing should be perfomed according to '

ASME SA-370, " Methods and Definitions for Mechanical l Testing of Steel Products," and to be acceptable, the results must satisfy the requirements of-Paragraph IV.A.4.

-of Appendix G to 10 CFR Part 50.

1

__ _ _ . _ . _ _ . - _ _ _ . _ . ~ _ , , . _ _ _ _ _ . . _ _ _ _ . , _ _ .

o :

~

In case a test fails, one retast may be conducted according to subsubarticle NB-2350 of Section III, ASME Code.

Response

J, Regulatory Guide 1.65 was issued in October,1973, whereas the Fort Cal-houn Station reactor vessel was designed and fabricated to the require-ments of the 1965 edition of A91E Section III, including the 1967 Winter Andenda &ccording to the Fort Calhoun Station USAR. Appendix G was not added to 10 CFR Part 50 until 38 FR 19014, July 17,1973; this too post-dates the construction of the Fort Calhoun Station. Charpy V impact testing was perfomed in accordance with the appropriate Codes

in effect at the time of fabrication of the bolting.

1 Reg. Guide C.1.b.(3) States:

i Stud bolting should not be metal-plated unless it has been (3)

. demonstrated that the plating will not degrade the quality

} of the material in any significant way (e.g., corrosion, H2 j enbrittlement) or reduce the quality of results attainable by the various required inspection procedures. The stud j bolting may have a manganese phosphate (or other accer+-

able) surface treatment. Lubricants for the stud bolting are pennissible provided they are stable at operating temperatures and are compatible with the bolting and vessel materials and the surrounding environment.

Response

l 4

No metal plating was specified for the reactor vessel studs according i to CE drawing E 232-420, Stud, Nut, and Washer Details. This drawing i indicates that, following manufacture, the studs, nuts, and washers i were to be " coated with an antigalling coating in accordance with C.E.

j M&P Spec. 4.4.4.1(a)." This drawing also states that "At installation, lubricate threads of studs, plugs, and bearing surfaces of nuts and washers with Super-Moly," which contains MoS2 . The CE Reactor Vessel i manual . specifies the use of Super Moly lubricant for vessel head bolting.

i The use of Super-Moly is also found by CC to be " acceptable for use on j items which will not come in contact with primary coolant," per l CEND-353, Rev. 6, Aug.1977, Field Handling, Maintenance, and Storage i , Requirements for Combustion Engineering Furnished Equipment. That

! document was prepared by the Nuclear _ Power Setvices department of Combustion Engineering, Inc. Recent conversations with CE concerning the appropriate lubricants to use in another RCfB closure indicated i that CE continues to recommend the use af a lubricant which contains i MoS2 -

i 1 Reg. Guide 1.65 cautions against the use of metal-plating on bolts which can lead to cracking or severe galling. It is interesting to

note the Reg. Guide goes on to mention that " replacement stud bolts in i

Yankee Rowe which had a manganese phosphate surface treatment in combination with MoS2 as a lubricant demonstrated superior resistance to galling when compared to the original ' silver-plated stud bolts."

2

a :

Reg. Guide S;ctions C.2.a. and C.2.b. Statn

. 2. Inspection The nondestructive examination of the stud bolts and nuts should be performed according to subsubarticle NB-2580 of Section III of the ASME code as supplemented by the following:

a. The stud bolts and nuts should be ultrasonically examined after final heat treatment and prior to threading.

b. The ultrasonic examination (paragraph NB-2584) should be conducted according to ASME Specification SA-388, " Ultra-sonic Examination of Heavy Steel Forgings."

4

. Response The material certification records indicate that the bars and tubes from which the bolting was fabricated were examined for defects using ultrasonic examination methods. In addition, the drawing CE 232-420

. indicates that "Before and after threading, studs (PC No. 420-01) are to be magnaglow inspected in accordance with paragraphs N-626.3(b),

, Section III, ASME Code. Acceptance to be in accordance with Pai agraph N-325,Section III, ASME Code." Again, the reactor vessel was designed and fabricated to the requirements of the 1965 edition of ASME Section III including the 1967 Winter Addenda. Thus, the studs were adequately

examined for defects at the time of manufacture. In addition, all 48 reactor vessel closure studs have received Inservice Examination

, including magnetic particle and ultrasonic examination as required by 2

and in accordance with the 1971 edition of ANE Section XI including the 1972 Summer Addenda and the 1974 edition including the 1975 Summer Addenda and the corresponding requirements of ASME Section Y. The 3

ultrasonic examinations have been perfonned from the center drilled

hole extendirig the length of the studs. The requirenents of the j in-service inspection program supercede the inspection performed at the i time of fabrication.

Reg. Guide Section C.2.c. States:

i 2

c. The calibration standard used to establish the first back

reflection for the ultrasonic testing should be based on good sound representative material . To assure that the material is representati%, we selection of the standard should be based on a preliminary ultrasonic examination of a number of specimens (a minimum of three per standard).

Response

The calibration standards used for ultrasonic examination during inser-vice exams complied with the ASME Section XI and Section V Codes in i

effect at the time of the individual examinations. The requirements of 4

the in-service inspection program supercede the inspections performed at the time of fabrication.

Reg. Guide Section C.2.d. States:

d. The magnetic particle or liquid penetrant examination i (paragraph NB-2583) should be perfonned on the studs and nuts after final heat treatment and threading.

3

Response

The drawing, CE 232-420, indicates that "All Fabrication Shall be in Accordance with ASME Boiler Code Section III." Again, the reactor vessel was designed and fabricated to the requirements of the 1965 edition of ASME Section III including the 1967 Winter Addenda. As stated previously, the drawing also indicates that the studs were to have been "magneglow inspected in accordance with paragraph N-626.3(b),

Section III, ASME Code." This was to have been done both before e.nd after threading. Also, all studs and nuts have been subsequently exam-ined with the magnetic particle method through the inservice inspection program.

Reg. Guide Section C.2.e. States:

e. The requirements of paragraph NB-2585 should be applied to all closure stud bolts and nuts.

Response

The Winter 1967 addenda of A94E Section III is indicated by the USAR to have been used to specify the design and fabrication requirements for the reactor vessel .

Reg. Guide Section C.3 States:

3. Protection Against Corrosion During venting and filling of the pressure vessel and while the head is removed, the stud bolts and stud bolt holes in the vessel flange should be adequately protected from corrosion and contam-ination.

Response

The Fort Calhoun maintenance and operating procedures contain measures to protect the stud bolts and vessel flange bolt holes from corrosion and contamination. The stud bolting remains with the vessel head when it is lifted (prior to reactor cavity flooding) to its storage location. This storage location is out of the reactor cavity and in a reasonably clean, dry and low traffic area. The vessel flange bolt holes are either filled with a corrosion inhibitor and plugged prior to flooding the reactor cavity or alignment pins are installed.

Reg. Guide Section C.4.a. States:

4. Inservice Inspection The inservice examination of the pressure vessel stud bolting should be performed in accordance with the requirements of Section XI of the ASME Code as supplemented by the following:

a. The inservice inspection should include a surface examin-ation which should be in accordance with paragraph NB-2545 or NB-2546 of Section III of the ASME Code. For this inspection the studs should be removed from the pressure ves sel .

4

3 s

y Response In 1975, one third (16) of the sets of vessel bolting were examined using visual, magnetic particle, and ultrasonic methods in accordance c

with the 1971 edition of the ASME Section XI Code including the 1972 Summer Addenda. The magnetic particle examination results were evaluated in accordance with "the applicable portions of Section III of

the ASME Code and any indications which exceed those criteria shall be reported to the customer for evaluation and/or disposition." No indications exceeding those criteria were found. In 1980, another 16 sets of vessel bolting were examined. Again, the examination procedure required notification of the customer for evaluation and/or disposition if an indication were found which exceeded criteria identical to the

criteria found in paragraphs NB-2545 of Section III of the ASME Code.

Indications which exceeded the Section III criteria (but not the Section XI criteria) were reported to 0 PPD by the ISI examiner. The indications were described as " tool marks," not cracks or corrosion and were found to be located at the very top of the stud in a non-stressed area or on outside surfaces of the nuts and detennined by 0 PPD to be acceptable without repair. In 1981, the remaining 16 sets of vessel bolting were examined using the ultrasonic and magnetic particle

methods completing 100% of the reactor vessel bolting exams. The I examination procedure required notification of the customer for any indication which exceeded criteria identical to those found in Para-

! graph NB-2545 of the ASME Section III Code. Indications were described

as " tool marks" and were found in non-stressed areas of the studs or on outside surfaces of the nuts. These were again detennined to be i acceptable without repair. All of the studs were removed from the vessel in order to accomplish the surface examinations.

Reg. Guide Section C.4.b. States:

b. Selection of the bolting material for each required inser-

, vice inspection should be based on a representative sample i and on a reasonable geometric distribution.

Response

During the first 10 years of service,1/3 of the bolting was selected for each of the three series of inservice examinations. The selection

was in a unifonn fashion from the entire circumference of the vessel l

flange.

1 The District renains conmitted to the Inservice Inspection criteria of

! Reg. Guide 1.65. These criteria for' representative sampling and for the requirements of paragraph NB-2545 for surface examination are being 7 included in the current development of the inservice inspection program for the current 10 year' inspection interval, 1983-1993.

l The District believes that this point by point review of Reg. Guide 1.65 and the examination and maintenance methods practiced by the Dis-l- trict shows "ccomitment" to the Reg. Guide as required by IE Bulletin.

82-02 in order to exclude the reactor vessel head closure studs from

the requirements of_ IE Bulletin 82-02.

5'

. _ _ _ . _ _ _ _ _ _ . . . . _ . - , _ . _ _ _ _ _ . ,. _ . _ _ _ _ ._