ML19209A502

Requests Advance Approval for Nondestructive Examination Exemptions Requested in Wf Naughton to HR Denton.Review of Plant Design & Capabilities Indicates Exemption Will Not Decrease Safety

ML19209A502
Person / Time
Site:	Zion File:ZionSolutions icon.png
Issue date:	10/01/1979
From:	Peoples D COMMONWEALTH EDISON CO.
To:	Harold Denton Office of Nuclear Reactor Regulation
References
NUDOCS 7910040259
Download: ML19209A502 (13)

Text

I Commonwealth Edison One First National Plata. Chicago lifinos Address Repfy to Post Office Box 767 Chicago. Ilhnois 60690 October 1, 1979 Dr. Harold R.

Denton, Director Office of Nuclear Reactor Regulation U.S.

Nuclear Regulatory Commission Washington, D.C.

20555

Subject:

Zion Station Unit 1 Request for Advance Approval for NDE Exemptions to Inservice Inspection (ISI) Program NRC Docket No. 50-295 Reference (a):

June 28, 1979 letter from W.

F.

Naughton to H.

R.

Denton containing revised ISI Program for Zion Station

Dear Dr. Denton:

Commonwealth Edison Company requests the Nuclear Regulatory Commission (NRC) Staff for advance approval for Zion Unit 1 of the non-destructive examination (NDE) exemptions requested in Reference (a), which contains the revised Inservice Inspection (ISI) Program for Zion Station.

Approval is needed by October 15, 1979.

The basis for this request follows.

In Reference (a), Commonwealth Edison requested relief frcm certain NDE requirements of ASME Section XI, 1974 Edition, Summer 1975 Addendum.

Specifically, the items identified in Reference (a) were Paragraphs II and N of the program text and Notes 12, 19, 20, 21 and 22 to the Class 1 Component Examination Table.

For your convenience, these items have been extracted from Reference (a) and are included as Attachment 1 to this letter.

Currently, for Zion Unit 1 the completion date for the second 40-month period of the 10-year interval is August 31, 1980.

Thus, without relief these examinations would have to be performed during the forthcoming refuelina outage which commences on October 6,

1979.

Of particular concern are the examinations relating to Note 19.

Items Bl.13 and Bl.14 of ASME Section XI, 1974 Editior, requires the examination of reactor vessel and reactor vessel head cladding.

These examinations would result in personnel exposures in excess of 1.5 person-rem for craft support to prepare the vessel head cla patches and 1.5 person-rem for the Level II NDE examiner.

7910040 2_S7 1090 0/6

Commonwealth Edison NRC Docket No. 50-295 cr. Harold R. Denton: October 1, 1979 As described in Paragraph H of the Program (see Attact. ment 1), the cladding is not required to support the stress loads of the vessel.

The stresses are adequately accommodated by the ferritic base material which is exa'ined volumetrically as required by other examination categorit3.

In addition, the requirements for these examinations have beei deleted from the 1977 Edition of ASME Section XI.

In conclusion, a review of plant design and the capabilities of Non-Destructive Examination (NDE) techniques indicates that granting these exemption requests will not result in a decrease in the safety of the plant.

Please address any questions that you might have concerning this matter to this office.

One (1) signed original and thirty-nine (39) copies of this letter are provided for your use.

Very truly yours, i

-f L

, Lcy J /

D.

Louis Peoples Director of Nuclear Licensing attachment 1090 D//

E3GPf_t_ipns_ t,o_ ASME Sec,t,iop, XI, F_elatino t,o, A,dyan,ce_d, Apprpyal_ Pecues,t,,

The following pages are excerpted from the Zion Station I.S.I. Progran Desubmittal of. Tune 28, 1970 The items of interest as described in the attached letter are identified with an asterisk (*).

1090 0/8

i

1. (11)

Relicf is taken from stamping or otherwise physically mark-

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ing welds for identification and location as required by A'ppendix I, I-6200.

This marking was not performed at the time of the preservice inspection.

As an alternative, a means of establishing a uniform datum point for each wcld is maintained by procedurally describing datum or reference points such that subsequent relocation of the examination area can be achieved with an accuracy of 0.5 inches.

Ex-perience has shown the above alternative to be adequate in describing inspections and results.

The need for such marking, the resulting radiation exposure of personnel and the potential for introducing unduc stresses in the compo-3 nonts are not considered necessary in lieu of the alternative.

h (I)

Tables are attached to provide a listing of the ASME Code Class 1, 2 and 3 pumps and valves subject to the testing requirements of Subsections IWP and ITN of the ASME Hoiler

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and Pressure Vessel Code, 1974 Edition, and Addenda through Summer, 1975.

(J)

The tabulation of pumps identifies the pumps to be tested, pump code classes, parameters to be measured and test I

intervals.

The requirements for pump performance as currently specified in the plant technical specification is that de-l voloped head and flow be within + 10 percent of a point on the head curve.

Relief is requested from pump performance parameters of head and flow from having to meet the allowable O

r=#aa" or ecce ne "titice as acti"ca 1" renic 'ur-32oo-2 i

with the nubstitution of the to)crancen as currently defined in the plant technical specifications as allowed by IWP-3230.

l Page 0 of 83 10V() ()/ c)

i and 8.10, relief will be requested from the specific a

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.Section XI code requirementn and alternative examinat on or test requirements be proposed.

W (N)

Relief is taken from identifying Class 2 pressure retaining bolting exceeding 1 inch in diameter as examina-tion category C-D.

As an alternative, Class 2 pressure retaining bolting exceeding 2 inches in diameter will be It is felt that classified as examination category C-D.

the examinations required for Class 2 bolting need not exceed that of Class 1 bolting.

Additionally, guidance is provided by the 1977 Edition including Addenda through the Summer 1978 where examination category C-D applies to bolting exceeding 2 inches.

It is felt that no effect on O

plant safety will result.

Codes referenced as being applicable to construction of (0) components in the attached tables are:

III A ASME Boiler and Pressure Vessel Code,Section III, Class A Nuclear Vessels III C ASME Doller and Pressure Vessel Code,Section III, Class C Nuclear Vessels VIII ASMC Boiler and Pressure Vessel Code,Section VIII, Pressurc Vessels USA Standard USAS B 31.1 Code for Pressurc Piping 31.1 USA Standard USAS B 16.5 Steel Pipo Flanges, Planged 1G.5 Valves and Fittings 36.19 USA Standard USAS D 36.19 Stain 1 css Steel Pine e

.page 10 of 83 1090 080

Page 12 of 83 ZION UNIT 1 NUCLEAR PLANT INSERVICE INSPECTION FRCORAM ASME CODE CLASS 1 CCMFONE.NTS

• / v j

TABLE CODE TA3LE IWB-2500 APPLICABLE SEC' ION X1 Dl3-2600 EXA*-:INATION SYSTEM OR TO CC33 EXG'INATION RELIE?

I~E': ::0.

CATEGORY COMPONENT CONSTRUCTION AREA TO BE EXaMTNED REQUIRE:GNT RECIJESTED

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B1.4 B-D Inlet Nozzle to Shell Welds (4)

Volumetric No 31.5 B-E CROM, Vent and In-Core Instru-Visual No mentation penetrations and CRDM seal welds 31.6 B-F Primary Nozzle to Safe-End Welds Volumetric No

& Surface B1.7 B-G-1 Closure Studs (In Place),

Not Appli-No-Note 3 cable 31.6 3-G-1 Closure Studs and Nuts Volumetric Yes-Note 20 and Surface and 21 B1 9 B-G-1 Vessel Flange Ligaments Volumetric No B1.10 B-G-1 Closure Washers

Visual, No B1.11 3-G-2 Conoscal Bolting Visual Yes-Note 22 B1.12 B-If Integrally Welded Supports Not Appli-No-Note 4 cable B1.13 B-J-1 A

Closure Head Cladding Visual and Yes-Note 19' Surface 31.14 B-J-1 o

Vessel Cladding Visual Yes-Note 19 B1.15 B-N-1 o

Vessel Interior Surfaces and Visual Ko Internals O

B1.16 B-N-2 00 Interior Attachments and Core Not Appli-No-Note 5 Support Structures cable I

i 0

ZION UNIT 1.CCLEAR PLANT

/l l

INSERVICE INSPECTION PF.C3342?

ASME CODE CLASS 1 COMPONENTS TA3LE CODE SECTION XI TABLE L;3-2500 APPLICABLE CODE I'.i3-2600 EZ.O*INATION SYSTEM OR TO EXIEINATICN PELIEF ITEM NO.

CATEGORY COMPONELO CONSTRUCTION APEA TO BE EXAMINED REQUIREMENT REQUESTED

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3*.17 B-N-3 Core Support Structures Visual No 31.13 3-0 Control Rod Drive Housi6gs.

Volumetric No 31.1 9 B'-P Exempted Components Visual No B2.1 B-B Pressurizer III A Circumferential Shell Welds (5)

Volumetric No 32.1 B-B Longitudinal Shell Welds (4)

Volumetric No 32.2 B-D Nozzle to Vessel Welds (6)

Not Appli-No -Note cable 6

32.3 3-E Heater Penetrations Visual No 32.4 3-F Nozzle to Safe-End Welds (6)

Surface and No Volumetric 32.5 B-G-1 Pressure Retaining Bolting Not Appli-No-Note 8 (In Place) cable 92.6 B-G-1 Pressure Retaining Bolting Not Appli-No-Note 8 cable B2.7 B-G-1 Pressure Retaining Bolting Not Appli-No-Note 8 cable 32.8 B-E Integrally Welded Support Volumetric Ko 32.9 B-I-2 9'

Vessel Cladding visual yes-Note C

/9 52.10 B-P Exempted Components Visual

!To i

Manway Bolting Visual No B2.11 3-G-2 N

I

Page 14 of 83 ZION UNIT 1 NUCLEAR PLANT INSERVICE INSPECTION PROGRAM ASME CODE CLASS 3 COMPONENTS TABLE CODE TABLE IUB-2500 APPLICABLE SECTION X IWB-2600 EXAMINATION SYSTEM OR TO CODE EXAMINATION RELIEF ITEM NO.

CATEGORY COMPONENT CONSTRUCTION AREA TO BE EXAMINED REOUIREMENT REOUESTEC B3.1 B-B Steam Genera-III A Channel Head to Tubesheet Volumetric No tors (4) (Pri-Weld (4) mary Side)

B3.2 B-D Nozzle to Vessel Welds Volumetric No-Note 9 B3.3 B-F*

Nozzle to Safe End Welds (8)

Volumetric No

& Surface B3.4 B-G-1 Pressure Retaining Bolting Not Appli-No-Note S (In place) cable B3.5 B-G-1 Pressure Retaining Bolting Not Appli-No-Note 8 B3.6 B-G-1 cable Pressure Retaining Bolting Not Appli-No-Note 8 cable B3.7 B-H Integrally Welded Supports,

Not Appli-No-Note 8 cable B3.8 B-I-2 e

Vessel Cladding Visual Yes-Note 39 B3.9 B-P Exempted Components Visual No" B3.10 B-G-2 Manway Bolting Visual No B4.1 B-F Piping Pres-B 31.1 Safe End to Pipe Welds Volumetric Yes-Notel0 sure Boundary

& Surface B4.2 B-G-l*

C Pressure Retaining Bolting Not Appli-No-Note 8 (In place) cable B 4.' 3 B-G-1 CC)

Pressure Retaining Bolting Not Appli-No-Note 3

)

cable m

(r.

Page 15 of 83 ZION UNIT 1 NUCLEAR PLANT I

INSERVICE INSPECTION PROGRAM ASME CODE CLASS 1 COMPONENTS g

i TABLE CODE SECTION X3 TABLE IUB-2500 APPLICABLE CODE

WB-2600 EXAMINATION SYSTEM OR TO EXAMINATION RELIEF TEM NO.

CATEGORY COMPONENT CONSTRUCTION AREA TO BE EXAMINED REOUIREMEh"r REODESTED i

B4.4 B-G-1 Pressure Retaining Bolting not Appli-No-Note 3 cable B 4.,5 B-J Circumferential and Longitudi-Volumetric Yes-Notes nal Pipe Welds 10,11,16 17 B4.6 B-J Branch Pipe. Connection Welds Volumetric Yes-Note 7 cxceeding 6-inch diameter B4.7 B-J Branch Pipe Connection Weids Surface No 6-inch diameter and smaller B4.8 B-J Socket Welds Surface No B4.9 B-K-1 At Integrally Welded Supports Volumetric Yes-Note 12 B4.10 B-K-2 Support Components Visual No B4.ll B-P Exempted Components Visual Uo B4.12 B-G-2 Pressure hetaining, Bolting Visual No B5.1 B-G-1 Reactor Cool-Pressure Retaining Bolting Volume tric Yes-Moto 13 ant Pump

, (In place)

B,.2 B-G-1 Pressure Retaining Bolting Volume tric Yes-Note lh

& Surface i

i B5.3 B-G-1 Ch!

Pressure Retaining Bolting Visual No 3U,

"~

B5.4 B-K-1

}

Integrally Welded Supports Not Appli-No-Note 9 c>

cable 0C B5.5 B-K-2 23.

Su port Components Visual No l

9

Page 16 of 83 ZION UNIT 1 NUCLEAR PLANT

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INSERVICE INSPECTION PROGRAM ASME CODE CLASS 1 COMPONENTS TABLE CODE SECTION X TABLE IWB-2500 APPLICABLE CODE i

IWB-2600 EXAMINATION SYSTEM OR TO EXAMINATION RELIEF ITEM NO.

CATEGORY COMPONENT CONSTRUCTION AREA TO BE EXAMINED REOUIREMENT REOUESTED t

B5.6 B-L-1 Pump Casing Welds Volumetric Yes-Note kf B5.7 B-L-2 Pulp Casings Visual

'o B5.'8

,B-P Exempted Components Visual Mo B5.9 B-G-2 Pressure Retaining Bolting Not Appli-No-Note 8 cable B6.1 B-G-1 Valve Pres-A Pressure Retaining Bolting Volumetric Yes-Note 20 sure Boundary (In place)

B6.2

'B-G-1 ge Pressure Retaining Bolting Volumetric Yes-Note 20

& Surface B6.3 B-G-1 Pressure Retaining Bolting Visual No B6.4 B-K-1 Integrally Welded Supports Not Appli-No-Note 8 1

cable B6.5 B-K-2 Support Components Visual bo B6.6 B-M-1 Valve Body Welds Mot Appli-No-Note 8 cable B6.7 B-M-2 Valve Bodies Visual No B6.8 B-P Exempted Components Visual No CD B6.9 B-G-2

.,;)

Pressure Retaining Bolting Visual No CC; i

Q oc l

t r.

O g

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i the pipe side of the weld, which is a cast elbow, is machined for a distance of approximately 3 inches from the edge of the

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weld.

Ultrasonic examination is limited to this distance from the edge of the weld.

Examinations can be performed on the sur-face of the weld, but are severely limited from the nozzle side by the rough, or cast surface.

Surface examinations will be performed on 100 percent of the weld and the base metal on the pipe side.

The typical configuration is shown in Figure B4.1.

11.

In instances where the location of pipe supports or hangers re-strict the access available for the examination of pipe welds as required by IWB-2600, examinations will be performed to uhe extent practical unless removal of the support is permissable without unduly stressing the system.

WP 12.

The piping system integrally welded supports are attached to the pipe by fillet welds.

The configurations of such welds is such that volumetric examinations will not provide meaningful results.

Surface examination will be performed on integrally welded attach-i ments as an alternative to the volumetric examination.

I 13.

The reactor coolant pump seal housing bolts are of the socket head type and the configuration is such that ultrasonic examina-tions as required by IWB-2600 cannot be performed when the bolting is in place.

Examinations will only be performed when the seal housing is disassembled for maintenance to the extent required by IWB-2600.

1090 086 Page 20 of 83

l 18, Two of the reactor coolant pumps have integrally welded supports.

The geometric configuration and nature of the materials.of the pump support welds are such that ultrasonic examination cannot be performed as required by IWB-2600.

Surface examinations will be performed as an alternative.

The other two pumps have nc welds in this category and therefore, the examination requirements are not applicable.

1. 19.

Relief is taken from performing visual and surface or volumetric examinations on closure head cladding and visual examinations on reactor pressurizer and steam generator vessel cladding.

The design of these vessels accounts for the stress loads to be ade-quately accomadated by the ferritic base material which is examined volumetrically as required by other examination categories.

Addi-tional technical guidance is provided by later editions of Section XI where cladding examinations are no longer required.

1. 20.

Relief is taken from performing volumetric examination of bolting and studs.

Due to the inherent geometry of threaded fasteners j

and signal interference from the threads, volumetric examinations do not provide meaningful results.

Surface examinations of the threaded areas will provide the results necessary to ensure the pressure retaining ability of the components.

M 21.

Relief is take from volumetric examination of nuts two inches and j

greater in accordance with IWB-2600, Item 31.8.

Ultrasonic tests l

will not provide the needed information on axial running defects l

which are the only defects that would reduce the components ability to perform its intended function.

As an alternative, surface examina-l tions will be performed.

These examinations will provide adequate i

margin,s of safety.

Page 22 of 83 070 08/'

t f 22.

Relief is taken from the visual inservice inspection of reactor vessel' head penetration -conoscal bolting.

These bolts are replaced each refueling outage with new parts.

The normal material receipt inspections performed in accordance with the' CECO Quality Assurance program will ensure the integrity c f these components.

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Page 23 of 83 10'/U 088 I