ML17199T445

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Forwards 870409 Status Rept Describing Progress in Resolving Questions About Installed Configuration of Embedment Plates, Per
ML17199T445
Person / Time
Site: Dresden, Quad Cities, 05000000
Issue date: 04/10/1987
From: Johnson I
COMMONWEALTH EDISON CO.
To: Davis A
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
2855K, NUDOCS 8712010013
Download: ML17199T445 (15)
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Text

Common&lthEdlson.

One First National Plaza, Chicago, Illinois Address ReplY to: Post Office Box 767.

Chicago, Illinois 60690 - 0767 Mr~ A. Bert Davis Acting Regional Administrator U.S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, IL. 60137

  • April 10, 1987 subject:

Dresden Station Units 2 & 3 Quad Cities Station Units 1 & 2 "Embedment Plate Status Report" NRC Docket Nos. 50-237, 249, 254 & 265

Dear Mr. Davis:

t 7hrl

\\,. =la~~~~l-..J As agreed in Mr. c. Reed's letter to you dated March 6, 1987, attached is a status report dated April 9, 1987 describing our progress in resolving questions about the installed configuration of embedment plates at Dresden Units 2 and 3 and Quad Cities Units 1 and 2.

/klj att.

cc:

M. Grotenhuis-NRR R. Bevan-NRR M. Ring-RIII I. M. Johnson Nuclear Licensing Administrator 2855K 8712010013 e~g37 PDR ADOCK 0. PDR R

..... * ~***

Weekly Status Report Assessment of Embedment Plates Status as of April 9, 1987 Commonwealth Edison Company Dresden Station - Units 2 and 3 Quad Cities Stations - Units.l and 2 April 9, 1987

I.

Introduction This is the fifth of a series: of weekly reports which address the effort to. resolve the issue regarding *the embedment plates which Were constructed*..

with strap anchor spacing other than those used in the design.

The pufp6se of this report is to update the Nuclear Regulatory Commission, Region III regarding the status for this effort. This fifth weekly report consists of a summary of work performed duri.ng last week.

II. Dresden Station*

Per the Milestone Bar Chart (Attachment I) phase i, a walkdown effort at Dresden is continuing.

The current cumulative status is indicated in Attachment 4A.

A number of the ultrasonic test results have been received for evaluation.

These results ind1cate that strap anchor ~pacings of 18 11

  • (+ lu) o.c. and 24 11 (:!. 1 11

) o.c. are present at Dresden.

In light of this new information*

(24 11 spacing) two tasks have been determined and are underway.

1.

New generic embedment plate allowable loads using the 24° on center strap anchor spacing and smallest attachment size h*ve been developed.

The at;ceptance criteria for developing these a 11 owab le loads is the same as that used for the 18 11 on center strap anchor spacing.

The 24" spacing QBE and SSE allowable loads have been found to be the same as those for the 18 11 spacing situation.

The upper limit allowable load for 24" spacing is slightly less than that for 18 11 spacing.

These results indicate that the 24 11

~p~cing will have a minimal impact on the overall assessment program as explained below.

.The initial sorting of hangers to determi~e the wal.kdown scope.considered.

all three.allowable loadvaluesfor.18 11.spacing: The hangers not*

meeting generic upper limit allowable loads (Load >,Upper. Lim.it) were considered a part of the wa 1 kdown scope.

The hangers which met ge_neri c upper limit allowable loads but did not meet the QBE and/orSSE allowable loadi (Load> FSAR Limit) were also considered a part of the walkdown scope.. Thus, the total walkdown scope included all hangers which did not meet the FSAR allowable loads.

Since the F~AR (i.e., QBE.

  • a~d SSE) allowable loads for 24" spacing are the same as those for 18 11 spacing, the total walkdown scope does not change.

Hence, the impact of 24 11

  • spacing can be summarized as follows:

a) A total number of hangers requiring a field walkdown remains the same.

b)

The number of hangers requiring a walkdown because they exceed upper limit loads will increase while the number of hangers requiring a walkdown because they are less than upper limit loads but greater than FSAR loads will decrease.

c) Allowable loads for larger attachment sizes have,~o be d~veloped for the 24 11 spacing.

If a comparison of these

. reveals that FSAR allowables loads for 24 11 spacing for the larger attachment sizes are less than those for the 18 11 spacing, some earlier sorting calculations may have to be review~d. If such a review r~veals that hangers do not meet the new generic allowable loads, additional ultrasonic testing may be required.

2.

The original shop drawings have recently been obtained from one.of the detailers.

Th~ plates wit~ 24 11 spacing were a part of this *detailers scope.

A review of the,se drawings indicate that S&L liad the latest drawing revision pertainirig to these plates and the as-detailed spacing of strap anchor~ for these embedm~nt plates is 18 11 Thus, it is believed that the 24 11 spacing resulted from either a detailer-fabrication interface not recorded on the detail drawing or a misinterpretation of the detail drawing.

An understanding of what occurred would help determine which p-lates one likely to have the 24 11 spacing.

Effort is presently underway to develop this understanding.

The numbers presented in the attachments have not been revised to incorporate the effect of 24 11 spacing for two reasons:

a.

Based on wb~t has been done so far, the 24 11 spacing is not expected to have any significant impatt on th~ assessment program..

b.

It is anticipated that the two tasks described above, will be completed shortly. A shows the present status of ultrasonic testing data.

and resulting embedment plate assessment.. The assessment in this phase is based on ~he walkdown results for both the hanger attachment and strap anchor location.

~-..

III.. Quad C{fies Station The phase i walkdown effort at Quad Citie.s began on March 30,. 1987.

Per the Mileston~ B~r Chart (Attachment 1), the walkdown is continutng.

The current cumulative status is indicated in Attachment 48.

IV.

Attachments The following attachments are included in this weekly report.

l; Milestone Bar Chart - Dresden and Quad Cities

2.

Summary of Status - 2ADresden 28 Quad Cities

3.

Number of Embedment Plates - 3A Dresden 38 Quad Cities*

4.

Phase i - Walkdown and Evaluation Status Summary 4A Dresden 48 Quad Cities S.

Phase Phase ii - Walkdown and Evaluation Status Summary SA Dresden Note:

Attachments 1, 2 and 3 have not changed. A.and 48 have been revised to show current cumulative status. Attachment SA has be.en added.

ACTIVITY CE Co requests S6.L's aasistance for one fal led cmb. plate *t Dresden Unit 2 (2/11/87).

S6L asseSsea failed plate and i.nforms CECo that the strap spacing on emb. plate shop dwg. is different from S6L 1 1 design dwg.

CE Co request1 a review of ad-dltional shop dwga.,

a mockup plate ECN for UT calibration and determination of plate capacity per shop dwg. detal L Rep.1 i r of hi led plate la issued.

S6.L oi>tains print a of large bore hanger dwgs. with attach*

ment to emb. plate.

S6.L prepares hanger location dwgs.

SU sorts and plots hanger attachment a (draft ingl.

In addition, Sl>L locatu ae*m* of emb. plate* using piece marks on 1hop *dwgs, SU generates emb. plate capacity.

SU pe*r for ma an engineering assessment and identifies those hangers which meet th* shop dwg..

plate capac lty and hence are 0 f.

no concern.

Sl>L per form*

  • sort of remaining hanger* Into thooe which may potentially affect piping syatem*

function Ind those for which the embedment pbte F'SAR a J lowab lea ue exceeded.

2/9/87 2/16/87 2/2)/87 I

I r-------

~

I Dresden 26.J Bar Chart for Embedment Plate Issue Resolution Quad Cities 16.2 Bar Chart for Embedment Plate Issue Resolution W E E K B E c I N N *1 N C "

0 N D A Y

)/2/87

)/9/87

)/16/87

)/2)/87

)/)0/87 4/6/87 I

r---'

-~

I I

I ------_J Pag.e 1 of.2 r-..:...------.

L.------~

DRESDllhl

. QLJl\\D *c1TI*$

4/1)/87 4/20/87

.. 4/27 /87 I

I I

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ACTIVITY S&Lt\\.t\\.o per forms

  • wa **aovn for those hangers which may f'otcnt ial ly afrect piping sy!i'Otcm analysii; and determine

..ll tachmcnt location relative tu ed~cs ol cmL. pl*** and

~trap.

If n~cessary, CE Co performs UT for strap location.

Sli.l ut t l izes walkdown dat* to perform a sorr ol these h1nl',ers to idC'nt i fy tl1ose h~ngers which st i 11 may potentially affect pipinr, ~vste~ analysis.

-. Sl>L/CECo perform a wa lkdovn for thO!!'l' hangers which may potentially cause eml>edr.tent plate FSAR al low-ables to be exceeded.

AS!iOCSS these h.lngers baaed on walkdown data and issue repair a as necessary.

.'9/87 2/16/87 2/2)/87 I

(

' i I

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/

I (Continued)"

Dresden 26J B*r Chart fo.r Embedment Place Issue Resolution

~uad Cities 1&2 Bar Chart for Embedment Plate Issue **solution W E E K 8 E C I N N I N C H 0 N D A Y

)/2/87

)/9/87

)/16/87

)/2)/87

)/)0/87 4/6/87 o--

CONTl.,UING Page2 of L.

4/l)/87 4/20/81 COIJTIWUllJG I

i. /'1118 7 I

J\\ t toclvncn t 21\\

Status Swnmory Dre~:dcn APPROXIMATE NUMBER OF LARGE BORE PIPE HJ\\NGERS ON EMAE'ENT Pl.ATES Total In Unit In Unit S~fety

. Nonnafcty Reactor Turhine Load G ;>

r.6.ads >

Description

  1. 2
  1. 3 Related Related.
Bldg, Bldg.

Upper F'SAR Limit*

Large bore hangers collected for follow-up work 2230 1660 1170 750 1.480 1460 770 Result of first sort using generic 2!" x 2t" 440 230

?.JO 170 270 380 60 250 190 attaclvnent size allowable limits (number of hangers requiring follow-up work)

Results of second *sort using generic larger 355 202 l 53 111 244 288 67

. 181

  • 171,**

etteclunent size allowable limits where applicable (number of hangers requiring follow-up work)

Result of welkdown end evaluation for hangers with loads ->allowable upper limits (number of

  • hangers requiring follow-.up work)

- Phase i - Visual date obtained from floor

- Phase ii - Utilizing UT date for strep location Result of walkdown end eveluet.ion for hangers with load ) allowable FSAR limits (number of hangers requiring follow-up work)

- Phase i - Visual date obtained from floor_:..

- Phase

~

ii - Utilizing UT date.for strep location The table above describes the results of large bore hanger drawing collection, plotting and sorting, Numerical values 'represent number of hangers and are approximate numbP.rs..

  • 76 Sefe.ty-related, 105 Nonsafety-releted
    • 35 Safety-related, 139 Nonsafety-releted

.. B Status Summary.

Quad Cities APPROXIMATE NUMBER OF 1.ARr.Jl RORE PIPF. HANC:F.RS ON F.f"RF.O"!F.NT PLAT'!S

  • Total In Unit In Unit
  • Safety Nonaafety Reactor Turbine Loads>

Loads>.

DESCRIPTION*

  1. 1
  1. 2

.Related Related Bldg.

Bldg.

Upper

  • FSAR L.imit Large bore hangers collected for follow-up work (Excludes 60 hangers on different strap plate) 2000 1000 1000 400 1600 1380 620 Result of fl rat sort using generic 2!s" x 2!s" attachment size allowable limits (number of hangers requiring fo4low-up work)

Results of second ao~t using generic larger attachment size allowable limits.where applicable 220 126 94 74 146 110 llO 105

  • 115 **

(number of hangers requiring fo llow*up work)

Result of walkdown and evaluation for hangers with loads > allowable upper limits (numbef. of hangers requiring foilow*up work)

  • Phase i
  • Visual data obtained from floor
  • Phase ii - Utillzl~g UT data for strap location.

Reau 1 t of walkdown and evaluation for hangers with load > allowable FSAR limits (number of hangers

  • requiring follow-up.. ark)

.e

- Phase i

  • Visual d£ta obtained from floor

- Phase ii - Utilizing UT data for atrap locat l,.lla

/

The table above describes th9 results of* large bore hanger drawin~ collection 1 plotting and sor~ing.*. Numerical values represent number of hangers and are'arproxi~te numbers.

  • 29 Safety-related, 76 Nonaafety*related
    • 45 Safety-related, 70 Nonaafety~related

Attachment #3A N~mber.of-Embedded Pl~be~

Dresden

  • The following table shows a breakdown of number of embedded plates with large bore pipe hangers attached to them. The numbers ~ndicated-are approximate.

Bldg -

Unit Unit #2 Unit #3 Total Reactor Building 360 470 830 Turbine Building 90 100 190 Total 450 570 1020

~..

Attachment :33 *

  • Number of Embedded Plates Quad Cities The following table shows a breakdown of number of embedded plates with large bore pipe hangers attached to them.

The numbers indicated are approximate.

Bldg - Unit Unit #1 Unit #2

  • Total Reac.tor Building 400 400 800 Turbine Building 180 190 370 Tot:al 580 590 1,170

flTTf,CHMENT 4B Phase i Wulkdown and Evaluation s'tatus SWmlary - Quad Citir>s Note:

Evoluete Ccmpare loads with upper limit and FSAR allowables for the specific. uttachment location to detennine.whether these limits are satbfled.

(\\ P PR 0 X IM ATE NUMBER 0 F U P P E R L I M I T H A NG E R S (UL)*

A p p R 0 x I M A T F.

N U M fl.E R 0 F' F'S fl R flANQERS CumulAtive Walked Evaluated S 0 R T 0 F EV A L.U ATE D H A N G F. R s*

Status as Do*n Satisfies Satisfies UT Requested flecause Deing Walked Evaluated Sort of Evaluated lfongcrn Heint; of Upper Limit FSAR (Subset Does Not Satisfy Evaluated Down Satisfies FSAR UT Requested 11ecuusc Evaluated of 3)

UL FSAR Doc::; No't Snt 1,,;fy FSAR 0

0 0

© Q){D-G: ©00 @=0©

© G)

@=-

0-0 (Subset of 4/2/87 20 0

0 o*

0 0

20, 16 0

0

  • o

.16 4/9/87 33 18 J

3 15

  • 15 15 20 11 9

2 9

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11.TTl\\CllMl~NT Ml Pha"e 1 Wnlkdown ond Evaluation Stntus Summary -

Dre<Jden Note:

Evaluate Compare loads* with upper Umit end F.SAR allowables for the speclf'ic attacrmenL location to detennine whether these lJmHs are sutifiHed.

11.* P P R 0 X I M I\\ T E NUMBER 0 F u p p E R L I M I T H A N 1; E fl s (!JI.)

-1.

.!.'_! !' ~ 0 x IM A T E N U M fl E H 0 v F S /\\ Jl II fl N t: 1,: I!:.;

Cumu] atl ve

  • Walked Evaluated S 0 R T 0 F EV AL IJ ATE D H ii ii*c*~: R *S,.

Stat.u~ es Down Satisfies Satisfies lIT lleciuested Because neing Walked F.va]uated

.Sort. or F.w1]11atcd lloni;er:*:

Belr~i of Upper Limit FSAR (Subset Does Not Sat h:fy

  • Eveluat.ed Down Satisf'ies

~;l\\Jl UT JlP.quectect l'\\cr,Ftll!>e J'valua J.ed Q)

Q) of~

UL r.i/\\Ji D'NoL Sul.~ ~C.l\\ll @=-

<l;@-Q) ©0-©

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1ll.

( u~t of I

J/18/87 43 18 12 7

6 IJ

>5 JO J

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n J/26/87 71 67 46 J8 21 29 64 I,

50 JJ 17 l /,

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4/2/87 107 99 61

50.

J8 49 8

87 81 57

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4/9(87 122 107 69 53 38 54 15 91 80 47 33 11 i

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  • ---****-*.. *-----. *- *-*-*---* L ----**-**

U.T.

Cummulative Requested Status As Of CD 4/9/87 38 Attachment SA Phase ii Walkdown and Evaluation Status Summary -

Dresden This table represents the status of those hangers for. which u. T. ¢la.ta was requested, Thesr-hangers fall into the categories shown below.

APPROXIMATE NUMBER OF UPPER LIMIT HANGERS (UL)

APPROXIMATE NUMB.ER OF FSAR HANGERS Sort of Evaluated Hangers U.T.

Being U.T.

U.T.

Sort of. Evaluated Hangers Befog Received Evaluated Evaluated Requested Received Evaluated Evaluated Upper Limit FSAR Limit UL Does Not

  • noes Not Does Not Satisfies Satisfies Satisfies Satisfy FSAR sausfy

. Satisfy FSAR UL FSAR "PSAR Q)

-G>- ©

D-G)-@ KID-@- G:>

@-@ ~@ §-*@-@

34 7

7 0

7 0

27 49 23 10 10 0

13 I

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