ML20092A426

Responds to Confirmatory Action Ltr RIII-91-016A Re Commitments on Circulating Water Sys Pipe Rupture on 911222.Event Description & Chronological Sequence of Events Discussed in Encl

ML20092A426
Person / Time
Site:	Perry
Issue date:	02/03/1992
From:	Lyster M CENTERIOR ENERGY
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20092A430	List: ML20092A426 ML20092A439
References
RIII-91-016A, RIII-91-16A, NUDOCS 9202100111
Download: ML20092A426 (38)

Text

W-l

- GMt c

y w

.,a 4

7CW m. CLEAR POW", a hian Address.

PO BOX 97 Michael D. Lyster D

, F C"iO 44081 VICE PRESIDrNT - NUCLEAR

'16) 259-FT Fel "ary

.2, 1992 a *I/01E-0388L g

- O S.. mca '

torv Commission t

Document CL s

Vashings,a, r,

). 35 P e t.,, Nuclear Power Plant Docket No. 50-440 Response to NRC Confirmatory Action Lett.er Dwar tiri This letter is subritted in response to Confirmatory Action Letter (CAL)

RIII-91-016A, date tanuary 3, 1992 (PY-01E/CE'. 0424L), which discusses commitments regardi., the Circulathq Vater System pipe rupture at Perry Unit No. 1 on December 22, 991.

Fo,tloving the_ December 22, 1991, pipe rupture and subsequent reactor scram, Perry management per unnel drafted a recovery plaa to determine tb extent of damage i. rom the ereat, evaluate equipment malfunctions and ensure that routine recovery activities were completed.

Daily rtaff meetings v-~e conducted to monitor progress en recovery plan ac.tivities.

Ar. Augmented Inspection Tetm (AIT) was dispatched to the Perry site on December '!2,1992 to respond to tne event.

On December 24, 1991 CAL-RIII-91-016 was received. This CAL documented commitments regarding actions to be taken prior to making a mode ::hange from cold shutdown. On January 3, 1992, a second CAL, RIII-91-016A, was received closing out the previous CAL dated Decembst 24, 1991, and don:umenting additional commitments associated with pre-startup and post-startup activities. CAL-RII-91-016A also included an acknowledgment by Region III staff, that designated root cause evaluations and corrective actions specified in the Perry forced outage recovery plan had been completed. After notif>ing Region III management of completion of the remaining committed pre-startup activities, Perry commanced a plant startup on January 3, 1992.

y

'rovided in Attachment 1 to this response, is a brief description and

~

chrorological sequence of events for the December 22, 1991 circulating vater pipe rupture. ' Attachment 2 provides a response to each item discussed in the

-January 3, 1992, Conf 3rnatory Action Letter.

9202100111 9202Or2 PDR ALOCK 05000440 4

n S

PDR 4 i

}

/{ v

- twowa compones

~ O!L #0nd fiet 0C !"Jmtc! ag t

To'eco Eamor

/

Document Control Desk PY-CEI/01E-0388L February 3, 1992 Should you have any additional questions regarding this response, please.

contact Mr. K. P. Donovan, Licensing and Compliance Manager, at (216) 259-3737 extension 5606.

-Sincerel,

)k.

)y-p Michael D. Lys r HDL RVG:ss Attachments L

ces NRC_ Project Manager Region III Administrator NRC Slesident Inspector Office

+-

(

e.

3 1

ATTACHMFKf 1 EVFXf DESCRIPTION AND CHRONOLOGICAL SEQUENCE OF EVFRTS l

l t

i l

I-l I

I.

t.

PY-CEI/01E-0388L 4

Attnchment 1 Page 1 of 3 EVENT DESCRIPTION

SUMMARY

AND CHRONOLOGICAL SEQUENCE OF EVENTS At 0138 hours0.0016 days <br />0.0383 hours <br />2.281746e-4 weeks <br />5.2509e-5 months <br /> on December 22, 1991, reactor power was increased from 99 to 100 percent power upon completion of a weekly surveillance test.

At 0152 hours0.00176 days <br />0.0422 hours <br />2.513228e-4 weeks <br />5.7836e-5 months <br />, sn annunciator was received for low circulating water chamber level.

At 0!$4 the Control Room received reports that the motor and diesel fire pumps had started and that the start-up transformer deluge system had initicted.

It was also reported at that time, that a large vapor cloud was seen in the vicinity of the Unit I start-up transformer.

At 0157, Control Room personnel

<.bserved that the cooling tover basin level was rapidly decreasing and that pump amperage and discharge pressure vere oscillating considerably for the existing Circulating Vater System (N71) configuration. Decreasing vacuum in the "A" auxiliary condenser was also noted.

At 0200 hours0.00231 days <br />0.0556 hours <br />3.306878e-4 weeks <br />7.61e-5 months <br />, the-Centrol Room Unit Supervisor-(US) ordered a decrease in reactor power to 80 percent. This action was taken with the assumption that the "A" auxiliary condenser could be isolatea to stop the system leakage. The Control Room personnel thereafter noticed that vacuum was also decreasing in the "B" auxiliary condenser. There were subsequent reports to the Control Room of water in the transformer yard and Turbine Building.

Based upon the above considerations, the US directed entrance into Integrated Operating Instruction (I0I) - 8 " Shutdown by Manual Reactor Scram." Reactor core flow vas reduced and a manual scram was inserted at 0205.

~At approximately 0210 hours0.00243 days <br />0.0583 hours <br />3.472222e-4 weeks <br />7.9905e-5 months <br />, a plant operator reported to the control room that a massive leak exists' at the 36 inch circulating water inlet to the heater bay at the 620 foot level (located in the yard area immediately behind the heater bay). As a re::, ult, the Unit supervisor ordered the "A" and "B" circulating water pumpr secured.

Reactor pressure was being controlled by

-opening the steam bypass valves in accordance with Plant Emergency Instruction (PEI)-B13, "RPV control." These valves were used until the reactor pressure had decreased to approximately 700 psig. At 0224 hours0.00259 days <br />0.0622 hours <br />3.703704e-4 weeks <br />8.5232e-5 months <br />, the outboard Main Steam Isolation Valves (HSIVs) were closed because of the imminent complete loss of condenser vacuum. The "C" circulating tater pump was also secured.

Reactor pressure control was then transferred to the Safety Relief Valves

._ (SRVs).

At 02S9 the Shift Supervisor declared an Alert due to reports of rising vater i

level in the Intermediate Building, Auxiliary Building and Turbine Building j

. heater bay.

l From 0222 to 0657 hours0.0076 days <br />0.183 hours <br />0.00109 weeks <br />2.499885e-4 months <br />, 50 individual manual SRV cyclings were performed.

Reactet Core Isolation Cooling (RCIC) was used to augment the SRV pressure L

control. -As a result of the above actions, reactor pressure was reduced from 674 psig.to 128 psig.

Both Residual Heat Removal (RHR) pumps "A" and "B" were operating in the suppression pool cooling mode during the SRV cyclings. The "A" RHR pump was eventually shifted from' suppression pool to shutdown cooling mode at 0737 hours0.00853 days <br />0.205 hours <br />0.00122 weeks <br />2.804285e-4 months <br /> to assist in Reactor Pressure Vessel (RPV) cooldown.

l PY-CEI/01E-0388L Page 2 of 3 The Motor Feed Pump (HFP) and Reactor Core Isolation Cooling _(RCIC) vere used for reactor level control for most of the transient. While utilizing the SRVs for pressure control, the plant experienced six Level 3 (178 inches above the top of active fuel) actuations and nineteen Level 8 (219 inches above the top of active fuel) actuations due to reactor vessel level shrink and svell as the SRVs were actuated. The Level 3 actuations resulted in scram signal initiations from the Reactor Protection System. No rod motion occurred from these Level 3 actuations since all rods were previously inserted during the manual full scram. The Level 8 actuations resulted in the tripping of the HFP and subsequent failure to restart after its 15th Level 8 trip at 0359 hours0.00416 days <br />0.0997 hours <br />5.935847e-4 weeks <br />1.365995e-4 months <br />.

RCIC vas again started for level control at 0404 hours0.00468 days <br />0.112 hours <br />6.679894e-4 weeks <br />1.53722e-4 months <br />.

The initial NRC notification regardinF this event was made at 0311 hours0.0036 days <br />0.0864 hours <br />5.142196e-4 weeks <br />1.183355e-4 months <br /> to report the Alert declaration.

Follow-up notifications were made at approximately I bour intervals thereaf ter.

Additional information was transmitted in response to telephonic information request by Region III and NRR personnel. Required notifications to state and local officials vere also made in a timely manner. The Alert was terminated at 1151 hours0.0133 days <br />0.32 hours <br />0.0019 weeks <br />4.379555e-4 months <br /> on December 22, 1991 -

L i

PY-CEl/01E-0388L Page-3-of 3 CHRONOLOGICAL Srot!ENCE OF EVENTS Circulating Vater System Rupture December 22, 1991 0152 - Annunciator received for lov Circulating Vater chamber level.

0154 - Automatic start of Diesel Fire Pump and Motor Driven Fire Pumps indication of Deluge System initiation on Startup Transformer.

0200 - Lov pressure indications on Circulating Vater Pump discharge pressures-

-Cooling Tower Basin low level alarms; major rupture identified on Circulating Vater System and cavitation reported.

Operators reduce power to 80%.:

0205 - Reduced recirculation flow to 52 HLBS/IIR and initiated manual Reactor Scram in accordance with-I01-8.

0210 - Plant operator reported leak in 36 inch circulating water inlet piping to Auxiliary Condensers.

Secured A and B Circulating Vater Pumps.

0224 - Manually closed Outboard MSIVs; established pressure control using Safety Relief Valves.- Level was maintained using Hotor Feed Pump.

Circulating Vater-Pump C was secured.-

0259 - ALERT declared in accordance with Emergency Plan.

0311 - NRC notification made to report Alert declaration.

!~

0400 - After level 8 trip caused by SRV cycling. HFP failed to. restart.

RCIC used to maintain RPV level.

0737 --Shutdown Cooling established using RilR loop A.-

1107 - Entered Cold Shutdown.

i L

- 1151 - Terminated ALERT; entered Recovery-Phase..

G s

~

f ATTACliMENT 2 RESPONSE TO CONFIRFATORY ACTION LETTER (CAL) RI??-- 41-016A l

l l

l l

l

PY-CEI/01E-0388L i

Attachm:nt 2 Page 1 of 2 RESPONSE TO CONFIRMATORY ACTION IITTER (CAL) RTII-91-016A CAL Item 1 Prior to startup, instrument thc auxiliary circulating vater system inlet fic.nge and the new base plate to measure any movement.

Response to CAL Item 1 This activity was completed on January 2, 1992. The referenced instrumentation was installed under Vork Order (VO) 92-00018. As stated in AIT Report No. 50-440/91026 (DRS), this instrument vill remala in place until the analysis referenced in CAL Item 3 is completed.

-CAL Item 2 Determine quantitative acceptance criteria for movement-of the fiberglass to steel flanged portion of the auxiliary circulating water piping prior to startup.

Subsequent-to plant startup,-if you determine that these acceptance criteria have been exceeded, proceed with an orderly shutdown.

Response to CAL Item 2 The acceptance criteria for piping movement-is included in Temporary Instruction (TXI)-0131. This instruction includes the maximum readings for the installed instrumentation discussed in CAL Item 1 above and the monitoring frequency for these instruments.

.An Operations Standing. Instruction, dated 1/3/92, contains the required actions to be taken in the event that the acceptance criteria of TXI-0131 are exceeded. These actions include a verification of failed acceptance criteria prior to initiating a plant shutdown.

CAL Item 3 Vithin 30 days of niaking the initial' mode change, provide an analysis of the stresses in those portions of the auxiliary circulating vater piping system potentially involved with, or affected by, repairs and pipe support modifications.

l Response to CAL Item 3 The requested analysis is included in Enclosure 1 to Attachment 2.

CAL Item 4 f

Vithin 30 days of making the initial mode change, submit to NRC Region III, a formal report of all significant issues involved in this event including short l

term and long term recommendations.

l

._. - ~

PY-CEI/01E-0388L Attachrent 2 Page 2 of 2

' Response-to CAL Item 4 1The requested report is included in Enclosure.2 to Att.,chment 2.-

CAL Item 5 Prior to the end of the refueling outage currently planned for March 1992, make-any. modifications to piping and pipe supports which are indicated as necessary, if any, as a result of the analysis addressed in Item 3.

-Response-to CAL Item 5 Any required design changes identified as a result of the referenced analysis

-vill be completed prior to the end of Refualing Outage (RFO) 3.

[.

l l :.

i I

\\

i l-j -..

o.

ATTACllMFNr 2 ENCLOSURE 1 AUXILIARY CIRCULATING VATER PIPING SYSTEM ANALYSIS

~~

PY-CEI-OIE-0388L Page 1 of 6 AUXILIARY CIRCULATING WATER PIPING SYSTEM ANALYSIS 2.

OBJECTIVE.

-To demonstrate-the long-term desiga adequacy (both piping ano lsuppotts) for the above ground portion of the N71 Auxiliary

' Circulating Water Piping.Systsm; with sufficient inherent margin to preclude,.with a high deg ee of confidence, future catastrophic piping failures similar to the December 22, 1991 event.

81.

BACKGROUND

.As part of the root cause ev3luations~, near-term corrective actions and follow-up activities assocbrad wich the December 22, 1991 event, the following were. performed and/or concluded:

l'.-

Laboratory analysis of the failed bolts of anchor support IN71-

-H0013 (see Addendum A) concluded that nuts on all four-(4) baseplate bolts were not tight during system operation prior to the pipi.'q: failure.

2.c The'same.laberatory analysis concluded that-the fiberglass

-piping catastrophically failed.first, with subsequent failure of all four bolts due to-extreme overload _ caused by the water discharge.

The primary basis for'this conclusion isLthe severe deformation (bending) present in the: failed bolts.

Refer to l

Addendum B for' photographs of the-failed bolts which have been-sectioned.

3.

Anchor supports 1N71-H0013 and 1N71-H0021'(inletiand outlet piping,-respectively) were redesigned and modifications field implemented during-the= forced outage via' Design Change Package (DCP) #91-0208-to significantly-upgrade baseplate anchorage ~

strength and' resistance to loosening.

Drillco Maxi-Bolts (3/4"

' diameter) were'now used for this application (replacing the previous Hilti. Drop-In anchors),.which have the following desirablo design-characteristics:

" Ductile" Failure Mode:

The bolts are designed per the ductile (i.e.,

steel fails first) design criteria of ACi-349, Appendix B (Steel Embedments).

Design / ultimate l

loads:for such. anchors are typically substantially larger 1

ar.d more consistent (less scatter in-test data) than for the same-size concrete expansion anchor (such as a Hilti Bolt).

l.

L e

L

PY-CEI-OIE-0388L Page 2 of 6 II.

BACKGROU_ND (continued-3.

(continued)

High Initial Bolt Preload:

Bolts are 1 stalled with high preloads (approximately 80% of yield stress which is about 85,000 psi or 20,000 lbs/ bolt).

This provides significant resistance to anchor / baseplate loosening.

Fefer to Addendum C for an engineering sketch of t?

tedesigned support (IN71-H0013 presented; 1N71-H0021 similar).

4.

Consistent with confirmatary Action f.etter CAL-RIII-91-016A, displacement monitoring instruments were installed prior to startup as follows:

Horizontal displacement (N-S, axial direction of steel piping) of the steel piping flange at the fiberglass inter-face is monitored via a dial indicator.

Called Dial A".

Vertical displacement (up and down) of the steel piping flange at the fiberglass incerface is monitored via a dial indicator.

Cailec Dial "B".

Horicontal displacemeat (.~ ~ 5 and E-W) of the baseptate of

" anchor" support 1N71-H0013 (located approximately 8' south of the fiberglass-steel incerfaca) via a ' scratch pad" installation, hefer to Addendum D which provide. an engineering sketch of the installed tamporary instrumentation and supporting frame.

Refer to Addendum E for plots of Dial Indicator "A" and "B"

readingr which have been recorded (per TXI-0131) since January 2,

1992 (startup)

For reference purposes, the recorded displacements are also plotted against variation in recorded 371 pipe temperature.

As can be seen, there is general trending between the two plots.

Concerning the baseplate scrarch 'ad for anchor IN71-H0013, no movement has been recota-d to cate as anticipated.

5.

Cant,istent with CAL-RIII-91-016A, a displacement " acceptance criteria" tot displacement at the steel-to-fiberglass flanged interface was to be determined.

The resulting criteria was established as:

Maximum reading (N-S and up-down vertical) = 125 mils I

PY-CEI-OIE-0388L Page 3 of 6 II.

BACKGROUND (continued) 5.

(continued)

For the technical bases for tais acceptance criteria, refer to Addendum F,Section III.A and Appendix I.

Note that Appendix I,

under ANALYSIS RESULTS, indicates these initial analyses were tentative pending review / verification.

This effort has subsequently been completed by Gilbert / Commonwealth, Inc.

(G/C), plus the additional analyses of Section III in essence replace the initial evaluations since they are more definitive in scope as discussed below.

The pertinent considerations from the above were factored into the (see III below) that were performed additional piping analyses _

pursuant to CAL-RIII-91-016A.

Ilf.

ADDITIONAL FIPING ANALYSES Note:

Refer to Addendum F for additional details of the analysos.

Addendum F is a summary technical report (G/C Report EA-182, "N71 Pipe Rupture Evaluation") from Gilbert / Commonwealth, Inc. who was contracted by CEI to assist in the follow-up technical eval 6ations, Additional analyses were performed to achieve the stated objective of Section I above.

An overview of the scope of these additional analyses is presented as follows:

1.

Expanded Model The truncated model which was used to develop the displacement acceptance criteria of Section II.5 above was expanded to include the additional N71 steel piping to the auxiliary condensers, as well as the fiberglass piping to the tie-in (underground) with the 12' diameter Fiberglass Reinforced Plastic (FRP) piping.

This was done to ensure enveloping of potential influencing factors of any significance.

Further, because of the importance of ensuring the functional integrity of the anchor supports (lN71-H0013 ar.d 1N71-H0021), a detailed finite element model of the support was constructed and utilized in the piping analysis.

For specific details, refer to Addendum F, Appendix II/Part A.

G

.-m._

-_._,m "e;

y PY-CEI-OIE-0388L Page 4 of 6 j818.

ADDITIONAL PIPING ANALYSES (continued) 2.'

Hydraulic Loadings j

l

-In addition'to deadwelght, pressure and thermal loads on the i

piping system, hydraulic loads were also determined.

Even though initial judgements were that these loads are relatively insignificant, they were calculated to obtain added confidence that. flow-transients were not a credible root cause contributor of the piping failure.

The hydraulic loadings which were considered included both steady state impulse' loads (due to momentum changes at elbows) and flow transients due to pump starts / stops and valve-openings / closures).

The details are

- s presented-in Appendix III of Addendum F.

'The final results confirm the initial judgements that hydraulic loadings are very small (i.e.,

less than 5% of the pressure load).

Nevertheless,-for completeness, these loads were conservatively applied to che analytical model and combined with the-other loadings.

3.

LOperating-(" Design") Case

-Thefinlet and outlet piping analytical models (as described above) were separately executed for= maximum pertinent operating conditions of deadweight, pressure, thermal and hydraulic loadings.

4.-

Displacement

(" Target") Case-Further, for added assurance of demonstrating ample system margin and functional integrity, an artificially imposed

- " displacement" case was also executed.

This case forced displacement within the piping-in?et model corresponding to movements of-0.125" (vertical) anc 0.135" (N-S) et the s teel-to-r'ibe r gla s s. flanged :inte r f ace.

These target displacement values were obtained by extrapolating maximum g

recorded. data-to date (see Addendum E) to the estimated full ll range of-system thermal conditions.

p The-displacement case-analysis is also intended to more definitive'.y establish instrument monitoring acceptance criteria for-both the'FRP piping and thr. anchor support.

l

't PY-CEI-OIE-0388L Page 5 of 6 8V.* ANALYSIS-RESULTS 1.

Operating

(" Design") Case The analyses for both the inlet and outlet N71 piping demonstrate ample margin for both piping and supports.

With regards to the FRP piping, the maximum calculated stress is 2232 psi, resulting in an additional facter of safety of 1.7 against the long-term strength for FRP pipe of 3800 psi.

Anchor support loads were well below allowables.

2.

Displacement

(" Target") Case Maximum FRP piping stress for this case is calculated to be 1948 psi, or about a 1.9 additional factor of safety compared tc the 3800 psi long-term strength.

For the anchor support, the full range of target displacement values were not quite achieved (approximately 85% of target values-for the " functional-check" case).

However, this is not to 11aply that anchor support. loss-of-function would immediately occur at the target displacement values.

.The limiting componene for the anchor support's strength is the Drillco Maxi-Bolts. -As discussed above in Section II.3, Drillco Maxi-Bolts areEductile which means that the full. strength of the steel can be developed (i.e.,

any bolt overload will cause steel yielding and eventual ductile fracture after significant deformation).

Since the piping displacements in question are thermally driven

-(and thus limited) and the Drillco Maxi-Bolt stee] has an elongation capability of approximately 20% at fracture, it follows'that minor additional displacement to meet full target values (from 85 to 100%) will not mean functional' failure of-the support.

Further, the analyses to date, have shown relative insensitivity of the FRP piping to displacements of

.the. magnitude of the target criteria.

Thus,'very slight increase-Infpiping displacements due to Drillco Maxi-Bolt yielding to reach target piping displacement values, would not be of any significance.

It should also'be'noted that the calculated limiting diaplace-ment values for the anchor support envelope the recorded N71 displacements _to date, Addendum E, with ample margin (approxi-

-mately 1.6, minimum).

Refer-to Addendum F for more details of the analytical results.

4 9

PY-CEI-OIE-0388L Page 6 of 6 V.

CONCLUSIONS 1.

Long-term design adaquacy of the subject piping, with respect to system functional integrity, has been demonstrated for the current system configuration.

This includer demonstrated capacity (with margin) above N71 piping displacements recorded to date.

2.

As discussed within Addendum F (Section IV), the Drillco Maxi-Bolt components of the anchor support achieve approximately 60%

of the target displacement criteria when conservative standard design allowau; 2s are used.

Although system functionality has been demonstrated (Item #1 above), in a desire to provide additional conservatism and still further assurance of system integrity, as well as to alleviate concerns over a repeat catastrophic FRP piping failure, an anchor support redesign will be pursued for both inlet and outlet N71 piping.

Planned implementation for this design change will be prior to exiting RTO-3.

i

O ATTACHMENT 2 ENCLOSURE 1 AJDF'IDUM A (8 PAGES)

. _ - - -.. ~,

q a

A J

csw n m on-ex4 -

M.E M'O R A N D U M'

- To - J. P. Eppich acow PYE110 raOa M.S. Bricavsky cart 1/15/J2 PMONc ' 4371$

aOOaE33 suesset Analysis of Failed Bolts from the Sup; ort System of FNFP Circulation Water Piping Supply Line to the Auxiliary Condensers - Final Report s

- Four' bol s and eight nuts were supplied for failure analysis.

The analysis of the bolts and nuts brought us to the conclusion that the anchor.

type support of the pipe had a lateral mvemnt which caused a displacemnt of the pipe. -TN exht of the displacemnt could not te determined.

The laboratory analysis of the bolts and nuts indicated that the 61ta failed as

'a result of the overload due to pipe failure.

Laborate m ch m. O n:.

'Four failed bolts and eight nuts were submitt+.i for failure analysis.

Most of-the bolts and som nuts were cut longitudinally by FNFP personnel.

The bolts and nuts submitted ere part of the support /.he ciztulating water

piping supply line to the aM14m/ condenser from the cooling tower.

The aupply line:ista-36" diamter fiberglass pipe connected to the steel pipe approximtely L E ' from the sup; ort.

The: fiberglass pipe coms _out from the ground 2tnd is connectM to a horizontal run of steel pipe.

The falure occured at the fiberglass eltow.

~ The four failed tolta had teen secured by liilti Drop-in assemblies emtedded in a -

concrete base. : Each tolt had two nuts. :A plate was supposed to raet on the L

lower nuts and be held down by the upper nuts. To this plate another plate was.

t l(

twelded.. To this second plate a stand made of a pipe was mided and the 36" steel pipe.was welded in turn to tM post. That structure constituted an anchor support for the pipe which was designed to prevent pipe movemnt at this point.

The following oteervations were made:

L1.

Two tolts (NE and NW corners) failed below the lower nuts.

J 2.--

Two bolts (SE and SW corners) failed between the nuts, within the plate-thickness, j;:

-32 The threads of three out cf four bol*s were hamerad flat in heten the nuts (Fig. 1).

L All four bolts failed in ductile mde with significant-plastic tending.

R

4. -

p.

3EC-E el L

-3% 11 gtC#h$on trmG9

x -.

Page 2 5.

tio signs of fatigue on tM fracture surface were found.

6.

Fatigue cracks were found-at other 1ccations on the bolts with indications of corrosion assistance (Fig. 2).

7.

Observations made on the nuts showed that only one nut of each couple was in contact with the plate.

8.

CMmical analysis (Table 1) shoued tlut nuts and tolts were nnde of carbon steel.

Very low silicon and aluminum content indicated that rimed steel was used.

The Hilti Drop-in assembly was made from low carbon rimmd steel with high sulfur content added for mehinability.

Discussica and Conc hsien The oteervations are sumarized in Table 2 and Figure 3.

TM findings indicate seural significant facts. -

a.

TM nuts were not tightened down, which allowed tM plate to mve (see fig..

3).

b.

The plate had a significant lateral mvemnt, which was proven by the signs of friction between tM plate and nuts and by the hammred threads, c.

The lateral novemnt of tha plate caused fatigue of tM bolts and, possibly, cycling loading of the pipe by allowing the steel pipe to n:ove with the plate it was welded to.

d.

The mtallographic analysis of tM bolts confirmd the presence of fatigue cracks filled with iron oxide at locations other than the fracture surface.

Analysis of one of the cracks was performd on SEM by mapping the imn and oxygen contenta. As it can be seen on Fig.

4', the crack is filled with iron oxide. That confirm the corrocion fatigue origin of tha crack and its slow propogation.

e.

If the bolts had failed prior to the pipe failure in the fatigue nede, the failure would have been certainly located below the lower nuts with no significant plastic deformtion. The severe bending of all four tolts leads us to believe that the bolts failed due to overload but not due to fatigue, Bssed on the laboratory arnlysis we cam to the the conclusion that the fiberglass pipe failed first and the water discharge caused the overload and failure of the bolts.

b Bevieued by j/a - d b ^ a -- - -

Dats 2 /rc, /992

~'

Attachmnts lSD/bju ec: R;M. Kantorak R. F. Kator.a R. J. Standish R.J. Tadych

. ~...

.... - ~..

i Tabl. 1 Analysis of failed bolts from the support system of P.NFP circulating water piping supply line to the auxiliary condensors Chemical Composition of Bolts and Nuts Chemical composition, wt :

- Location

- (Corner)

Description C

Si Al Mn P

S NUT

'0.039 0.005 0.007 0.37 0.007 0.040 N.E.

BOLT 0.27 0.040 0.007 0.40 0.010 0.046 NUT 0.040 0.005 0.099 0.36 0.007 0.35 N.W.

BOLT-0.27 0.041

.0.007 0.40 0.009 0.039 NUT-0.037 0.006 0.006 0.38 0.007 0.043 S.E.

BOLT-0.27-0.040 0.006 0.40 0.009

.0.035

. NUT 0.044 0.006.

0.008-0.37 0.007 0.000 S.W.

. BOLT 0.26 0.039

-0.007 0.40 0.009 0.037

- Hilti

- Drop-in

-0.067 0.009 0.003 1.46 0.078 0.28

- Assembly E

Table 2 PfiPP Circulation Water Line Failure Stznery of ti.e visual observations.

Threads Upper Hut Lower liut I

Corner Failura Location Condition Condition Condition SE Between Upper &

Ilammered on Shiny on the Rusted and Pitted.

Iower liuts one Side.

Interface w/ Plate.

11o Signs of Pitted.

Mechanical Friction.

'SW Between Upper &

Ilammering Shiny on the Rusted and Pitted.

i Iower fluts llot Found. -

Interface w/ Plate.

tio Signs of Pit!ad.

Mechanical Friction

(.

IlE Below Lower 2iut, llammered on Rusted and Pitted.

Shiny on the Above the Two Sides.

11o Signs of Interface w/ Plate.

Concrete.

Mechanical Friction.

Pitted.

1H7 Delow Lower liut, Ilammered on Shiny on the Rusted and Pitted.

Above the One Side.

Interface w/ Plate.-

tio Signs of concrete..

Pitted.

Nachanical Friction.

e*

i.

6

r; l

I l

I I

a i

A t.

s,

.b

.* wr,.

,u

...:4 1..,.

s-t s

• g; c w.

. _.i t..

s.-

s-

%,. 9

,., 2 c.....

w.

. c,T t e

w.. _

_ ~.,,. ' Q ' '.

t-.

6'4..

I I

> :- *w w....s q.

a

p. *

- s.

g j

~

l 4

w

- )

o 10;<

l Fig. 1.

t-PNPP Cir:ulation Water Line Failure P

L l

Crossections of the bolt with threads ccTpressed (bas ered).

i l

l l

J e

l e

e ev--

a

.w-wv.,,.=.-e-

--r--

ww.?

--p w-

'e-

~

,%.; ~< : 3. *

.y,T.g,

x '. '

, p l*),4.'~,'. [

N*.

c.

+

m..*..

,.y. a.. 4.

• s',. ~

.., c. J. *...... -

a. y,

e~

zO.. ; 4._

., 7:,.,. "s *.

...'e..,

w

. 2... v.

s s-

\\.2 n ' t ;...

c..,;,.,., c.

4..,

• i a'

.. ^.

. ~..

t 5

.,, ;. e-- s,,,,.

't

.~

~*

.. s.. :

..~....:..,:

.. s

. s. u..

.., q.<.

,,,,,,34

e.,-.

'fr;:,,d,'3a v. c,

4.c,s.s,

., > :.~

'$m %%9,.; W".,

,. '... t,,.

. W.1. *.. l; 0. '

8 *-

. a.

$fe.,:,*;'.x..

'*Q.'r,N..-

. ' ~.,.. * \\.-

?:'\\ %'i AYN ':<*.Y'..';t* vl? cri '

4

.." p-4 4..

..,:a ':*. -.

.s :

• e }v:.rgo.>.~ h...,.;: 7 N.-

s s.

o

• .4,'.h.,./.1,'l.kL.

+., #.. f' ' ' '. Y.,..,.

• a(. '.'.

d Y,

• f[. ':;,f.r'.% 1.

u ;..~ ?,%, y '., ', '(Y *,* 4.,1....

. r ' 4n'.v 'a

& D'd.',M, to *y*m <

. r o

.* af.

. s

• Y,i a, - dN ~ E.'; Y $ [*- 5.. $s'rY;,b **f',';' gf. ;,,.,,

• .'*w.

[e f t

. b.'A*'* ?,

o i

b 4

. 4

,y g.

v-( b,,.

h,<

.R..,'.,,,

...x g.

I

. f l/ }v 1

'g,

t ? -

~-

,.:.c s,

c',

A

~

J' r-v-

i gm

• g

....m.

s s

g]

.Jr -. -

g

. 4

. ~

, &.4&.1

'Y 4 /

3 x

hCCw Fig. 2.

PNPP Circulation Water iine Failure Typical corrosion fati?m crack.

NW NE i

7 H.

H H

/ )

l J.

t j

f I

,J NNNN, t ' e:s Ns w.

l l

l g

l 1.l

/ p...

.MA#...

k.

u. v.

__.. 4;w.-...

..(

l ora //-/ /r//

./ / g f,y f_ j' y l

u

...._..N,_.__.

I I

1

,l I

j._. __.l.

l

,g / _

w///// A / / //A __.

/

-4 6 6. 46 ry V////:

..i W

5 7>

ML**1 i

r

. _A i

i Qs,g

-Q L,,,,,

i i i i : i ! +

i i

t I i i t i ! i ;

W i i ' I

! l l

l 1

i

• i i

.i e

i I

i

, i i i

,i t

i i i i.

i i :

i i i i t

i,,

.,i t i i

i t ii i,

///Q,/_/,/ ~

__///_ 4.4.,L / // 1

• t > >

,*ti+

i.

i i

i,i i i i i5 - i i i-, i i i i i -

i i i i

. ? !

8 i

i i

l I 1 ) { i l i l.

i l 1 i

,i

, ;, i e

l i t. 4 e t,,,

i j

i 6 i i l l l 1 I l

j

}

I i

e i

'l I

8 e !

t 4

5 t

s.w.. __

...._S E--

H...TH R.s A_/D5._ARE_ tit. _M.M E R C D F\\AT..

Fig. 3..

~

PNPP Circu.lation Water Line Failttre

-Pictographic presentation of the observations stmnarized in Table 2 and showing the location of the plate in between the nuts.

/' _ -

i)

4 i

Fig. 4.

PNPP Circulation Water Line Failure Stress corrosion crack and chemical Q

... ; d[.'.b.

Q, ',t..,,,. 4 ' i, /

• elenents distribution.

,/

.' /

(

A. Optical photograph of the crc-k at

.S

• ' ~,.

nugnification 50x.

B. SEM photograph of the part of the

, *,, ' +h.",. '. '2 ' '...

l 1

,f crack A at 480x.

m,.

. 3. 934 '_.c..

n C&D. EDS map of oxygen and iron.

i 5

t,

'. $nx$.,

M, s... w.,.M. E f: M.

.n[. v,,-..

cf. 9p...

@,7 m...,s.. L w.g / 7

.1 y..~.,.

a.,

i s.

. m. ~.

....a 2.e.

.~

uf m.

.. n,t... m., '. 4.,e.

9~.7.,. w

,. y..

..:'u.

l i

/

t.'

. av..

. ; r. ;,,.. (,.r'* *.

i

,k ', w.

s

. p. ;>

. G;N.~.42

- s 2

v.~ s c. W4-,q,, t.

. '.. :'~ ::

g '...

i

~.

. s..%,<..

.. c..

~, s

.,s-m.

n....w

.o

.s

. y.

u r-ef

'WE '..,.

~ v.,o YM,-v

}'*N* %' Y.,/.1I.e

'. *. '. '.. ([},..

. ^

• 6.. QM *.

s

... M.,-. ; :..N:c.,.

j*.

1 WG<

V:

et.

y

q...

?,.

a.., '.. = ~. y.

a l

~

.~

.,a:.<:.x x

.s l

.%v.sy

~

.,,. y,. w..

.~.,

E'd,.. -5'[.. ;N && y:.;.7.r ;-@.k.)

1

. ~ '.

w.

i

... ' g.,.,., m..;. '

~

~.

p 3.g,. ;. :..p.

.-=w

\\

a.;.-.

'n?.,9.d.,!.,~ *N'$, N...s '.h:..i. ' ;

.s

'.'...*..l.l v

l

..a v

n.y m..w.....~...:.

. ~%.

g..h....

ng-4....W:....y..

.'...o: a.

m..

. a...a..

oggg a n.

Y IRocJ N Y '- l y

• a

y.. s &,, v s c. ; ~.. t;. -:m.=

1

^

-G

=.

..,;i.- w w w.m p.

.C.,,

s

,V Q :. Q.%:.' f>.y '.L l

y e

- -2 w

e,.

I

.? y..,~ - >,.,,,-.. g.3 y-q._n n

- - ;;., + ;.

Q

. ~.

L l

~. - :-

cg

,.,t.,

,./-f.,v.

,.,;,' M,

. ~. ;.w,. - 2..

s O ~. M

.w c,.'. L T :

l

< - $], - g.

s.

% & *. /F

. pf Y ?., K..,: f q

y-...:,:e

.. y.

n".,4 %.a A._

,92.,,--D. Q.

@s., p }.

.;~i :.1 n

ai.

.u

. q.o y.-s y y.....,.

.e,*,

s y

-.,,., R.:. A, <. <;..

T. ^ ~' _

.-- : o

. 4,c. y.; g y 'i. %.y :~.,?:.L y e, n

/

2

..a

... s J:y> <.= f.^._ -. :.m

,y

.~.

• a y; y?.-~,e.y..

y. '.

. s-;

e.~..

c y,:'2,,b.;* a n.%

'g

' lr:,:<.[ :' -

't_

g e

b s.

3

.e p.

• f j,' - [ ' '. --

.[,, s - d '.

,l-

= '

~.;l'%-

.<.e.f*6.y

~

%..* ', ; i,..

- {*..,m

. - Q., - '"

' 'y] '. j 7,, ', ' ].

2. *';. >.

a 2-o q-

,3 J..: > *g, '...,q..

,. ( *s..'.,. f f. g 89

.l

(.&.'? D Y.

,L - N.'-. h. h

'9

• r p

I

• l

ds

[

.- %f/* 4; 8'

\\//o Yh*'*@> *?#$

/

'I

/'/// /

g['3 [4 IMAGE EVALUATION

• (p

\\//7

'i. Q TEST TARGET (MT-3)

$y%>

//7Q l.0 i RA En c tu p!1r2=

I gg bb U

l,l p l.8 im 1.25 1.4 1.6 4

150mm 6"

d %zzzz

/f4%

r, p. g, y,,/ 4,.

.,,,s////4

.m oe o

e r/

t,g 46 i

1-i h. _._ ___

____ __ ___ ____, _,, -g,; Y]f. __

~ ;

{ :

9 a.,-

l' :

t ATTACHMEN't 2

l. c ENC?.OSURE 1 ADDENDUM B (2 PAGES) u

(;

ll

?

h,__.

TAR 91-516 hev. 1 Fage 3 of' S TEST / ANALYSIS RECUEST h

b OTE. ExcEEP T-TRcpi T/nd 91-514; VEN. l

~)

. w

. 75MaY v

' $ k._

a ar --t.

u..

s 1,MM E

. >s e n-t a

2

[L i.

i

.w.

l

~

/

=

=<

~

e v,

5 3

$.';,5. 5

~

i :. C;. :

\\. \\

g'h C ' _=

e

'6-5 A

l ',

E-e,9 E %=*^-

t i 2 '.\\

2-l

$ $ *"~

i.

t-k - =

,7 A..q,. "'Q y-

=

if

'l p.<,

p;. 5

,, v

- s g

J. ' - r.j l

?

.,Ni s,I:

}.-!Id s

--etj

j ji'

'}

. =.

Ihs E

.-- G -5 h

$-=

~

5 h

'E3 au m u.

_.,_ SECTIONED ANCHOR BOLT AND NUT

_i 7lf y

Wa CCPNER

~

a 35CTICNEC ANCF.C? SOLI n:D N'jT

?!E CC?l:ER

_. ~.. _ _ _ _

J

+

4 TAR 91-514 Rev. 1 Page e or 8 i

TEST / ANALYSIS REQUEST NOTE - Ex ceg? T-g var g D R.+ m-st4,

' Red I

l J

i i

I~

Th.

Q_

. : ;Q

. ?Z.,w...;.

2-i

- [;

-E

..*Z r

('

j f

f}M I

s l

4 G

j 1

-e 8

i C

3

,n 1

i m.

L-.:

T*

-e.

Y SECTIONED ANCHOR BOLT AND NUT I

S'4 CORNER g

b i

l 3ECT!CNE. A;;CHOR BOLT AtlD NUT

___N SE CORNER f

a

)

e y'

e o*,a

{

L

..__-.____..~_.-._.~..--,...-..---.-,c----

klF

' S.

[ $.:-

e r.

i l

-i l'

i I --

D ATTACHMENT 2 ENCLOSURE-1 F

ADDENDUM C-(1 PAGE) t.

t t -

f I

i I-.

I l-l I

l 1

-7 F

• F

? y

-*gp.-

19 gw,

.s 3y,.3 y_y.,p.,yy.,_,,,

7

,,py,.

l

=sittl4 titaf,$;,l#d'l h MAIP*len I lo".c A M / 3 0 A P'". I l 'a $ T/8 ' L3 OH498 TO Fff 1

a ie i.

i i

j 3G" 00 PIGL G S. E :!i"cT. A. A i

6i i

i Ce.LE T e.O I

C i i

i C!" LE T E D I

oi i

i c e t.a T e.o i

S. t i

i C E u".T S O 1

l Q l ' 1L 1 (/ A l'. G" W I A.SG

l l 1

a Ca l i I

• I iE l' 1

• k ? " 1 7 1* L:'a W / Cal) */O" @ WOLE O I A

• 3 ;,

i i

4 3 3 ccJ w cw ecTiew - M W t

.1 I

i 3/C'o C atLLCO

• 4 AK I SCLi3 08 M N 45 '/t W/t

e q s s ?

pts < t b s s '. Q '

ts.s A 3 Gs a-l 31"

(

li4-4

~~

l

. 73. ptse.

[

b yv i

os

.a i

6 cu'4.

l e

e i

,5t c:s-c

~ ico~u ? W

}

h,ys, elFe nl i

c u 4)

/

j 4 u N

1 m'

7 OCICd-DD

^

w c

t.

v.%s,oQ c=- o c=-, G@

ha e

1

,, g IS M

-f-FA

.t$

m.

....u. cw ai 5

CM)

./

T :r Tp, g, n, M34 m

4 e PAa s

+-

,7 N

,-~

c e. a i c o - A A NM t'let 3.Evit.Aase (Lit.*EIC rt i armrTam C:Breert

$WS. U$ !KjM naat -e na emia nuar

.rv s.

Pi9t Msti f

434<j 92 -Ici CCl3 MK.

IN ~Il MC l3 2y 7.

IM i

MX

.MV S

! k.

( t ',

,/

I i

a l-

.i i.

ATTACHMENT 2 ENCLOSURE 1 ADDENDUM D (2 PAGES).

l

l

~i I

-i I

i l

a L

e 4

og

$e%

.-4 Dk g

$h>

.* A N

r,

\\

,\\-

1. i

\\.-

..x

• ): '.

N

',-I'4 d'h, l

5ss

-[s 7 L.t

~ ~t

\\

r

\\

--a g,-

N s

g, N

w' s...

\\

@ n>s

'o

\\

2 3

'\\!

0 y

s Nb

/

a s

e' $

, ' ~

o

'D a

>a.

0

.3 y

d g

s f

b

-3 s

is

[.3

\\

3 _d s

\\ d" f I ip u

h a a o

a 6

1 N

(o

-+-__4su,a

~s.4+4-_A_%

e-s_.m'espm.4 m

4. J. s

.e.m.L.-e4v r-a, J 4s k _

4_4 A-.A+=

4 J

--ie44-.*L a.-4..h.A.A-a i,M,. ism &_

.,,,4

_s

-,a,.,a

__4..a.

s..

,b -

1j

- p e

-1 4'

l

(-vas)

U*

4 3

o,s s

9 2

0 0

2 0n Y-

\\

r I

Q B

we n.

i

. l-4 1

fL 'ro2 Ih

% $U J -M 1 4 M

I g%

4e, d.,

I eu d?

4- -(

1 f

^

v v

[)

e D>

@p q//

4 J:-_<<

c>

y ev

+ ~4

~

6-

-A

)IN

)

f y a

th

}

N I

4 s 2 y

)

3

,3 2

o D

l h d F 3 {

et 3

8{

N I

We4 h

2

=

J ag a ga gu i

1 a

2{

e 8

oss I

p o

m r v J

[

b1 4

eF

'b

{Q 0

0#

J

}

l (f

l

--J

&'11 L

(;4 I

(

v @

~~

u e

3 F

L b

u.

1 N

(i,

....,,,.,.a'

T-

-u..

mas-&.w-

_my-

.eu.

~ ~ ~

s.~,.-.

san.-+~ura..a..

'I.

5:

[.<

1 1w

?

e i

ATTACHMENT 2 ENCLOSU:E.1 i

i ADDENDUM E (2 PAGES) 4

$~

9 2

4 I"

A f :'

f f

. /;. _

-, ~

DIAL"B" READINGS T

ao_

70_

~

P 60_

o_

50_

X x

g 40_

30_

t y

20_

n l

10_

u X= PIPE SURFACE TEMPERATURE (F)

Z-DIAL B* READING (M!LS

~

DISPLACEMENT-VERTICAL UP)

S 0

a 0

5 10 15 20 25 30 DA~~E OF R EADING (JAN.1992)

D AL"A"READLNGS T

80_

~

70 P

60_

^^^

-/

50_

o O

40-p v

30_

r

\\jj 20_

=

z t

10_

X-PIPE SURFACE TEMPERATURE (F)

Z= DIAL"A" READING (M!LS

' 8"'^c '" '"'-" "'">

S 0

=

0 5

10 15 20 25 3O DATE O= READING (JAN. 992;

i-1 ATTACHMENT 2 ENCLOSURE 1 ADDENDUM F (27 PAGES) h t

NOTE:

Pages 5, 12, 13, and 14 of tne attached evaluation vere modified on February 2, 1992, and telecopied to CEI prior to submittal of the CAL response.

l l

l 4

e

) Gilbert / Commonwealth, Inc. eneneen ana msunanu P 0 Sox 1498 Reacing. PA 1%C31498/Telepnene 215-US 2600 Cable Gitasottielen 836 431 l

January 31, 1992 The Cleveland Electric illuminating Company Perry Site P. O. Box 97 Perry, CH 44081 Attn:

Mr. J. P. Eppich Re: Perry Nuclear Power Plant G/C Report EA-IS2, Rev. 0 N71 Pipe Rupture Evaluation

Dear Mr. Eppich:

Attached is G/C Report EA-lC2 documenting our evaluation of the N71 circulating vater auxiliary condenser inlet and outlet piping and srpports.

This analysis is in accordance with the task scope defined in Task Authorization #92-0002. We trust that this report will assist you in preparing your final report on this matter.

Please do not hesitate to contact us if you have any questions or need additional information.

Sincerely, m,

P. H. Schmitze r, P,. E.

!. i itl t

., e sc R. J. Schmehl, P. E.

)

hMjh,[.s _-

J. G. Shi'ngle r, P,(.

. Project Manager ()

a PHS:RJS:JGS:rmb Attachment cc:

C.

R. Angstadt W. C. Flensburg P0/DC J. M. Marrinucci i

cf.,.n ~, nwy a uc3 % a 5 m ustxwe w %m a wa w a m a recm %$&m hee *=ur* 'N W] 08 MO