ML18038B827

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Rev 1 to GE-NE-523-B13-01869-032, Evaluation of Indications on Browns Ferry 3 Annulus Core Spray Piping.
ML18038B827
Person / Time
Site: Browns Ferry Tennessee Valley Authority icon.png
Issue date: 03/07/1997
From: Marisa Herrera, Mcallister B, Mehta H
GENERAL ELECTRIC CO.
To:
Shared Package
ML18038B826 List:
References
GE-NE-523-B13, GE-NE-523-B13-0, GE-NE-523-B13-01869, GE-NE-523-B13-1869, NUDOCS 9703180233
Download: ML18038B827 (66)


Text

TECHNICALMODIFICATIONS SERVICES GE-NE-523-B1341869432, Rev.1 March 1997 KVALVATIONOF INDICATIONSON .

BROWNS FERRY 3 ANNULUS CORK SPRAY PIPING Prepared for Tenncssce Valley Authority Prepared by GE Nuclear Energy 175 Curtner Avenue San Jose, CA 95125 9703i80233 0 500029b PDR ADOCK pDR 8

.'e NRR 87 '97 11:SSAM GE BAR TECHNOLOGY P.

GL Nuclear Ilucrgy 2'L-NS-Bl3-OI669-032.

Rcv.l 4

i EVALUATIONOF INMCATIONS OK BROWNS FERRY 3 CORE SPRAY PIPING

" 'March'7,'1997 '-

'-'I.

/~1p S.A. McAllister, Manager Reactor Internals Management Prepared by:

K Mchta, Principal Enginccr

'Engipeerin ndL nsing Consulting Services Vcrificd by:

M. Herre,'incipal Engineer Engineering and Liccn ing Consulting Services G. L. Hayes, Manager Engineering and Licensing Consulting Services

GE Nuckar Enngy GE-AE-B13-0l869-032, Rev. 1 TABLE OF CONTENTS

1. Introduction and Background 1
2. Crack Growth Rate Considerations
3. Structural Evaluation

'4. Sparger Installation 3

5. FIV Evaluation Assuming Complete Disengagement of The Collar Weld
6. Evaluation of Leakage Impact 5
7. Evaluation Assuming Indications in Shroud
8. IGSCC Susceptibility Evaluation of Core Spray Welds II

'I

9. Summary dk, Conclusions
10. References APPENDIXA A-1 APPENDIX B B-1 APPENDIXC C-1

GE¹ekar Energy GE-NE-B13-01869-032, Res.1

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1. INTRODUCTIONAND BACKGROUND This document addresses the indications detected during the IVVI of the annulus core spray piping at Browns Ferry Unit 3 (BFN 3). Specifically addressed and analyzed in this report are the significant cracking indications at the collar to shroud weld (weld P8b) and the minor indications at the elbow weld (weld P4d). Figure 1 shows the configuration of the annulus core spray piping welds at the shroud location. The annulus core spray piping is attached to the shroud via a collar.

Figure 2 shows the core spray sparger T-box assembly including the collar. The collar is not associated with the core spray injection flow or pressure boundary. One purpose of the collar is to prevent leakage from the inside to the outside of the core shroud at the location where the core r

spray piping enters the shroud. In addition, it provides the attachment of the core spray piping to the shroud. This adds stiffness to the piping which aids resistance to flow induced vibration (FIV).

During the ultrasonic examination of this weld on the Loop C downcomer at BFN 3 plant, four circumferential indications associated with IGSCC/IASCC were recorded. The crack lengths are shown in Table 1. Figure 3 shows the specific inspection parameters for these indications. The UT data show the indications to be located in the HAZ of the core shroud itself, rather than in th' collar. This is not a unique finding, in that two other plants have detected indications in the shroud using the UT technique at similar locations. In addition, cracking in the shroud near attachment welds is not unique to this location; two other plants have detected cracking. in the shroud at locations where brackets have been attached to the shroud by groove or fillet welds.

Although the indications. are believed to be located in the shroud itself, for the purposes of conservatively evaluating the capability of the core spray piping for continued operation, a bounding assumption was made that the indications are located in the collar and that the collar is completely'isengaged from the shroud.,Using this bounding assumption, an evaluation of the resultant stresses on the core spray piping was performed. In addition, a structural assessment was performed for the more likely condition where the indications are located in the shroud.

4 I

During the visual examination of core spray piping welds where ultrasonic methods were not applied, minor indications that were oriented close to an axial direction were noted on the P4d weld. Two indications were noted that originate fiom the toe of the fillet weld at an angle of 30's measured 'C from the center axis of the pipe. The indications are both 1/2 inch in length and are separated by a distance of 3/8 inch. A structural assessment of this location was also performed.

GE lUuckar Eacgy GE-NE-Bl3l 869-032, Rcv. 1 This report describes the results of these analyses.

1

2. CRACK GROWTH RATE CONSIDERATIONS The inspection results indicate that the indications ar'e of IGSCC origin. Therefore, a key input in the structural margin evaluation in the presence of these indications is the crack growth rate. The BWRVIP Guidelines document (Reference 1 ) recommends a conservative crack growth rate of Sx10'n/hr.

The preceding crack growth is expected to be conservative for this application. The reactor water conductivity at the Browns Ferry plant has been better than the US BWR Fleet average. The coolant conductivity at the BFN 3 plant has averaged 0.09 pS/cm over the past cycle. Figure 4 shows the crack growth rate predicted by the PLEDGE code as a function of water conductivity.

An improvement of better than a factor of 2 is seen as the conductivity decreases from 0.3 pS/cm to 0.1 pS/cm. The BWR'normal water chemistry guidelines typically set action level 1, at conductivity greater than 0.3 pS/cm. Thus, if one were to assume that the Sx10'n/hr.growth rate is applicable conductivity to conductivity of 0.3 pS/cm, the predicted crack growth rate for expected BFN 3 is 2.5x10 in/hr or less.

Based on the preceding discussion it is concluded that the crack growth rate of Sx10'n/hr used in this evaluation is conservative.

3. STRUCHJRAL EVALUATION A structural evaluation to determine allowable flaw sizes based on a finite element model of the core spray line was performed and is provided in Appendix C. The anchor point displacements used in that evaluation are shown in Table 2.

The minor flaws identified at the P4d location, although mostly axial, were conservatively treated as circumferential indications. The flaw length was conservatively assumed to. be 1.4 inches. This length'was evaluated against the flaw tolerances in Appendix C and is well within the allowable flaw size of 9.8 inches for this location. The projected crack growth rate for one cycle is already considered in this allowable flaw size. In addition, these flaws have no structural impact on the evaluation performed for weld PSb.

I GE Nuckar Zscrgy GE-NE-BI3-0l869-032, Rrv.l The remainder of this section discusses the structural margin available assuming the indications at the P8 weld to be on the collar side of the collar to'shroud weld. The calculations for the projected remaining ligament at the end of one fuel cycle of operation are shown in Table 1. The projected remaining ligament is 2.5 inches. Even ifsignificant cracking is present, leaving a 2.5 inch uncracked ligament, it can be determined that there remains axial load carrying capability.

With this amount of ligament remaining, the weld would not have any significant'moment carrying capability. However, it is likely axial forces would be resisted up to the capacity of the remaining weld, thus providing additional conservatism for the evaluation.

This type of approach has been performed'for other core spray lines with similar flaws. Finite element modeling was performed by assuming that the connection of the line to the shroud has no moment carrying capability. For the most limiting load cases, the safety factor was found to be greater than 5 as defined by load capacity/axial load. The intent of this discussion is to point out the presence of axial load carrying capability which is not considered when determining the calculated safety factors.

The fundamental &equency of the annulus core spray piping with the assumed hinged boundary condition (i.e., rotational boundary conditions released) at the collar welds, has been determined.

The objective was to evaluate if any change in the fundamental &equency would pose flow induced vibration (FIV) concerns. The results of this evaluation show that by modeling the lower core spray line to shroud connection as a hinge, the natural frequency of the line changes from 8.4 Hz to 8.3 Hz. The vortex shedding &equency was conservatively estimated as 2 Hz. Since 8.3 Hz is greater than a factor of 4 away &om the vortex shedding &equency, no concern for FIV caused amplification of displacements exists for normal operation and post-LOCA conditions.

I Therefore, a static evaluation is sufficient to determine the maximum FIV stresses. Section 5

, provides a detailed evaluation of these potential FIV stresses and comparison with allowable values assuming that the collar weld is completely disengaged &om the shroud..

4. SPARGER INSTALLATION A key parameter in evaluating likelihood of the section of the piping. near the collar being adversely affected by flow induced forces during normal operation and post-LOCA operation is the potential clearance between the sparger T-box and the inside surface of the shroud.

GE-HE-Bl3-0l86932, Rn.l The Browns Ferry 3 Core Spray Spargers were manufactured and initially installed into the shroud by Rotterdam Drydock (RDM). The core spray spargers, which were purchased with the shroud, include the section of six inch pipe (annulus piping) which penetrates the shroud, the elbow, and the vertical section up to the coupling. After the shroud assembly was delivered to the site, but before it was installed into the reactor vessel, all the Browns Ferry 3 core spray spargers were removed, sent oQ'site for rework of nozzles, and reinstalled into the shroud. The extension piece and collar (items 11 and 10 on RDM drawing FOL-33402) were replaced as part of the reinstallation process.

The procedure governing sparger reinstallation (RDM NO. 10.30-3) required that the 4 inch pipe size 180 degree arc sparger half assembly be in contact with the inside wall of the shroud adjacent to the 7.087 inch diameter hole in the shroud when it was fit-up. During rewelding of the brackets (5 azimuth locations) which support each sparger half &om the shroud inside surface, four large C-clamps were used to hold the four inch pipe in contact with the inside of the shroud.

The reinstallation procedure specifies that the original drawing zero.gap (contact)'equirement at the bracket locations be met. Thus it is expected that there will be zero radial gap between the shroud inside wall and the 4 inch sparger pipe adjacent to the hole where the 6 inch pipe penetrates through the shroud. However, since the as-built data was not located to verify this zero gap, and because the RDM procedure acknowledges that a worst-on-worst (WOW) stack-up of shroud and sparger drawing tolerances would allow some radial gap, the WOW radial gap of 0.0625 inch was considered for the analysis.

The diametral clearance between the 7.087 inch diameter hole in the shroud and the 6.625 inch pipe outside diameter is 0.462 irich. There is a vertical support bracket, welded to the shroud only, directly below th'e 6 inch pipe, which would prevent the pipe &om moving downward.

There are five 0.38 inch thick brackets (welded to the shroud only), uniformly spaced along ea'ch 180'degree sparger half (approx. 180 degree arc) which prevent the 4 inch pipe &om moving up or down. Thus it is expected that the 4 inch pipe sparger with its lateral support &om the shroud wall, and its support brackets, would provide significant lateral and vertical support for the 6 inch sparger inlet pipe. However, it was conservatively assumed, for the FIV analysis, that the 6 inch pipe could move +0.23 inch (upward, downward, left or right) limited only by. the clearance in the hole.

GE Nackar &mgy GE-NE-Bl3-01869-032, Rcv. I

5. FIV EVALUATIONASSUMING COMPLETE DISENGAGEMENT OF THE COLLAR WELD Information provided in the preceding section indicates that ifthe collar weld is assumed to have completely detached (i.e., zero remaining ligament), the pipe in the shroud hole could move up to 0.0625 inches in the vessel radial direction. A similar review of the diametrical clearance at the shroud hole indicated that the pipe can also move+0.23 inches in the lateral directio'n.

Figure 5 shows the finite element model of the core spray piping system used for this analysis.

The three displacement load cases (0.0625 inch in the radial direction, 0.23 inch in the horizontal and vertical directions) were first run. The resulting moments Rom the three load cases were combined by the absolute sum method and the peak stress range. at each of the welds was calculated using the appropriate stress concentration factor. The stress concentration factor .

values used were 4.8 at the fillet (e.g., at the vertical slip joint) and 1.8 (2 used in analysis) at the groove welds. The maximum value of the calculated alternating. stress (one-half of the peak stress range) was 1910 psi. Obviously, this value is considerably less than the threshold value of 10000 psi (Reference 4). Based on this it is concluded that even ifthe collar weld is to detach and the core spray pipe were to move the magnitude permitted by the assumed clearances, FIV is not a concern.

A primary plus secondary stress evaluation showed that even when the FIV stresses are added to the other design base load case stresses, the largest stress range is still less than the allowable value of 3 S ~

P

.In addition, the impact on the allowable flaw size on the P9 weld was evaluated assuming the collar fully cracked. The results show that the allowable flaw size at weld P9 based on the uncracked collar configuration still bounds the calculated allowable value assuming the collar completely cracked, that is the stresses based on the release of the collar moment resistance are lower at the P9 weld.

6. EVALUATIONOF LEAKAGEIMPACT Because one function of the core spray collar is to prevent leakage from the inside of the shroud to the outside of the shrou'd via the core spray piping penetration, the impact of this potential leakage was evaluated. For the evaluation, it was conservatively assumed that the collar is complete detached &om the shroud and that it is separated by a maximum geometric allowance of

~ GE Nicker hoagy GE-AZ-Bl3N1869-032, Rev.l 1/16 inch. The evaluation shows that leakage &om the inside of the shroud is less than 0.02% of rated core Qow. This magnitude of leakage is smaller than that calculated for shroud horizontal cracks which has been evaluated as having an insignificant impact on both normal op'eration and safety evaluations (Reference 6). Therefore it is concluded that even with the bounding, assumption of collar disengagement &om the shroud, collar cracking does not have any safety impact on the BFN 3 plant.

7. EVALUATIONASSUMING INDICATIONSIN SHROUD 4

The nominal thickness of the shroud at this location is 2 inches. These indications are expected to be shallow (typically, less than 0.35 inch) based on field experience related to shroud cracks at sparger brackets. A bounding crack growth rate of Sx10'n/hr has been used in the shroud integrity evaluations. This rate implies a crack growth of 0.6 inch for 18-month cycle of operation (-12000 hrs). This would mean a predicted crack depth of less than one inch. Thus, if these indications are assumed to be in the shroud, they are not expected to grow through the shroud'wall during the next cycle of operation since the shroud wall is much thicker than 0.6".

Furthermore, even if it assumed that these indications become through-wall, the shroud Qaw tolerance at this location is well in excess of 100 inches.

Based on the preceding discussion it is concluded that shroud structural margins will be maintained ifthe indications are assumed on the shroud side.

8. IGSCC SUSCEPTIBILITY EVALUATIONOF CORE SPRAY WELDS Core Spray Piping Collar Weld PSb Cracking at the core spray collar location has been detected at a relatively high &equency in recent outages. With this finding at BF 3 there are now six incidences of cracking at this location.

It is important to distinguish between cracking that was detected visually in the heat affected zones of the collar itself &om cracking that has been detected by ultrasonic techniques that is believed to be in the shroud underneath the collar location. There are different factors that contribute to the IGSCC susceptibility of each.

The factors that are likely to contribute to IGSCC in the heat affected zone of the collar-to-shroud weld as compared to other locations in the core spray piping are: (1) the possible presence of a'revice geometry associated with the space between the collar and the OD of the

GENackar Zsngy GE-NE-BI3<l869432, Rcv. 1 piping, (2) the weld geometry itself, and (3) rework associated with sparger re-installation. These factors are discussed in more detail below.

The BWRVIP Core Spray 1&E Guidelines (Reference 1) describe the collar welds as crevice welds. However, the geometry of the region between the collar and the OD of the core spray piping suggests that this region (see Figure 1), while it may be a potential crevice, location, should not act as a severe crevice location. In'act, the crevice gap is 0.5" for a crevice length of >1" (approx. 2.4", Reference 73 18779). In contrast, the crevices at the slip joint location which have had a high &equency of significant cracking are approximately 0.03" and 0.02" for a crevice length of >1". The field data is consistent with the geometry. The two inspection events that detected indications in the collar welds by visual examination and have been confirmed by ultrasonic testing have shown that ID and OD lengths were comparable. This suggests equal probability of the cracking being OD or ID initiated thus further suggests that the environment on the ID and OD is likely to be similar. In addition, the collar cracking has been less than 180 degrees in length which is consistent with indications that have been detected in other core spray piping groove welds that contain no crevice. By comparison, the results of the inspection events at locations that are associated with a severe crevice show that cracking can be significant. One such area that contains a severe crevice is the slip joint location."

The cracking found by UT at the collar to shroud weld location'owever has been found to be fairly significant in size as compared to that found in the collar itself. It is important to note that this cracking has not been confirmed visually at these three plants (One plant, which did not-perform UT, located a 1.5" long visual indication on the shroud OD, at a location adjacent to the collar to shroud weld visible &om the shroud OD).

One of the contributors to increased susceptibility at this weld location is the weld geometry itself.

Although a full penetration weld was specified, full penetration would have been dificult to achieve (as compared with other groove welds in the core spray piping) because of the large heat sink associated with the shroud and therefore it is expected that there would have been potential dif6culty with drawing the root at the shroud location. It is likely that this weld would have root defects such as lack of fusion associated with it. In additio'n, because of the configuration, the root was not accessible after welding, so visual inspection of the root would not have been possible. Ifa weld defect such as lack of fusion occurred, it could create a tight'crevice near the heat affected zone of the shroud and contribute to increased susceptibility to IGSCC at this particular weld location.

GE Nectar Estray GE-NE-Bl3<1869432, Rev. I The collar to shroud. weld was originally fabricated by the shroud manufacturer but was removed and re-made in the field during sparger modification (shroud was not in the vessel during the sparger rework). During this modification process the collar was removed and the outside of the shroud was then ground prior to sparger reinstaHation. A new coHar was then rewelded to the shroud as part of the reinstallation of the sparger. It has been well established with recent shroud inspection findings that the presence of heavy surface cold work due to grinding can increase the ~

susceptibiHty to IGSCC.

In conclusion there are unique actors associated with the coHar-to-shroud weld such as the grinding imposed during the rework process and the difBculty of making the weld itself to suggest that these factors most likely would contribute to the increased susceptibility to IGSCC of this weld compared to other core spray piping welds. Based on this and field data, the environment at this location would not be expected to contribute to the increased susceptibility of the weld.

'I Evaluation of Inaccessible Weld P9 0

Although the BWRVIP Core Spray IAE Guidelines (Reference'1) refer to P9 as a crevice weld, it has very dUrerent characteristics than the P8b weld which was found to be cracked. Field data supports the conclusion that this region does not behave like a true severe crevice and therefore significant cracking would not be expected in this weld. The P9 weld is expected to have a susceptibility similar to other girth butt welds in the core spray piping which have been inspected either ultrasonicaHy or visuaHy this outage and show no indications, with the exception of the minor indications previously noted on weld P4d.. Several years ago at BFN 3, one visual indication was located at the header arm to nozzle T-box, but that location is also considered to have a high susceptibility'o IGSCC, as evidenced by the high incidence of cracking because of the instaHa'tion induced stresses.

Since the overall population of girth butt welds in BFN Unit 3 internal core spray piping do not show incidence of cracking, other than the previously noted P4d weld, there is a strong basis for concluding that the currently uninspectable weld P9 has not experienced significant IGSCC. Even ifsome amount of IGSCC has occurred in weld P9, the BFN 3 Core Spr'ay Line Flaw Evaluation Handbook, Reference 2, indicates that this location could tolerate an existing through wall crack of greater than 9.8 inches in length. This is based on results for the P4d weld which is proximate to weld P9, the fact that P9 is a non-Qux weld, and the fact that the allowable Qaw size will even be. larger than the allowable for the P4d weld. This is typic'al of. other girth butt welds in the system where the allowable crack sizes range &om 10.8 to 11.7 inches. With the collar weld

I GE Ãuckn'nergy GE-HE-BI3-0l869-032, Rev.l

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disengaged &om the shroud, (i.e. loss of moment restraint) the allowable flaw size at weld P9 will still be bounded by that calculated with the collar weld in tact. This is typical in a piping system near a moment restraint (i.e. an anchor). If the restraint is released, bending moments in the piping near the restraint actually decrease as the load redistributes through other load paths. In this vicinity, the reduced bending increases the flaw tolerance of weld P9 (i.e., increases the

,~

allowable flaw size).

9.

SUMMARY

& CONCLUSIONS Although the indications at the collar location are believed to be located in the shroud itself, for the purposes of conservatively evaluating the capability of the core spray piping for continued operation,' bounding assumption was made that the indications are located in the collar and that the collar is completely disengaged &om the shroud. Using this bounding assumption, an evaluation of the resultant stresses on the core spray piping was performed. In addition, a structural assessment was performed for the more likely condition where the indications are located in the shroud.

The results of this evaluation shows that even for the most limiting assumption of cracking in the collar and complete disengagement of the collar &om the shroud with movement of the core spray piping within clearances, the piping stress increases due to FIV.are minimal. Additionally, the leakage &om the collar is not a concern because (1) the core spray injection flow is not affected, (2) any leakage of core flow would be very small due to the tight tolerances between the piping and the core shroud at the penetration location. The natural &equency remains nearly unchanged withthe collar disengaged, thus eliminating FIV concerns. Furthermore the presence of the uncracked ligament will assure some axial load carrying capability which has not been accounted for in the evaluation. It has also been concluded that adequate structural margin is maintained for the more likely case that the indications are located in, the shroud.

In addition, it is concluded that the collar-to-shroud weld may have a greater susceptibility to IGSCC than other core spray piping welds because of the dif6culty of the weld orientation which may have resulted in an inherent root defect and thus a crevice geometry and the rework and grinding at the shroud location that was associated with core spray sparger removal and re-installation. Therefore, the inspection findings of this weld are not expected to be a good indicator of the susceptibility of other welds in this location such as the P9 girth butt weld. The susceptibility of this weld is expected to be similar to the other non-crevice groove welds in the 9

GE-HE-B1341869432, Rcv. 1 core spray piping for which no indications have been detected in this outage. Therefore it is concluded that weld P9 is capable of performing its intended function without veri6cation of its integrity by examination.

In summary, the results of this evaluation that this weld is not a true crevice weld, the favorable inspection results from similar welds, and the large flaw tolerance of weld P9, support the conclusion that no inspection of weld P9 is necessary.

The core spray piping structural analysis has been performed to demonstrate that even with a completely'disengaged P8b weld at the shroud/collar interface, the maximum stresses in the piping during normal operation and design basis accidents will remain within the ASME Code Section III allowable stress limits. In addition, the minor indications noted at weld P4d are well within the allowable fiaw tolerances.

10

GE 1Vackar Eengy GE-NE-BI3-01869-032, Rev. 1

10. REFERENCES "BWR Core Spray Internals Inspection and Flaw Evaluation Guidelines,"

BWRVIP Report No. EPRI TR-106740, dated July 1996.

f21 "Internal Core Spray Line Flaw Evaluation Handbook for Brown's Ferry Units 2 and 3," GE Report No. GE-NE-523-B13-01805-22, Rev. 1, January 1997.

73 1E779, Core Spray Sparger.

GE Document 409HA105 Revision 1, "Fatigue Design Criteria", BWR Materials and Processes Handbook, January 1975.

t:5l "Preliminary Design Handbook for Flow-Induced Vibration of Light Water

, Reactors", GE Report No. GEAP-24158, November 1976.

[61 "BWR Shroud Cracking Generic Safety Assessment", GENE-523-A107P-0794 Revision 1, dated August 1994.

GE SIL 289 Revision 1 Supplement 2, Cracking in Core Spray Piping dated January 1996.

GE Nuciear Energy GE-NE-Bl3-01869-032, Rev. 1 Table 1 Indication Geometry and Ligament Calculation Indication Indication Indication Indication Length As-Found Ligament No. Start (') Finish (') Length (') (in.) Ligament Length Length (in) AAer One C cle in.

30 30 2.1 0.6 .

38 44 0.4 3.7 2.5.

97 318 221 15.4 1.0 0.0 333 360 27 1.9 Note (1): Based on a crack growth rate of 5.0x10',in/hr. For 18 month fuel cycle (approx.

12000 hours of hot operation), this crack growth rate is equivalent to a growth of 0.6 inch at each end of an indication or a reduction of 1.2 inch in the ligament between the two indications.

Table 2 Anchor Displacements for Various Operating Conditions

/

'emperatures Operat. Cond./ ('F) RPV Press. Displacements Pipe Temp Transient (psi) (in. ('F)

RPV - Shroud Stilts Horz. Vert 522 522 522 1000 0.502 0.065 522

'LFWP 300 400

'5 665 0.270 0.143 300

'5 100 LOCA1 '522, 534 522 - 0.407 0.065 201 LOCA2 522 281 281 0.407 0.732 201 The temperatures and pressures stated in the above table are derived from the information provided in the Browns Ferry Thermal Cycle Drawing 729E762.

11

GE nuclear Energy GE-ÃE-BI3-01869-032, Rev. 1 PSa Psb COILAR SHROUD

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P9 T-BOX COVER PLATE Figure 2 BFN 3 Core Spray Sparger T box Assembly 13

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GE Nuclear Energy TVA Browne Ferry Nuclear U3C7 Core Spray UT Project 1GVQF S pring 1997 Core Spray "C" Downcomer - Weld PSB Indication Dafa Total Scan Length Examined (Deg.) Thickness (In.) 0.16" 360.00'5.13" Total Scan Length Examined (In.) CircUmference (In.) 25.13 Percentage of Weld Length Examined 100.00% Inches per Degree 0.07 Percentage Flawed of Examined Weld Length 78.89% Degrees per Inch '4.32 Percentage Flawed of Total Weld Length 78.89% Pipe Diameter (In.) 8,00" Total Flawed Length (Deq,)

284.00'9.83" Total Flawed Length (In.)

Ind Start Trafls. ~

No. (Deg.) (Deg.) (Deg.) (In.) Used 1 30.00' 2.09" 60 and 70 2 30.00'.00'21.00'7.00'ength 0.42" 60 and 70 44.00'18.00'60.00'ength 0.00'8.00'7.00'33.00'top 3 15.43" . 60 and 70 4 1.88" 60 and 70 Indication Comments:

Indications are located on the shroud pide of the component.

Indications 1 and 4 are one continuous indication.

Prepared By: Date 8 0 'Reviewed By: Date 7

0 CORE SPRAY C'OWNCOMER WELD P8B INDICATION DATA 0'18'33'0'8'4.'70 9T 90'8.00 6" SCH. 40 PlPE COLLAR 1

80'R SKETCH RELEASE PAR PR iRM

Figurc 3 Rcportablc Indications at Collar Q'cld (C;ont'0) 15

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I I ULTRASONIC SCAN DATA PRINT SHEET GE Nuclear Energy (AUTOMATEDWITH Smart 2000)

Q p8b1:C P 78DL 884-1: P Qgg 5.88 186.42 deg 8.888 1/2 9.198 in Hal f Path QOcp8b1:C~ P< 78DR886-2: Q~

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GF. boucle((r &(ergy GE-NE-8 I3-01869-03?, Rev. I e Effect of Conductivity on Sensitized 304 Crack Growth Rate Crack Grovrth Rate, in/h 1.000E-04 200 mV.

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+ rA4W "P:,:;~ "m'~'.",.

~ .

S, l ;c~-

'tl,

~ ~

r (Vai~ 7+4, + 7C

. 2 iu)is~P~~.~

D/g + k~)

6<~1

~ ~ c.~ ~m~~~ [<<'

Appendix A Core Spray Sparger i~1odit>cation Drawings

erlaeiC-C L l-"-

RO 5 OC:C C YA Pi hCCS t-i 1 2.

~ i~M TYPAL AIClOIVIN AAJI

~ Nar ~C<~

SRACKCY'TO I--'SPARSCR I

I I

aA' I

s f <<'IA I

I l.

I a~

I III' aar

~n I

I I

0

Appendix 8 Weld Procedures

0 TENiU "M~i VALLI'Y AUTltQijtTY Oc:.>>il Weld Procedure No.: GT88-0-1 Ray.: 0 Date: 5/14/70

~~

75~

PQ WELD JOINT DESIGN Welding Conditions; Layer No.

Current 60-l20 amps Polarity DCSP Arc Voltage I

X2 vcltrt Travel Speed Flectrode Type Eath-2 Electrode Size 3/32 li '~@

Fil!or Mc:ol Type Za-308 ..

Filer Vota>> Size 1/3<5",oi 3/32" Flux Type Flux P:rticle Size I ~

Sllicldin." Gas Mgctt "

Shielding Gas Flow r ate 85 cfh Ouriiil'" Ge< ~ Argon .

Pu:g ni; Gas Ftow Rate g-7 cK Gas'Cup S xe 3/8 ll Gas Cup Tc Work Distance 1/2" max ~

s I

Pfr.uiut 60o F min I idIfPlW i mP

~ ~

'3$ 0c P max I P- ~ l Plaid Hear Treatment , ~

8:! ding Position T~ H~ V~ OH r ~

I Qtti:r I

~ ~

i ~

R"lerancc documents:,P.S. 3..M.l.X(b), QZ88-0-,$

ni ~,'i roved uy

6

%m)lag 8,~ 9 .

~ ~

Q g g+gI%+IIA'AA'L'IIL%l akth> i ~

' ~ ~

I I ~ I ~: ~ I . I I ' '

r

]0 0

~~EB VhLLRf NiOBXK 3 'EB)C';:))VCIZAA~PLAJ)T"::;~":. U))I'2 Ov,g nv n aiirw)c).),'rzcams-"': COW.',IHflEX'.))0.'

'~"'...b" I~

fO)< PmJSU)Z "VZS<~u '

ipiC'"))'el'-

f

\

R)' Oe'c

~

f Mcldmcnt Ident'LfictLt,lan 47~4M Comyonantf: T To ~A'T ~

Ac Ses7 5 C C ~M6rR.

CE 1)@tee hoe 7~/a~9 I

5 Mc3.ding )') occdurc

(ig);i.. Qupplamant.a!. ))n4< G)feat BC<t'de by CI; Bpaa. 25?N3,>Oh)) lt2 ~ Xee lln " e

).'Xgm."'.,

fl WcMer IdantifictLtion m,ien i.e tel xeentfxfeeetnn, 1, c Inn actor

'I t~an5.a 'n">~

'(4~,lj",i'j,'f'Iegen

-lS P 'wm Wclhinp .",Bccif)cation t;onfon" nca oA '...'"!.'95 I

Boot; <</S-2 5 -:Wl

  • ~

bi" .'.f

Pf T. 1 'ull Innp. ,Q gm)

P. 1"f>ll

, If~

~

Canal oto r/7- 7$

Viaunl Knape t)T Tnn

'+it'

~Ba air ) )mention Sc All'oquircd inapcat;iona Morc pcrfvnaah Ittaptr. P Sate It il5 5

>f ) to I.nl T5 anti t') cn n 5tc I(

. ~

~ 'y

'E)f)IFSSEI" VAIL'Y;:.'hUT)IOIUTY '.:

3)BOW))8'FED)lYyNUCL1A)I'P).hl)T.'IQT'l(0~';

qVhr,m ASmrthuC)',.:~u.CO)IL)

))IPCTO I I sty) U)I)h,,~PU) ) r~

Xi)nim HO.

~'u""'".

w

. >> .'i:

e

~ g

~ $

,'-'-'.""'
39 y'i P I I h

~ >>.

+ ~

MclAwnt Id~-'nti5'ication 47C430 'i/

ii Component,n /T / .'Pe.

~

Vo ~r ~

4ec7 C>>< 'P~4ae ~ <<t'

<<<<y GE DMC. ho, ZW5 i/

1/.i, i'i;h

,I Mc3.ding I'ro"cdur 4 ' I

.g'/<<

Qupplcvcntz.t Data Shoot Hcq'd. by G)."Qpccy 0"A2150A)) P2. Xec

~:,

A; Molder Xdcntii'ication

'k': ~

Filler Vc tel lccnti )'icr,tk on l)ntc Znnncctor Canmento Fitu Inn action -9'-79 L)cldinp "peoit5cation Conf'oncanon //. W9 I y *, p )toot ) +0 y/il >>p hh P

.-,.jpig~

Pe Te ) ~ )'n)1 A. "c >

Xnspi

+iiA ~ 23 &11 l4'to oat

h>> '

Cowplcta -//. V3 Viutwl annoy. -]/>>/73 U Tngn ~

~l

~

hW. -S

'g%'y,

~Or. air 1 Inaction Type

~

i

'V/r>>ii/ ~

/V+

-A'".

Al,l rci)ui)vd knopcel.iona vore pcrformcd Xncptr. bate

~

>> I

),. ~

..a

. c.$ @.

y,'

yhi P511cr h!ctcl Ident]ticnt on iAi>>.<<>t ".

4 l

o 8

)C~ I I.'EllllFSS1N, YAlk AUI'llOAITYX.fc) fJAOVl13 HlAAX NJClZNR 'KAAi ""'"'Uh UllIT.NOo,,

J.ITX MQUAAMCB ill'ICOA)4" HlNCTOA PBPlSUlS Yl~SHIf C+U< XlfDEXhO

'IZC'lt'O.".::

i I

~"'~'o ti Moldmont Xdf:nt;ification 4'7~4i~O +i A Coag)anent o /~ ll ~~

$ wc7 C H c.'p i 'C "SP~A'6'aC ..

GH DMG, ho, Molding Proaodur~+

Suyplcinontt..!. Dut~ Uhoct; Hocl'd. by GE Gpoo. f".2A8150AD H2.

Molder Xdcntiflcation Filler letnl. Xdontificr tion 1

Inftvnctar Cmaaonto

~f'fL!Ir Tiia IcLTIII Cg~/f )Q lffclclinu !Iaooif$ cation Ccnfo~noo g-/$ -7)

Hoot 1'nopf

~l Pall P. 'ftll Caafnlctc 4 /'7-7>

Vianttl Xn"lf.

UT Tan

)b>>air 1 )ment.ion All roquircct inopoctiono Morc parformad In"pt,r. Stttc,. P Ftllcr Matfll TR~ t.ti'nt)on

~ I ~4@Mw ".""

Q 0

'gal)P SN."VAMP':"AgniJOJJI'K:

tJJJIT"",lloyd'"

')))0)J) 13 >'+~'. I)IJClZAB 'lCAllT" QfhTiJ>< <~>JUllJN; AgCO)116 Ce~~ iowan IJO,"',=.

)L'ACTO)< Pl&GVlg V)".JJUJ 01VJ': NO':"

n

,~T Q

9'l

~ <<'J 11 F

Xdcnti)'iaatgon fo -8 Jr>> C~>>

f> 4'7~4'am])onunt,t:

. Vo J'a1dmant Sac, aP'~"4/P/Perh G)J JVpa Jln.

)laldf ng Proachur< QT ~ ~

~i >.

'1

. Gupplaman&L Data Shai.t )1cq'd. by 0)J Qyec. MA21>OA))

IWJI J ~

Oft Mal.dar Nant%i'icatiou I"L13.ar Matal Xdantiifaation 4 cs gfa

~ l.<<

IILna Innnnnnan Qxmanta Fi ta~Inr. an.nina r /JK" 7 1!cMinp Opacity f atf on c Confornnnca s-lB-~>

'oot -/0 7')

Pe To XnOP1

~13 A>11

? " 9>)l Coai~loto f~/ 75 Y ioua1, Zna)I.

O'2 Tns 1

~)4. air 3 Jmantion

+pl J

A11 raqui)wd inqpaationn Mara pari'orma4 Xnsptr. f+ I)ata

~a)dor Tdan);J fiant)on

)'illa ~ )ict>>3, Tdi it] i'(riot

GE unclear Ener~ GE-XE-Bl3.0l869-032, Rev.l Appendix C "Internal Core Spray Line Flaw Evaluation Handbook for Brown's Ferry Units 2 and 3,"

GE Report No. GE-NE-523-B13-01805-22, Rev. 1, January 1997.