ML092440518

TVA Conference Call Presentation Slides on Browns Ferry Nuclear Plant, Unit 1 Steam Dryer Analysis

ML092440518
Person / Time
Site:	Browns Ferry
Issue date:	08/07/2009
From:	Tennessee Valley Authority
To:	Office of Nuclear Reactor Regulation
Brown E, NRR/DORL, 415-2315
Shared Package
ML092440524	List: ML092430520 ML092440518
References
TAC MD5262
Download: ML092440518 (14)

Text

lim TENNESSEE VALLEY AUTHORITY BROWNS FERRY NUCLEAR PLANT UNIT 1 Steam Dryer Analysis August 7,2009

Steam Dryer Stress Analysis [II]

• Low Flow Noise Included

• Re-analyzing Steam Dryer Stress to Show SR > 2.0

- As built steam dryer at 110 % OLTP

- Modified steam dryer at 1200/0 OLTP 2

Steam Dryer Stress Analysis [II]

• 1100/0 OLTP Based on CDI 08-15P (March 2009) with:

- Low flow noise included

- Adjusted bump-up for 1100/0 v 2 & 110 % resonance

- Same steam dryer configuration

- Utilization of ASME Table NG 3352-1

- SR > 2.0 3

Steam Dryer Stress Analysis iii]

• 120% OLTP Based on COl 08-15P (March 2009) with:

- Low flow noise included

- Additional steam dryer modifications

- Revision of two submodels o 1 SIA - 1 COl

- Utilization of ASME Table NG 3352-1

- SR > 2.0 4

Steam Dryer Stress Analysis [II]

z x~ y Outer Hood - Old Bar

& Lock Gussets Group I Drain Channels Group III index I Inner Hood Stiffeners Group II 5

Steam Dryer Stress Analysis mil Middle Hood/F&T Tie Bar Group IV Outer Hood Side Panel I Vane Bank End Wall Group V Outer Bank Discharge End panel I Middle Hood I Top Cover Group VI 6

Steam Dryer Stress Analysis III]

Noise Retained Modifications Reinforcing Bar ole Old Tie Bar/Lock Gusset Replace with TVA Gusset Group I lli; i

't:! *  ; ll~

-.L 3tL Drill Yo" DIA Re' ThtuP lie

~ Two (2) lJUssets are "'ll\lired per C-vssel Pad s:eam dam. four (-4) iotal per unit.

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~Oam(1

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Existing Configuration at 4 Locations, Where Old TB Remnant and Lock Gusset Were Retained.

Stress Intensities Seen in Base Plate, TB Connection & Lock Gusset Connections. 1 Mod Removes this Configuration and Replaces with Revised Gusset as Found in all other Locations, Stiffens the top of Steam Dam with a ~

Pipe Section, & Reinforces the %" Thick Outer STEAM DAM GUSSET ASSEMBLY Hood Cover. PATCH PLATE LOCATIONS DETAILS - BFN U1 7

Steam Dryer Stress Analysis 1m Noise Retained Modifications Inner Hood Stiffeners - Group II 3.f1E Limiting stress location is at bottom corner of 3,1 Hood Stiffener 2 sided fillet weld. Addition of stress relief semi-circular hole reduces stress acting on weld and adds flexibility to corner. HOOD SlIPPORT Modifications provide a resultant SRF = .53

.2:5

---

~1.75 I

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Previous Solid Sub Model Revised to Evaluate Stress Relief 000-TO-HOOD SUPPORT RELIEF HO ASEUNE DIMENSIONS and Resultant SRF 8

Steam Dryer Stress Analysis [iI]

Noise Retained Modifications 1Ia" Drain el(ref}j J'ttt Drain Channels - Group III R 3.50 (lefl - \

DC Follow the Dryer Skirt Modal Response. Limiting Stress Location is at ~A Bottom of Drain Channel Weld, that has been Already Reinforced and Wrapped Underneath the DC. Addition of Stress Relief Semi-circular Hole Reduces Stress Acting on Weld and Adds Flexibility to ----114" Dryer Skirt (reI) _ _

Corner.

Modifications Provide SRF = .43 18" [)fain Ch01f1nel (reI) -_~/ _

Previous Solid Sub Semi-circu Re~H Model Revised to 'Nolie: These dimensi:>ns are g;ven as arc I~

Evaluate Stress Relief along .!he O'..I"V3".ure of drain Ch01f1 Section A-A and Resultant SRF DRAIN CHANNEL END RELIEF HOLE CONCEPT 9

Steam Dryer Stress Analysis [iJJ Noise Retained Modifications 6 This n:et::h is appbcable only co lie bars spanning the ou~r ci;scharge duc.-:s. 4 reauired.

.... - -- - See FW'e Middle Hood/F&T Tie Bar - Group IV One location, between outer and middle banks, has a high stress located under the tie See OU.:er Tie Bar-to-Hood bar in the weld to the hood section. Additional "

Reinroreement DetI:iI Shee, reinforcement using a reinforcing plate and additional welds is to be added.

Vane Rank A total of four (4) symmetrical locations will be Cover (rei) 8,80t:om comers ma~ be rounded to 0.25" maximum rallYs

'thin % 1 inc:ll 01 flare break line to {aciSta:e welding.

modified.

l~ ~ 1**1 l'

'j ,I. 6" *1

~, [7/0-Max (ref) C ,__ .. __.-- .-~

Surfac.e may be m.a.chined a requ'red ior lihlp if vane bank FLARED & TAPERED TIE BAR to hood offsl!l is Iessthill 114'_

OUTER VANE BANK DISCHARGES 10

Steam Dryer Stress Analysis mil 318" x 2" Reinfordng Bar Noise Retained Modifications "7 3/8" Vane Bank 3/8" Outer Hood ~. L-- End Plate (ref)

Closure Plate (ref)

Outer Hood Side Panel Bf

/ Vane Bank End Wall 1/4" Vane Bank Outlet Group V Upper Ring (ref) C Skle Trough Plate (ref) 1/2" x 6-1/2' Trough ReinforCing Plate, Both SiOes (re.f) 1/2" Vane Bank Bottom Plate (ref)

Limiting Component is the 3/8" thick End View - Outer Hood Closure-to-Vane Vane Bank End Closure Plate.

1/2" x 6-1/2' Structural Thickness Changes Of Trough Reinforcing Plate (ref) ~ 318" Vane Bank End Plate (ref) -

Drain Trough, behind Plate, Contribute to Stress Intensity. Mod Provides 316 Reinforcement to Distribute Stress

~~ ,

2' x 318" thk x 24" Ig Reinfordng Bar 318" Hood Closure Plate (ref) - - ' ..., I lY Section A-A (Cut Thru Trough) Section B-B (Cut Thru Perforated Plate) 11

Steam Dryer Stress Analysis [II]

'A~

R 0.25 (TVP)

Noise Retained Modifications +

Outer Bank Discharge End panel

/Middle Hood/ Top Cover 114 Group VI Limiting stress is in the 1f4" thick hood cover plate and 1f4" attachment fillet weld. Mod provides additional reinforcement, additional 3.00 weldment, and stiffening.

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-L- ~ ,_,~-

"_ ..LJ B

~

MIDDLE HOOD/COVER PLATE/END CLOSURE REINFORCING GUSSET 0.25 0.75 SECTION B-B 12

Steam Dryer Stress Analysis [II]

- Interim Operation at Limited Power o Based on stress analysis at 11 Oo~ OLTP with currently modified steam dryer o Low flow noise included o SR > 2.0 o Implement mid-cycle

- Operation at 120% OLTP after Additional Steam Dryer Modifications o Based on stress analysis at 1200~ OLTP with additional modifications to steam dryer o Low flow noise included o SR > 2.0 o Implement modifications Fall 2010 13

Steam Dryer Stress Analysis [II]

Planned Submittals

- 110 % OLTP o Load report o Stress report o Limit curves

- 120% OLTP o Load report o Stress report o Limit curves o Submodels

- Submittal by August 28 14