ML20066H808

Forwards Results of Steam Generator Tubing in-service Insp Completed in 900427.No Commitments Contained in Submittal

ML20066H808
Person / Time
Site:	Sequoyah
Issue date:	02/19/1991
From:	Wallace E TENNESSEE VALLEY AUTHORITY
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 9102210345
Download: ML20066H808 (20)

Text

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Tewssee vaney Auwe noi uaw sees cnanawga lewsm vc FEB 191991 U.S. Nuclear Regulatory Commission ATTN:

Document Control Desk Washington, D.C.

20555 Gentlemen:

In the Matter of

)

Docket No. 50-327 Tennessee Valley Authority

)

SEQUOYAH NUCLEAR PLANT (SQN) - UNIT 1 - STEAM GENERATOR (S/G) TUBING IN-SERVICE INSPECTION In accordance with the requirements of SQN Unit 1 Technical Specifications, paragraph 4.4.5.5, enclosed are the results of the S/G tube in-service inspection completed April 27, 1990.

An in-service inspection was performed on 204 tubes in each of S/Gs 2 and 3.

The in-service inspection result (defined in Technical Specification 4.4.5) was C-1 category for S/G 3.

The initial in-service inspection result of S/G 2 was C-2 category (because one tube was found with outside diameter (OD) corrosion greater than 40 percent wall loss); therefore, an additional 408 tubes (as required by Technical Epecification Table 4.4-2) were inspected. The second sample inspection result was C-1 category.

As a result of the in-service inspection, one tube in S/G 2 was plugged.

Independent of the in-service inspection TVA performed additional self-imposed, eddy current examinations such that a greater than 38 percent total sample was examined full-length by bobbin coil in S/Gs 1, 2, and 3.

Also, approximately 200 tubes were examined by rotating pancake coil (RPC) at both the hot leg top of the tubesheet and at the first hot leg tube support plate in S/Gs 1, 2, and 3.

A sample of row 2 U-bends was examined by RPC in S/Gs 1, 2, and 3.

S/G 4 had an approximate 10 percent sample examined full-length by bobbin coil and an initial sample of 50 tubes examined by RPC at the hot leg top of the tubesheet. The RPC examination in S/G 4 identified a defect in the top of the tubesheet expansion transition of one tube and resulted in an increased sample size to 21 percent total.

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'2 U.S. Nuclear Regulatory Commission

(( } g g}gj As a result of the self-imposed examinations, two tubes were plugged because of primary water stress corrosion cracking at the hot leg top of the tubeiheet (one tube in S/G 1 and one tube in S/G 4), one tube was preventively plugged because of OD corrosion at the hot leg top of the tubesheet (in S/G 3), and one tube preventively plugged because of antivibration bar wear (in S/G 3). No commitments are contained in this submittal. Please direct questions concerning this issue to J. D. Smith at (615) 843-6672. Very truly yours. TENNESSEE VALLEY AUTHORITY C <- E. G. Wallace, Manager Nuclear Licensing and Regulatory Affairs Enclosure cc (Enclosure): Ms. S. C. Black, Deputy Director Project Directorate II-4 U.S. Nuclear Regulatory Commission One White Flint, North 11555 Rockville Pike Rockville, Maryland 20852 Mr. J. N. Donohew Project Manager U.S. Nuclear Regulatory Commission One White Flint, North 11555 Rockville Pike Rockville, Maryland 20852 NRC Resident Inspector Sequoyah Nuclear Plant 2600 Igou Ferry Road Soddy Daisy, Tennessee 37379 Mr. B. A. Wilson, Project Chief U.S. Nuclear Regulatory Commission Region II 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323 i

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-4 4 1 1 4 1 ENCLOSURE i .,) 15 l J - I 4 SEQUOYAH NUCLEAR PLANT UNIT 1 t 4 CYCLE 4 INSPECTION t APRIL 1990 = STEAM GENERATOR TUBING INSPECTION RESULTS 5 lj e 2 .. ~

i e x Ji, SEQUOYAH NUCLEAR PLANT UNIT 1 s CYCLE 4 INSPECTION 16 APRIL 1990 // STEAM GENERATOR (S/G) TUBING INSPECTION RESULTS 4 o Table 1 Inspection Summary Table 2 - S/G 1 Inspection Summary . Table 3 S/G 2 Inspection Summary Table.4 S/G 3 Inspection Summary Table 5. - S/G 4 Inspection Summary = Table 6 Indications Table 7' Plugged Tube Summary =- -Table 8 - Homenclature .i G I

7 ^ 'IABLE 1 SEQUOYAH NUCLEAR PLANT UNIT 1 CYCLE 4 INSPECTION APRIL 1990 INSPECTION

SUMMARY

S/G 1 S/G 2 S/G.3 S/G 4 Total tubes examined 1857 2340 1688 1291 Tubes recording defects, 1 1 0 1(1) (140% wall loss). Tubes recording degradations S 48 8 9 (120% to <40% wall loss) Tubes recording imperfections 8 19 7(2) 11(3) _(<20% wall loss). )~ Notess' 1. ' Non-quantifiable van loss conservatively assumed 140%.

2. Two tubes recording imperfections also recorded degradations.

3. One tube recording an imperfection also recorded a degradation.

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I TABLE 2 e SEQUOYAH NUCLEAR PLANT UNIT 1 CYCLE 4 INSPECTION APRIL 1990 S/G 1 INSPECTI,Q1LStMMARY a ISI E LE HU}iDER OF TUBES No ISI Sample Tubes this Steam Generator 0 L NON-ISI SAMPLE General defect exams [ EXTENT (PRODE TYPE)] Full Length (bobbin col 2) - tube end to tube end 1315 H07-HTE (bobbin coll) - hot leg 179 H01-HTE (bobbin. coll) partial hot leg 203 Specialty exams-[ EXTENT (PROBE TTPE)) $2 ' Hot Top of Tubesheet (RPC) 200 Support Plate Intersection (RPC). 201 U-bend-(RPC) 13 TQTAL' NUMBER OF TUBES EXAMIF),p 1857 INDICATIONS - ISI SAMPLS No ISI sample tubes this steen generator 0 INDICATIONS - NON-ISI SAMPLE Tubes recording defects 1 (140% wall loss) Tubes-recording degradations 5 ~(120% and <40% wall loss) Tubes rancording imperfections 8 (<20% wall;1oss)

I TABLE 3 SEQUOYAH NUCLEAR PLANT UNIT 1 CYCLE 4 INSPECTION APRIL 1990 I S/G 2 INSPECTION SU) MARY ) si 1 ISI SAMPLF NUMBER OF TUBES FIRST SAMPLE I l General lefect exams-[ EXTENT (PROBE TYPE)] l Full Length (bobbin coll) - tube end to tube end 204 Specialty exams (EXTENT (PROBE TYPE)) Hot Top of Tubsheot= (RPC) 3 Support Plate Intersections (RPC) 2 U-bend (RPC) 2 ) Total tubes examined first sample 204 The first ISI sample was classified as C-2 Category, therefore an additional i sample was examined. SECOFD SAMPLE General defect exams (EXTENT (PROBE TYPE)] ~ Full Length (bobbin coll) - tube end to tube end 408 . Specialty exams (EXTENT (PROBE TYPE)) Hot Top of_Tubesheet (RPC) 1 Total tubes examined second sample 408 The second ISI sample was classified as C-l' category. l'. t a

TABLE 3 (Continued) e SEQUOYAH NUCLEAR PLANT UNIT 1 CYCLE 4 INSPECTION APRIL 1990 S/G 2 INSPECTION

SUMMARY

3 (Continued) NON-ISI SNMPLE EUMBER OF TUBIS ~ General defect exams [ EXTENT'(PROBE TYPE)] Full Length (bobbin coll) - tube end to tube end 709 H07-HTE (bobbin coll) - hot leg 176 H02-HTE-(bobbin coil) - partial hot leg 1 H01-HTE (bobbin coil) - pertial hot leg 697 C07-CTE (bobbin coll) - cold leg 86 Specialty exams [ EXTENT (PROBE TYPE)) 1-Hot Top of Tubesheet (RPO) 221 3 . Support Plate Interanction (2PC) 191 .U-bend (RPC) 50 TOTAL NUMBER OF TUBES EXAMINED 2340 \\

'a TABLE 3 (Continued) SEQUOYAH NUCLEAR PLANT UNIT 1 CYCLE 4 INSPECTION APRIL 1990 i S/G 2 INSPECTION

SUMMARY

(Continued) g INDICATIONS - ISI SAMPLE NUMBER OF TUBES FIRST SAMPLE 4 Tubes recording defects 1 (140% wall loss) Tubes recording degradations 4 (120% and <40% wall loss) s Tubes recording imperfections 3 (<20% wall loss) 'SECOND SAMPLE Tubes recording defects O p (140% wall loss) Tubes recording degradations 6 '(120% and.<40% wall loss) Tubes recording imperfections 10 .(<20% wall loss) INDICATIONS - NON-ISI SAMPLE 4 Tubes. recording defects 0 (140% wall loss) Tubes recording degradations 38 (120% and <40% wall loss) Tubes recording imperfections 6 (<20% wall loss)

TABLE 4 SEQUOYAH NUCLEAR PLANT UNIT 1 CYCLE 4 INSPECTION APRIL 1990 S/G 3 INSPECTION

SUMMARY

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ISI SAMPLE IMiSER OF TRBfd General defect exams [ EXTENT (PROBE rYPE)] Full Length (bobbin coil) - tube end to tube end 204 Specialty exams (EXTENT (PROBE TYPE)) Hot Top of Tubesheet (RPC) 1 Support Plate Intersection (RPC) 1 Total tubes examined ISI sample 204 The ISI Sample was classified as C-1 Category 'l NON-ISI SAMPLE General defect exams (EXTENT (PROBE TYPE)] Full Length (bobbin coll) - tube end to tube end 1139 C07-CTE (bobbin coll) - cold leg 164 H07-HTE (bobbin coll) - hot leg 154 Specialty exams [EKIENT (PROBE TYPE)] j ~ Top of Tubesheet (RPC) 189 Support Plate Intersection (RPC) 191 .U-bend (RPC) 42 TOTAL NUMBER OF TUBES EXAMINED 1688

TABLE 4 (Continued) SEQUOYAH NUCLEAR PLANT UNIT 1 CYCLE 4 INSPECTION APRIL 1990 Sf_9 3 INSPECTION SUMMAPI (Continued) INDICATIONS - ISI SAMPLE NUMBER OF TUDEji Tubes recording defects 0 (140% wall loss) Tubes recording degradations 2 (120% and <40% wall loss) ~ Tubes recording imperfections 4(1) ( <20% vall loss) INDICATIOITS - NON-ISI SAMPLE Tubes recording defects O g -(140% wall loss) Tubes recording degradations 6 (120% and <40% wall loss) Tubes recording imperfections 3(1) (<20% wall loss) Note

1. One tube recording an imperfection also recorded a degradation

I 'o TABLE 5 SEQUOYUI NUCLEAR PLANT UNIT 1 CYCLE 4 INSPECTION APRIL 1990 ELG 4 INSPECTION

SUMMARY

ISI SAMPLE NUMBER OF TUBES uNo ISI Sample Tubes this Steam Generator 0 NON-ISI SAMPLE General defect exams (EXTENT (PRODE TYPE)) 4 Full Length (bobbin coll) 326 H07-HTE (bobbin coll) - hot leg 162 C07-CTE'(bobbin coll):- cold leg 75 H03-HTE (bobbin coll) - partial hot leg 1 E02-HTE (bobbin coll) - (artial hot leg 223 H01-HTE (bobbin coll) - partial hot log 93 Specialty exams [ EXTENT (PROBE TYPE)] Hot Top of tubesheet (RPC) 728 l l ' Support Plate Intersection (RPC) 50 U-band (RPC) 0 y TOTAL NUMBER OF TUBES EXAMIFED 1291 INDICATIONS - ISI SAMPLE No ISI sample tubes this steam generator 0 I1TDICATIONS - NON-ISI SAMPLE i i -Tubes recording defects 1(1) (140% wall loss) Tubes recording degradation 9 (120% and <40% wall loss) Tubes recording imperfections 11(2) (<20% wall loss) Notest-1. Non-quantifiable wall loss conservatively assumed 140%.

2. One tube recording an irnperfection also recorded a degradation.

. TABLE 6 SEQUOYAH NUCLEAR PLANT UNIT 1 CYCLE 4 INSPECTION APRIL 1990 INDICATIONS S/G 1 E2w C21 Location ' Wall Lost Characterization Resolution (%) Non-ISI Samole 1 1 HTS + 17.5 16 TLBD wear Note 1 1 90 HTS + 17.7 23 TLBD wear Note 1 1 92 HTS + 17.7 11 TLBD wear Note 1 1 94 HTS 4 17.7 12 TLBD wear Note 1 2 44 H02 + 3.2 9 Manufacturing burnish Note 1 9 69 H01 + 32.7 21 Manufacturing burnish Note 1 11 56 H01 + 14.8 16 Manufacturing burnish Note 1 16 71 HTS + 1.8 38 OD corrosion Note 2 20 69 HTS - 0.5 97 Axial ID indication Tube plugged 22 7: CTS + 46.9 28 Manufacturing burnish Note 1 27 39 HTS + 21.5 29 Manufacturing burnish Note 1 '28 46-AV2 + 0.0 9 AVB wear Note 1 28 '46 AV3 + 0.0 14 AVB wear Note 1 ) 42-56 CTS +133.4 17 Manufacturing burnish Note 1 44 33-HTS'+ 2.0 6 OD corrosion Note 2 Notess' 1. Reexamine in future outages 2. Reexamine in future outages with a specialty exam Tube Lane Blocking Device (TLBD) Anti-Vibration Bar (AVB) t

( 'o TABLE 6 (Continued) s SEQUOYAH NUCLEAR PLANT UNIT 1 CYCLE 4 INSP3CTION APRIL 1990 INDICATIONS S/G 2 i ,1 Rax - Cn1 Location Wall loss Characterization BR. solution (%) First ISI Samole 4 2 55 CTS + 29.3 27 Manufacturing burnish Note 1 11 10 _H01 + 7.2 11 Manufacturing burnish Note 1 11 10 H01 + 24.4 8 Manufacturing burnish Note 1 11 10 H03 + 3.0 11 Manu*acturing burnish Note 1 16 36 HTS + 1.0 44 OD cerrosion Tube plugged 16 46 H02 + 38.5 8 Manufacturing burnish Note 1 17-26 CTS + 40.5 17 Manufacturing burnish -Note 1 ~18 .46 HTS + 0.8 26 OD cerrosion Note 2 19 12 H01 + 6.4-22 Manufacturing burnish' Note 1 35 27 HTS + 0.8 23 OD corrosion Note 2 35 27. HTS + 16.5 27 Manufacturir.g burnish Note 1 Steam generator 2 first ISI sample results are C-2 Category. Second ISI Samole 15, 42 HTS + 1.5 15 OD corrosion Note 2-R16 68-HTS + 1.3 5 OD corrosion Note 2 18- -44 HTS + 2.8 10 OD corrosion Note 2 19 66 HTS + 1.2 22 OD corrosion Note 2 20 56 HTS + 1.1 <40 OD corrosion Note 2 21 34 HTS + 1.4 25 OD corrosion Note 2 21: 58' HTS + 1.3 29 OD corrosion Note 2 23 58 HTS +'1.7 33 OD corrosion Note 2 .24. 46 HTS + 0.8 9 OD corrosion Note 2 24-60 HTS + 1.4 10 OD corrosion Note 2 24 66 HTS.+ 1.0 13 OD corrosion Note 2 25 31 AV1 + 0.0 14 AVB wear Note 1 27 33 HTS + 0.7 7 OD corrosion Note 2 .28 56. HTS + 0.6 22 CD corrosion Note 2 '30' 48 HTS + 0.8 18 OD corrosion Note 2 33 49 AV2 + 0.0 19 AVB wear Note 1 1. Steam Generator 2 second ISI sample results are C-1 Category.

m y TABLE 6 (Continued) SEQUOYAH NUCLEAR PLANT UNIT 1 CYCLE 4 INSPECTION APRIL 1990 1H21 CATIONS S/G 2 (Continued) o E2E- ' Cal Location Wall loss CharacterJzation Resolutiqn (%) Non-ISI Sample 6-23 HTS + 1.2 18 OD corrosion Note 2 6 39 .IErS + 1.4 27 OD corrosion Note 2 6 55-HTS,+ 1.3 18 OD corrosion Note 2 8 56 HTS + 1.8 <40 OD corrosion Note 2 8 72 HTS + 1.0 18 OD corrosion Note 2 9 R37 . HTS + 2.0 <40 OD corrosion Note 2 9 58 HTS + 1.1 <40 OD corrosion Note 2 9 58 HTS + 1.6 (40 OD corrosion Note 2 9 66' HTS + 1.8 9 OD corrosion Note 2 10 59 HTS + 1.7 <40 OD corrosion Note 2 10 64 HTS + 1.6 34 OD corrosion Note 2 11' 53 HTS + 1.2 (40 OD corrosion Note 2 F 11 61 HTS + 1.5 39 OD corrosion Note 2 13-33 HTS + 3.5 21-OD corrosion Note 2 13 54 -HTS + 1.7 24 OD corrosion Note 2 13 61 HTS + 1.4 (40 OD corrosion Note 2 14 53 HTS -+'1.7 <40 OD corrosion Note 2 14- '54-HTS + 1.5 29 OD corrosion Note 2 14 55 HTS, 1.5 29 OD corrosion Note 2 14 59 HTS + 1.4 38 OD corrosion Note 2 15 57. HTS + 1.4 <40 OD' corrosion Note 2 15 63 HTS + 1.0 <40 CD corrosion Note 2 16 48 HTS + 0.7 30 OD corrosion Note 2 16 54 HTS + 1.3 34 OD corrosion Note 2 16 55 HTS + 1.2 (40 OD corrosion Note 2 16 57 HTS + 1.3 37 OD corrosion Note 2 17 25 H01 + 37.2 33 Manufacturing burnish Note 1

19' 25 HTS + 1.6-24 OD corrosion Note 2 20' 57 HTS + 1.1 31 OD corrosion Note 2 20-59 HTS +R1.2-25 CD corrosion Note 2 20 61 HTS + 1.3 37 OD corrosion Note 2 21 31 HTS + 1.7

<40 OD corrosion Note 2 21 32 HTS + 1.8 <40 OD corrosion Note 2 21 35 HTS + 1.4 (40 OD corrosion Note 2 21-43 HTS + 1.7 <40 OD corrosion Note 2 21 44 HTS + 1.2 <40 OD corrosion Note 2 21 47. HTS + 1.4 (40 OD corrosion Note 2 22 31 HTS + 1.5 36 OD corrosion Note 2 22 37 HTS + 1.4 <40 OD corrosion Note 2

i I I TABLE 6 (Continued) i SEQUOYAH NUCLEAR PLANT UNIT 1 CYCLE 4 INSPECTION APRIL 1990 j INDICATIONS S/G 2 (C?ntinued) E2E Col Loc a ti_o n Wall loss Characterization Resolution (%) Non-ISI Samole l 22 49-HTS + 1.7 31 OD corrosion Hote 2 .22 51 HTS + 1.9 17 OD corrosion Note 2 j 22 59 HTS + 1.3 32 CD corrosion Note 2 23 52 HTS.+ 1.9 35 OD corrosion Note 2 23 57 HTS + 1.7 <40 OD corrosion Note 2 l 23, 57 HTS + 2.1 (40 OD corrosion Note 2 i .42' 44 AV4 + 0.0 19 AVB wear Note 1 Notess' 1. Reexamine in future outages 2. Reexamine in future outages with specialty exams Anti-Vibration Bar (AVB) J

l 3 TABLE 6 (Continued) SEQUOYAH NUCLEAR PLANT UNIT 1 CYCLE 4 INSPECTION APRIL 1990 INDICATIONS S/G 3 1 a jlqg fatl Location Wall Loss Characterization Resolution (%) ISI Samph 17 48 CTS + 3.5 18 Manufacturing burnish . Note 1 20 87 C01 + 47.9 7 Manufacturing burnish Note 1 21-9 H04 + 44. 27 Manufacturing burnish Note 1 21 9 C03 + 44.3 17 Manufacturing burnish Note 1 33 39-AV2 + 0,0 25 AVB wear Preventively 33 39 AV3 + 0.0 38 AVB wear Plugged 39 56 CTS + 4.2 14 Manufacturing burnish Note 1 Steam Generator 3 ISI Sample results are C-1 Category. j i Non-ISI Samole I' 1 1 HTS + 17.5 26 TLBD wear Note 1 5 94 C04 + 15.3 9 Manufacturing burnish Note 1 19 22 AV3'+ 0.0 22 AVB wear Note 1 .22 64 AV2 + 0.0 15 AVB wear Note 1 22 64 AV3 + 0.0 18 AVB wear Note 1 24 38-HTS + 1.3 36 OD corrosion Preventively Plugged 25 33 HTS + 1.0 22 OD corrosion Note 2 i 29 57 HTS + 1.1 21 OD corrosion Note 2 38 64 AV1 + 0.0 12 AVB wear Note 1 38_ 64 AV2 + 0.0 23 AVB wear Note 1 38 64 AV3 + 0.0 12 AVB wear Note 1 Notest 1. Reexamine in future outages 2. Reexamine in future outage with a specialty exam Tube Lane Biccking Device (TLED) Anti-Vibration Bar (AVB) { q

m. i TABLE 6 (Continued) SEQUOYAH NUCLEAR PLANT UNIT 1 CYCLE 4 INSPECTION APRIL 1990 INDICATIONS S/G 4 si Enx Cal Lpeation Wal: Loss Characterization Resolution (%) Non-ISI Samole 1 1 CTS + 17.7 30 TLBD wear Note 1 11 82 CO2 + 11.3 25 Manufacturing burnish Note 1 14 26 HTS + 3.5 15 OD corrosion Note 2 14 82 C06 + 42.5 21 Manufacturing burnish Note 1 14 82 C06 + 47.2 16 Manufacturing burnish Note 1 15 73 Col + 16.6 20 Manufacturing burnish Note 1 15 75 C01 + 9.l 11 Manufacturing burnish Note 1 t 17 43 HTS - 0.1 >40 Circumferential ID Tube Plugged 18 64 HTS + 0.8 7 OD corrosion Note 2 20 56 HTS + 1.9 28 OD corrosion Note 2 21 S1 HTS + 0.9 29 OD corrosion Note 2 -21 54 HTS + 1.1 24 OD corrosion Note 2 ) 26 43 HTS + 1.0 22 OD corrosion Note 2 22 52 HTS + 1.1 18 OD corrosion Note 2 26 60 HTS + 1.1-9 OD corrosion Note 2 26 86 HTS + 0.8 10 OD corrosion Note 2 28 52 HTS + 1.0 18 OD corrosion Note 2 28 53 C06 + 11.5 19 Manufacturing burnish Note 1 29 31 AV2 + 0.0 14 AVB wear Note 1 40 28 H04 + 36.1 16 Manufacturing burnish Note 1 40 69 C06 + 34.5 23 Manufacturing burnish Note 1 Notes: 1. Reexamine in future outages 2. Reexamine in future outage with a specialty exam Tube Lane Blocking Device (TLBD) Anti-Vibration Bar-(AVB)

't 4 TABLE 7 SEQUOYAH NUCLEAR PLANT UNIT 1 CYCLE 4 INSPECTION APRIL 1990 l PLUGGED TUBE

SUMMARY

'2 M S/G 2 S/G 3 S/G.4 / Previously Plugged. Tubes 10 10 24 19 Tubes Plugged Cycle 4 by Damage Mechanism PWSCC HTS 1 0 0 1 OD Corrosion HTS 0 1 1(1) 0 AVB Wear-0 0 1(1) 0 i TOTAL TUBES PLUGGED 11 11 26 20 1 Primary Water Strsss Corrosion Cracking (PW3CC) Anti-Vibration Bar (AVB) i Note:

1. Tube preventively plugged.

( u TABLE 8 SEQUOYAH NUCLEAR PLANT UNIT 1 CYCLE 4 INSPECTION APRIL 1990 NOMENCLATURE , 4-G Location Nomenclature for'Sequoyah Nuclear' Plant 4 -Notation Description HTE Tube end.- hot leg HTS Top of tubesheet - hot leg H01 First support plate - hot leg t H02 Second support plate - hot leg 'H03 Third support plate - hot leg H04 Fourth support plate - hot leg H05 Fifth support plate - hot leg H06 Sixth support plate - hot leg B07 Seventh support plate - hot leg ' AV1 First anti-vibration bar above H07 D'- AV2 Second anti-vibration bar above H07 'AV3 Second anti-vibration bar above C07 AV4 First anti-vibration bar above C07 C07 Seventh support plate - cold. leg C06 . Sixth support plate - cold leg. C05 Fifth support plate - cold leg. C04 Fourth support plate - cold leg

003 Third support plate - cold leg CO2 Second eupport plate - cold leg C01 First support plate - cold leg CTS' Top.of Tubesheet - cold leg CTE Tube end.- cold leg Indication' locations are designated by an above' listed major location and numeric values in inches above or below a major location.

Positive inches indicates positive elevation (example - HTS + 1.0 is one inch above the hot leg top of tubesheet). 1264q L. L 1- .-}}