ML18101B117

Responds to GL 92-01,Rev 1,Suppl 1, Rv Structural Integrity

ML18101B117
Person / Time
Site:	Salem
Issue date:	11/20/1995
From:	Eric Simpson Public Service Enterprise Group
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
GL-92-01, GL-92-1, LR-N95198, NUDOCS 9511300053
Download: ML18101B117 (53)

Text

{{#Wiki_filter:t' T ,*\\\\[Tf.i "'///;I'\\>~.... - (; ( \\ ' Public Service

Electric and Gas I Company E. C. Simpson Public Service Electric and Gas Company P.O.. Box 236, Hancocks Bridge, NJ 08038 609-339-1700 Senior Vice P,resident - Nuclear Engineering NOV 2 0 1995 LR-N95198 United States Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 Gentlemen:

GENERIC LETTER 92-01, REV. 1, SUPPLEMENT 1 REACTOR VESSEL STRUCTURAL INTEGRITY SALEM GENERATING STATION UNIT NOS. 1 & 2 FACILITY OPERATING LICENSE NOS. DPR-70 & DPR-75 DOCKET NOS. 50-272 & 50-311 The NRC issued Supplement 1 to Generic Letter (GL) 92-01, Revision 1 on May 19, 1995. Part 1 of the Generic Letter requested licensees to describe those actions planned or taken to locate all data relevant to the determination of reactor pressure vessel integrity, or provide an explanation of why the existing database is considered complete. The Public Service Electric and Gas Company (PSE&G) response to this request was provided to the NRC by Letter LR-N95118 dated August 14, 1995 for Salem Units 1 and 2. To locate additional reactor pressure vessel data which may be relevant to the determination of vessel integrity for Salem Units 1 and 2, tne following actions were committed to be taken: Participation in the Combustion Engineering Owners Group (CEOG) Reactor Vessel Working Group effort to search CE

• records* for additional data pertaining to pressure vessel weld chemistry, including data which may be pertinent to the Salem units.

Participation in Westinghouse Owners Group (WOG) activities related to pressure vessel data compilation including the preparation of a database for vessels in Westinghouse plants. Reviewing the NRC Reactor Vessel Integrity Database (RVID) to locate possible additional data from sister welds in other pressure vessels. Exchanging information with other utilities that have sister heats of materials in their pressure vessels. 28G01.5

t T --- -* ~- . / / Document Control Desk LR-N95198 NOV 2 0 1995 2 PSE&G is required to respond to GL 92-01, Revision 1, supplement 1, Parts 2 through 4 by November 20, 1995. Attachments 1 and 2 provide the response to Parts 2 through 4 for Salem Units 1 and 2, respectively. The responses contained.in Attachments 1 and 2 include an assessment of the best-estimate chemistry values based on completion of the efforts described above to locate additional pressure vessel material data that is applicable to Salem Units 1 and 2. PSE&G continues to participate in the CEOG Reactor Vessel Working Group activity to search Combustion Engineering (CE) records to establish best-estimate copper and nickel contents for beltline weld heats in CE reactor pressure vessels. The volume of information which must be reviewed and compiled into a comprehensive database and report requires a schedule of approximately 18 months to complete. It is expected that the CEOG final report will be issued in December, 1996. PSE&G will assess the CEOG final report when issued to determine if additional evaluation of best-estimate chemistry data is required for Salem Units 1 and 2 in accordance with GL 92-01, Revision 1, Supplement 1. NRC letter dated April 21, 1994 requested PSE&G to provide technical justification for the use of a generic Upper Shelf Energy (USE) value for a Salem Unit 2 weld. PSE&G stated in a letter to the NRC dated June 20, 1994 (NLR-N94114) that it planned to participate in the utility-funded CEOG program for developing generic initial USE values for CE vessel weld metals. The planned effort was to include technical justification for the generic USE values that were developed. PSE&G further stated that it expected to be able to supply the requested information by.December 1995. The CEOG final report CEN-622, "Generic Upper Shelf Values for Linde 1092, 124 and 0091 Reactor Vessel Welds", was issued in June, 1995 and has been included in Attachment 3. The projected End-of-Life (EOL) USE values have been calculated based on the initial generic values, and determined to be greater than 50 ft-lbs. Should you have any questions on this submittal, please contact us. Attachments (3) Affidavit Sincerely,

f Document Control Desk LR-N95198 3 C Mr. T. T. Martin, Administrator - Region 1 U. s. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 Mr. L. N. Olshan, Licensing Project Manager - Salem U. s. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike Mail Stop 14E21 Rockville, MD 20852 Mr. c. s. Marschall (X24) USNRC Senior Resident Inspector Mr. Kent Tosch, Manager, IV NJ Department of Environmental Protection Division of Environmental Quality Bureau of Nuclear Engineering CN 415 Trenton, NJ 0862'5 NOV 2 0 1995

STATE OF NEW JERSEY COUNTY OF SALEM ) ) ) REF: LR-N95198 SS. E. c. Simpson, being duly sworn according to law deposes and says: I am Senior Vice President - Nuclear Engineering of Public Service Electric and Gas Company, and as such, I find the matters set forth in the above referenced letter, concerning Salem Generating Station Unit Nos. 1 and 2, are true to the best of my knowledge, information and belief. --~ / 1 KIMBERLY JO BROWN NOTARY PUBLIC OF NEW JERSEY ? - My Commission Expires April 21, 1998 -'-,_ /Ptiy Commission expires on--------'--------- 'I / J -~.

LR-N95198 ATTACHMENT 1 SALEM UNIT 1 RESPONSE TO ITEMS 2, 3 AND 4 OF GENERIC LETTER 92-01, REVISION 1, SUPPLEMENT 1 REACTOR VESSEL STRUCTURAL INTEGRITY REVISION 0

LR'-N95198

• The Part 2 required response for Generic Letter 92-01, Revision 1, Supplement 1 titled "REACTOR VESSEL STRUCTURAL INTEGRITY" is to contain information provided by PSE&G on three items:

(2) An assessment of any change in best-estimate chemistry based on consideration of all relevant data. (3) A determination of the need for use of the ratio procedure in accordance with the established Position 2.1 of Regulatory Guide 1.99, Revision 2, for those licensees that use surveillance data to provide a basis for the reactor pressure vessel (RPV) integrity evaluation. (4) A written report providing any newly acquired data specified above and (1) the results of any necessary revisions to the evaluation of RPV integrity in accordance with the requirements of 10CFR50.60, 10CFR50.61, Appendices G and H to 10CFR50, and any potential impact on the LTOP or P-T limits in the Technical Specifications, or (2) a certification that previously submitted evaluations remain valid. Revised evaluations and certifications should include consideration of Position 2.1 of Regulatory Guide 1.99, Revision 2, as applicable, and any new data. PSE&G has prepared the following information in response to the requests in the three items. GL92-01 ITEM (2) : Assessment of any change in best-estimate chemistry based on consideration of all relevant data. The following assessments in best-estimate chemistry of the beltline materials have been made. Plate Materials The beltline plate best estimate Cu and Ni values are given in the following table. No new data were located, and therefore there is no change in the assessment of the best estimate chemistries from those in the July, 1995 NRC Reactor Vessel Integrity Database (RVID). SALEM 1 BELTLINE PLATE MATERIALS PLATE HEAT Cu, w/o Ni, w/o B2402-1 C-1354-1 0.24 0.53 B2402-2 C-1354-2 0.24 0.53 B2402-3 C-1397-2 0.22 0.51 B2403-1 C-1356-1 0.19 0.48 B2403-2 C-1356-2 0.19 0.49 B2403-3 C-1356-3 0.19 0.48 2

LR'-N95198

• Weld Materials The following table is a summary of the Salem 1 beltline weld materials, including the best estimate Cu and Ni chemistries.

The bases for the best estimate chemistries are given below. SALEM 1 BELTLINE WELD MATERIALS WELD WELD HEAT TYPE FLUX FLUX Cu, Ni, TYPE LOT w/o w/o 2-042 A,B&C 39B196+Ni200/ Tandem 1092 3692 0.18

1. 09 34B009+Ni200 SAW 3-042 A,B&C 34B009+Ni200 Tandem 1092 3708 0.19 0.98 SAW 9-042 13253 SAW 1092 3791 0.22 0.73 Weld 2-042 A,B&C (Heats 39B196/34B009)

This weld was made with weld heats 39B196 and 34B009 in tandem, with Ni200 nickel wire. There is no known chemical analyses done on the actual tandem weld. Therefore, the best estimate Cu and Ni chemistries were determined by first determining the best estimate values for the two individual heats 39B196 and 34B009, and then averaging the two sets of values. The best estimate for Heat 39Bl96 is based on the Salem 1 surveillance weld. As shown in the following table, the best estimate values for Heat 39B196 are 0.16 Cu and 1.20 Ni. BEST ESTIMATE COPPER AND NICKEL IN WELD HEAT 39B196 SOURCE Cu, w/o Ni, w/o Salem 1 Surveillance (1) 0.16 1.26 Salem 1 Surveillance (2) 0.16 1.14 Sum = 0.32 Sum = 2.40 Average = 0.16 Average = 1.20 (1) "Public Service Electric and Gas Co. Salem Unit No. 1 Reactor Vessel Radiation Surveillance Program", WCAP-8511, November 1975. (2) "Analysis of Capsule Y from the Public Service Electric and Gas Co. Salem Unit No. 1 Reactor Vessel Radiation Surveillance Program", WCAP-10694, December 1984. Best estimate Cu and Ni chemistry values in 34B009 are 0.19 Cu and 0.98 Ni. These values are based on the data in the following two tables. 3

LR'-N95198 ' BEST ESTIMATE COPPER IN WELD HEAT 34B009 SOURCE 111 Cu, w/o WEIGHT Cu w/o x WEIGHT Millstone 1 Surveillance 0.184 1 0.184 Palisades Stm Gen, Region 3 0.185 2 (2) 0.37 HB Robinson Torus-Dome 0.187 1 0.187 Palisades Stm Gen, Region 2 0.190 2 (2) 0.38 Palisades Stm Gen, Region 1 0.190 2 (2) 0.38 Sum = 8 Sum = 1. 501 Average = 0.188 Rounded Avg. (1) Letters from J. Kneeland of Consumers Power dated Oct. 23, 1995 and Nov. 2, 1995. (2) The Palisades steam generator welds have weighting of 2 in the calculation for the weight percent Cu because they are tandem welds. BEST ESTIMATE NICKEL IN WELD HEAT 34B009 SOURCE 1J. 1 Ni, w/o Millstone 1 Surveillance Weld 1.05 HB Robinson Torus-Dome Weld 0.80 Palisades Steam Generator

1. 09 Sum = 2.94 Average = 0.98 (1)

Letter from J. Kneeland of Consumers Power dated October 23, 1995. = As shown in the following table, the PSE&G best estimate Cu and Ni values for the tandem weld 39Bl96/34B009 are 0.18 and 1.09, respectively. PSE&G PSE&G BEST ESTIMATE COPPER & NICKEL IN SALEM 1 WELD 2-042 (HEATS 39Bl96/34B009) Source Cu, w/o Ni, w/o Best Estimate for 39B196 0.16

1. 20 Best Estimate for 34B009 0.19 0.98 0.19 Average = 0.18 Average = 1. 09 Weld 3-042 A,B&C (Heat 348009)

The method for determining the *best estimate chemistries for Heat 34B009 is described in the preceding section of the text under Weld 2-042 A,B&C. The resultant best estimate Cu and Ni values for Heat 34B009 are 0.19 w/o and 0.98 w/o, respectively. 4

LF.-N95198

• Weld 9-042 (Heat 13253)

Best estimate Cu and Ni chemistry values in 13253 are 0.22 Cu and 0.73 Ni. These values are based on the data in the following table. BEST ESTIMATE COPPER AND NICKEL IN SALEM 1 WELD 9-042 (HEAT 13253) SOURCE Cu, w/o Ni, w/o CE Analysis R2083 111 0.73 Adcom Metals Company<2 > --- (3) 0.72 Ft. Calhoun Closure Head <4 > 0.14 0.73 Salem 2 Surveillance <5 > 0.254 0.726 D. c. Cook 1 Surveillance <5 > 0.27 0.74 Sum = 0.664 Sum = 3.646 Average = 0.22 Average = 0.73 (1) Letter PENG-95-379 from S. Byrne of Combustion Engineering, Inc. to J. Perrin of PSE&G, dated November 1, 1995. (2) Adcom Metals Co. analysis dated July 19, 1967 for Heat 13253 shipped to Combustion Engineering, Inc. (3) Reported Cu of 0.07 w/o in Adcom Metals Company analysis suspected as being bare wire analysis, and therefore not included in average. (4) CE average chemical analysis of two samples, per telephone conversation of Oct. 6, 1995 between B. Weber of OPPD and J. Perrin of PSE&G. (5) Average of a total of five Cu and five Ni values from Salem 2 WCAP reports. WCAP-8824 has Cu and Ni values of 0.23 and 0.71. WCAP-11554 has Cu and Ni values of 0.283 and 0.732. WCAP-13366 has Cu values of 0.267, 0.244 and 0.247, and Ni values of 0.728, 0.734 and 0.728. (6) "American Electric Power Service Corp. Donald C. Cook Unit No. 1 Reactor Vessel Radiation Surveillance Program", WCAP-8047, March 1973. GL92-0l Item (3) : Determination of the need for use of the ratio procedure in accordance with the established Position 2.1 of Regulatory Guide 1.99, Revision 2, for those licensees that use surveillance data to provide a basis for the reactor pressure vessel (RPV) integrity evaluation. There is not a need to use the ratio procedure for Salem 1 weld materials, as the weld material in the surveillance capsules is a different heat than any of the Salem 1 beltline welds. GL92-01 Item (4): A written report providing any newly acquired data specified above and (1) the results of any necessary revisions to the evaluation of RPV integrity in accordance with the requirements of 10CFR50.60, 10CFRS0.61, Appendices G and H to 10CFRSO, and any potential impact on the LTOP or P-T limits in the Technical Specifications, or (2) a certification that previously submitted evaluations remain valid. Revised evaluations and certifications should include consideration of 5

Position 2.1 of Regulatory Guide 1.99, Revision 2, as applicable, and any new data. The revised best estimate chemistries determined using newly acquired data require that previous end-of-life (EOL) upper shelf energy (USE), pressurized thermal shock (PTS), LTOP and P-T limit evaluations be revised. Upper Shelf Energy Levels The predicted end-of-life upper shelf energy level has changed for weld 9-042 as a result of a change in best estimate chemistry values. The following table contains the predicted EOL USE values for the beltline materials including weld 9-042. For three of the plate materials, the predictions were made using surveillance capsule Charpy USE data and Fig. 2 of Regulatory Guide 1.99, as described in Position 2.2 of the Regulatory Guide. The predictions for the other materials were made by using Figure 2 of Regulatory Guide 1.99. As shown in the table, all EOL USE predicted values are above 50 ft-lb. PREDICTED END-OF-LIFE UPPER SHELF ENERGY VALUES FOR SALEM 1 BELTLINE MATERIALS PLATE OR Cu, w/o EOL INITIAL PREDICTED METHOD OF WELD FLUENCE

USE, EOL USE DETERMINING AT l/4T, ft-lb AT l/4T, PREDICTION xl0 18 ft-lb B2402-1 0.24 8.5 91 70 Surveillance B2402-2 0.24 8.5 98 83 Surveillance B2402-3 0.22 8.5 104 88 Surveillance B2403-1 0.19 8.2 93 68 Reg Guide 1. 99 B2403-2 0.19 8.2 83 61 Reg Guide 1. 99 B2403-3 0.19 8.2 85 62 Reg Guide 1. 99 2-042 A,B&C 0.18 6.7

96. 2 (l) 68 Reg Guide 1. 99 3-042 A,B&C 0.19 8.2 112 77 Reg Guide 1. 99 9-042 0.22 8.3 112 74 Reg Guide 1. 99 (1) 96.2 ft-lb is lower bound generic initial USE value for Linde 1092 welds per CEOG report ~Generic Upper Shelf Values for Linde 1092, 124 and 0091 Reactor Vessel Welds", CEN-622, June 1995.

PTS Evaluation PTS calculations have been done using the current best estimate chemistries and projected EOL fluences for each of the beltline plates and welds. The results are summarized in the following table. The most limiting material for Salem 1 is weld 3-042C (Heat No. 34B009). The calculated EOL RTPTS is 245 °F, which is well below the PTS screening criterion of 270 °F. 6

I LR-N95198 COMPARISON OF PROJECTED EOL RTprs WITH THE PTS SCREENING CRITERIA FOR SALEM 1 PLATE OR Cu, w/o Ni, w/o EOL FLUENCE PROJECTED PTS WELD AT ID EOL RTPTSt SCREENING SURFACE, xl0 19 OF

CRITERIA, OF B2402-1 0.24 0.53

1. 42 238 270 B2402-2 0.24 0.53

1. 42 184 270 B2402-3 0.22 0.51

1. 42 141 270 B2403-1 0.19 0.48

1. 37 178 270 B2403-2 0.19 0.49

1. 37 193 270 B2403-3 0.19 0.48

1. 37 180 270 2-042 A&B 0.18

1. 09 1.13 238 270 2-042 c 0.18

1. 09 0.74 212 270 3-042 A&B 0.19 0.98 1.18 237 270 3-042 c 0.19 0.98

1. 37 245 270 9-042 0.22 0.73

1. 39 215 300 LTOP and P-T Limits in the Technical Specifications The revised best estimate Cu and Ni values for Salem 1 vary only slightly from those used in previous reactor vessel evaluations, and were evaluated to determine the impact on the current pressure-temperature curves contained in Technical Specification 3/4.4.9.1.

Westinghouse has done an evaluation of the impact of the revised best estimate chemistry values on the P-T curves. The evaluation indicates that the current P-T curves can be used for approximately 24.8 EFPY, which is greater than the current applicability date of 15 EFPY. Salem 1 is currently at approximately 10.8 EFPY. Therefore, the changes in best estimate Cu and Ni values for Salem 1 do not have any impact on the current LTOP or P-T limits. Surveillance Capsule S was recently removed from Salem 1. The analysis of Capsule S will include generation of new heatup and cooldown P-T curves, utilizing the revised best estimate Cu and Ni values. The results of the analysis of Capsule S and any changes to the LTOP or P-T limits will be submitted to the NRC in accordance with 10CFR50, Appendix H. 7

LR'-N95198

• ATTACHMENT 2 SALEM UNIT 2 RESPONSE TO ITEMS 2, 3 AND 4 OF GENERIC LETTER 92-01, REVISION 1, SUPPLEMENT 1 REACTOR VESSEL STRUCTURAL INTEGRITY REVISION 0 8

LR-N95198

• The Part 2 required response for Generic Letter 92-01, Revision 1, Supplement 1.titled "REACTOR VESSEL STRUCTURAL INTEGRITY" is to contain information provided by PSE&G on three items:

(2) An assessment of any change in best-estimate chemistry based on consideration of all relevant data. (3) A determination of the need for use of the ratio procedure in accordance with the established Position 2.1 of Regulatory Guide 1.99, Revision 2, for those licensees that use surveillance data to provide a basis for the reactor pressure vessel (RPV) integrity evaluation. (4) A written report providing any newly acquired data specified above and (1) the results of any necessary revisions to the evaluation of RPV integrity in accordance with the requirements of 10CFR50.60, 10CFR50.61, Appendices G and H to 10CFR50, and any potential impact on the LTOP or P-T limits in the Technical Specifications, or (2) a certification that previously submitted evaluations remain valid. Revised evaluations and certifications should include consideration of Position 2.1 of Regulatory Guide 1.99, Revision 2, as applicable, and any new data. PSE&G has prepared the following information in response to the requests in the three items. GL92-0l Item (2) : An assessment of any change in best-estimate chemistry based on consideration of all relevant data. The following assessments in best-estimate chemistry of the beltline materials have been made. Plate Materials The beltline plate best estimate Cu and Ni values are given in the following table. No new data were located, and therefore there is no change in the assessment of the best estimate chemistries from those in the July, 1995 Reactor Vessel Integrity Database (RVID). SALEM 2 BELTLINE PLATE MATERIALS PLATE HEAT Cu, w/o Ni, w/o B4712-1 C-4173-1 0.13 0.56 B4712-2 C-4186-2 0.12

0. 62 B4712-3 C-4194-2 0.11 0.57 B4713-1 C-4182-1 0.12 0.60 B4713-2 C-4182-2 0.12 0.57 B4713-3 B-8343-1 0.12 0.58 9

LR-N95198

• Weld Materials The following table is a summary of the Salem 2 beltline weld materials, including the best estimate Cu and Ni chemistries.

The bases for the best estimate chemistries are given below. SALEM 2 BELTLINE WELD MATERIALS WELD WELD HEAT TYPE FLUX FLUX Cu, Ni, TYPE LOT w/o w/o 2-442 A,B&C 13253/20291 Tandem SAW 1092 3833 0.22 0.74 3-442 A,B&C 21935/12008 Tandem SAW 1092 3889 0.22 0.86 9-442 90099 SAW 0091 3977 0.20 0.20 Weld 2-442 (Heat 13253/20291) This weld consists of weld heats 13253 and 20291. PSE&G is not aware of any chemical analyses done on this actual tandem weld. Therefore, the best estimate Cu and Ni chemistries were determined by first determining the best estimate values for the two individual heats, and then averaging the two sets of values to get resultant best estimate values for the tandem weld composed of the two heats. The method for determining the best estimate chemistries for Heat 13253 is described in Attachment 1 for Salem 1. The resultant best estimate chemistry values are 0.22 w/o Cu and 0.73 w/o Ni. The best estimate Cu and Ni values for 20291 are 0.22 w/o and 0.74 w/o, respectively. The basis for this determination is given in the following table. 10

• LR-N95198 BEST ESTIMATE COPPER AND NICKEL IN WELD HEAT 20291 SOURCE Cu, w/o Ni, w/o Cooper Surveillance 111 0.21 0.74 Cooper Surveillancec2>

0.23 0.75 Cooper Surveillance<2> 0.22 0.74 Cooper Surveillance <3 > 0.22 0.72 Cooper Surveillance <3 > 0.23 0.77 Cooper Surveillance <3 > 0.23 0.75 Cooper Surveillance <3 > 0.22 0.74 Sum = 1. 56 Sum = 5.21 Average = 0.22 Average = 0.74 (1) "Salem Units 1 & 2 Reactor Vessel Weld Data", Combustion Engineering report prepared for Public Service Electric & Gas, November 1985. (2) "Cooper Nuclear Station Reactor Pressure Vessel Surveillance Materials Testing and Fracture Toughness Analysis", General Electric report MDE-103-0986, May 1987. (3) "Cooper Nuclear Station Vessel Surveillance Materials Testing and Fracture Toughness Analysis", GE-NE-523-159-1292, February, 1993. As shown in the following table, the best estimate Cu and Ni values for the tandem weld 13253/20291 are 0.22 w/o and 0.74 w/o, respectively. BEST ESTIMATE COPPER & NICKEL IN SALEM 2 WELD 2-442 (HEATS 13253/20291) Source Cu, w/o Ni, w/o PSE&G Best Estimate for 13253 0.22 0.73 PSE&G Best Estimate for 20291 0.22 0.74 Sum = 0.44 Sum = 1. 47 Average = 0.22 Average = 0.74 Weld 3-442 (Heats 21935/12008) This weld consists of weld heats 21935 and 12008. Chemical analysis results exist for the combined tandem weld. The methods for determining the best estimate chemistries for the tandem weld are described in the following table. The resultant best estimate Cu and Ni values are 0.22 w/o and 0.86 w/o, respectively. 11

LR'-N95198

• BEST ESTIMATE COPPER & NICKEL IN SALEM 2 WELD 3-442 (HEATS 21935/12008)

SOURCE Cu, w/o Avg. Cu Ni, w/o Avg. Ni for data for data sets sets D Canyon 21.LI 0.22 0.219 0.83 0.871 D Canyon 2, Cap. u<2> 0.219 0.86 D Canyon 2, Cap. u(2) 0.212 0.88 D Canyon 2, Cap. u<2> 0.213 0.90 D Canyon 2, Cap. x<3> 0.225 0.875 D Canyon 2, Cap. x<3> 0.213 0.856 D Canyon 2, Cap. x<3> 0.225 0.877 D Canyon 2, Cap. y!4) 0.196 0.763 D Canyon 2, Cap. y<4l 0.240 0.958 D Canyon 2, Cap. y!4) 0.230 0.910 D Canyon 2 (5) 0.230 0.220 0.90 0.853 D Canyon 2 (5) 0.210

0. 7 6 D Canyon 2 (5) 0.220 0.90 D-7525 16>

0.20 0.21 D-7278 <7> 0.22 Combustion Eng. (8) 0.86 0.86 Sum =0.649 Sum =2.584 Avg.= 0.22 Avg.= 0.86 (1) "Pacific Gas and Electric Company Diablo Canyon Unit No. 2 Reactor Vessel Radiation Surveillance Program", WCAP-8783, December 1976. (2) "Analysis of Capsule U from the Pacific Gas and Electric Company Diablo Canyon Unit 2 Reactor Vessel Radiation Surveillance Program", WCAP-11851, May 1988. (3) "Analysis of Capsule X from the Pacific Gas and Electric Company Diablo Canyon Unit 2 Reactor Vessel Radiation Surveillance Program", WCAP-12811, December 1990. (4) "Analysis of Capsule Y from the Pacific Gas and Electric Company Diablo Canyon Unit 2 Reactor Vessel Radiation Surveillance Program", WCAP-14363, August 1995. (5) "Evaluation of Pressurized Thermal Shock for the Diablo Canyon Unit 2 Reactor Vessel", WCAP-14364, August 1995. (6) Combustion Engineering MML Sample Number D-7525, Heat No. 21935/12008. (7) Combustion Engineering MML Sample Number D-7278, Heat No. 12008/21935. (8) "Salem Units 1 & 2 Reactor Vessel Weld Data", Combustion Engineering report prepared for Public Service Electric & Gas Co., November 1985. 12

• LR-N95198 Weld 9-442 (Heat 90099)

No new data have been obtained for the nickel content. The best estimate Ni content for Heat 90099 is therefore taken as 0.20 w/o, as recommended by CE in the November, 1985 report to PSE&G titled "Salem Units 1 & 2 Reactor Vessel Weld Data". The report states that the nickel content is estimated to be 0.2 w/o, which is taken as an upper limit of nickel contents for Type Mil B-4 wire heats. The best estimate Cu content for Heat 90099 is 0.20 w/o. The basis for this is given in the following table. BEST ESTIMATE COPPER IN SALEM 2 WELD HEAT 90099 SOURCE Cu, w/o WEIGHT Cu w/o x WEIGHT D9248 11> 0.18 1 0.18 D92 95 <1 > 0.17 1 0.17 D8280<2 > 0.09 1 0.09 D8955<2 > 0.17 2 (3) 0.34 D8954<2 > 0.19 1 0.19 Dll313<2 > 0.22 2 (3) 0.44 Dll302 <2 > 0.25 1 0.25 Dll027 <2 > 0.30 1 0.30 Sum =1.96 Average = 0.20 (1) Combustion Engineering analyses D9248 and D9295 are in "Salem Units. 1 & 2 Reactor Vessel Weld Data", Combustion Engineering report prepared for Public Service Electric & Gas Co., November 1985. (2) Letter PEN_G-95-379 from S. Byrne of Combustion Engineering, Inc. to J. Perrin of PSE&G, dated November 1, 1995. (3) A weighting factor of two is used because these are tandem welds. Generic Letter Item (3) : Determination of the need for use of the ratio procedure in accordance with the established Position 2.1 of Regulatory Guide 1.99, Revision 2, for those licensees that use surveillance data to provide a basis for the reactor pressure vessel (RPV) integrity evaluation. There is not a need to use the ratio procedure for Salem 2 weld materials, as the weld material in the surveillance capsules is a different heat than any of the Salem 2 beltline welds. GL92-01 Item (4): A written report providing any newly acquired data specified above and (1) the results of any necessary revisions to the evaluation of RPV integrity in accordance with the requirements of 10CFRS0.60, 10CFRS0.61, Appendices G and H to 10CFRSO, and any potential impact on the LTOP or P-T limits in the Technical Specifications, or (2) a certification that 13

• LR-N95198 previously submitted evaluations remain valid.

Revised evaluations and certifications should include consideration of Position 2.1 of Regulatory Guide 1.99, Revision 2, as applicable, and any new data. The revised best estimate chemistries determined using newly acquired data require that previous end-of life upper shelf energy, pressurized thermal shock (PTS), LTOP and P-T limit evaluations be revised. Upper Shelf Energy Levels The predicted end-of-life upper shelf energy levels have changed for the three beltline welds as a result of the changes in best estimate chemistry values. The following table contains the predicted EOL USE values for the beltline materials including the three welds. For plate material B4712-2, which is the only Salem 2 beltline material in the surveillance capsules, the prediction was made using surveillance Charpy USE data and Fig. 2 of Regulatory Guide 1.99, as described in Position 2.2 of the Regulatory Guide. The predictions for the other materials were made by using Figure 2 of Regulatory Guide 1.99. As shown in the table, no EOL USE predicted values are below 50 ft-lb. PREDICTED END-OF-LIFE UPPER SHELF ENERGY VALUES FOR SALEM 2 BELTLINE MATERIALS PLATE OR Cu, EOL FLUENCE INITIAL PREDICTED METHOD OF WELD w/o AT 1/4T,

USE, EOL USE DETERMINING xl0 18 ft-lb AT l/4T, PREDICTION ft-lb B4712-1 0.13 9.0 106 84 Reg Guide 1. 99 B4712-2 0.12 9.0 97 81 Surveillance B4712-3 0.11 9.0 107 86 Reg Guide 1. 99 B4713-1 0.12

8. 8 98 78 Reg Guide 1. 99 B4713-2 0.12 8.8 103 82 Reg Guide 1. 99 B4713-3 0.12 8.8 121 97 Reg Guide 1. 99 2-442 0.22 6.9

96. 2 (l) 64 Reg Guide 1. 99 A,B&C 3-442 0.22 6.9 114 76 Reg Guide 1. 99 A,B&C 9-442 0.20 8.8

99. 7 <2 >

67 Reg Guide 1. 99 (1) 96.2 ft-lb is lower bound generic initial USE value for Linde 1092 welds per CEOG report "Generic Upper Shelf Values for Linde 1092, 124 and 0091 Reactor Vessel Welds", CEN-622, June 1995. (2) 99.7 ft-lb is lower bound generic initial USE value for Linde 0091 welds per CEOG report "Generic Upper Shelf Values for Linde 1092, 124 and 0091 Reactor Vessel Welds", CEN-622, June 1995. 14

• LR-N95198 PTS Evaluations PTS calculations have been done using the current best estimate chemistries and projected EOL fluences for each of the beltline plates and welds.

The results are summarized in the following table. The most limiting material is weld 3-442A and 3-442C. (Heat No. 21935/12008). The calculated EOL RTPTs is 228 °F, which is well below the PTS screening criterion of 270 °F. PLATE OR WELD B4712-1 B4712-2 B4712-3 B4713-1 B4713-2 B4713-3 2-442 A 2-442 B&C 3-442 A&C 3-442 B 9-442 COMPARISON OF SALEM 2 EOL RTPTs WITH PTS SCREENING CRITERIA FOR SALEM 2 Cu, w/o Ni, w/o EOL FLUENCE AT PROJECTED ID SURFACE, EOL RTPTSf xl0 19 OF 0.13 0.56

1. 51 134 0.12 0.62

1. 51 159 0.11 0.57

1. 51 12 6 0.12 0.60

1. 48 134 0.12 0.57

1. 48 133 0.12 0.58

1. 48 136 0.22 0.74 0.72 182 0.22 0.74 1.16 208 0.22 0.86 1.16 228 0.22 0.86 0.73 201 0.20 0.20

1. 47 125 LTOP and P-T Limits Evaluations PTS SCREENING

CRITERIA, OF 270 270 270 270 270 270 270 270 270 270 300 The revised best estimate Cu and Ni values for Salem 2 materials vary only slightly from those used in previous pressure vessel evaluations, and have a small impact on the current P-T curves contained in Technical Specification 3/4.4.10.1.

Westinghouse has done an evaluation of the impact of the revised best estimate chemistry analysis on the P-T curves. The evaluation indicates that the current P-T curves can be used for approximately 13.8 EFPY, which is somewhat less than the current applicability date of 15 EFPY. This poses no concern since Salem 2 currently is in the range of 8 EFPY, and the curves will be reevaluated around 11 EFPY as part of the Capsule Y analysis. The analysis of Capsule Y will include generation of new heatup and cooldown P-T curves, and will utilize the revised best estimate Cu and Ni values. The results of the analysis of Capsule Y and any changes to the LTOP or P-T limits will be submitted to the NRC in accordance with 10CFR50, Appendix H. 15

ATTACHM:ENT 3 SALEM UNITS 1 AND 2 GENERIC END-OF-LIFE UPPER SHELF ENERGY VALUES REVISION 0 16

LR.-N95198

• The NRC letter of April 21, 1994 to PSE&G states that one open issue was identified by the staff for Salem Unit 2.

The letter states that: "Additional data is required to confirm that the USE at end-of-life is greater than 50 ft-lb because you have provided a generic unirradiated USE value, either a mean value from welds fabricated using the same flux type or a value based on your surveillance material. These types of values are unacceptable because they do not consider heat variability of the unirradiated USE. When the unirradiated USE for a particular heat of material has not been determined, you can determine the lower tolerance limit with 95 percent confidence that at least 95 percent of the population is greater than the tolerance limit. The tolerance limit should be for all welds fabricated by the reactor vessel vendor unless it can be demonstrated that the welds are separable by flux type or other welding variable(s). The licensee must demonstrate that there is a physical (metallurgical) difference in the welds and a statistical difference in the data to utilize a generic unirradiated USE for a particular flux type or other welding variable (s). If the lower tolerance limit results in a projected USE at EOL of less than 50 ft-lb for Salem Unit 2, then you must demonstrate, in accordance with Appendix G, 10 CFR Part 50, that lower values of USE will provide margins of safety against fracture equivalent to those required by Appendix G of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code.ff The letter requested that PSE&G provide a schedule for performing these analyses for Salem Unit 2. PSE&G responded in letter NLR-N94114 of June 20, 1994. In that letter PSE&G stated that the requested information would be supplied by December 1995. The requested information is in the following pages of this attachment. In addition to addressing this question for Salem 2, we are also addressing it for Salem 1. Full Charpy curves were not run on any of the three Salem 1 or three Salem 2 beltline welds. The following table lists pertinent information pertaining to these welds. It also includes the generic initial upper shelf energies which PSE&G is assigning to three of these welds. These generic values were determined during a CE Owners Group study which PSE&G partially funded. The final report on this activity is titled "Generic Upper Shelf Values for Linde 1092, 124 and 0091 Reactor Vessel Welds", and is dated June 1995. A copy of the report is included in the following pages. The report separates Combustion Engineering vessel welds with respect to flux type, and addresses the basis for doing so. The metallurgical analysis of five different flux types, including 17

LR-N95198 Linde 1092 and Linde 0091, concluded that each was unique and, therefore, could result in different properties. The initial upper shelf energy values in the table are mean USE values minus two standard deviations, based on the statistical analyses described in Section 4.0 of the report. Also included in the following table are the projected end-of-life upper shelf energies. These were determined using the copper contents and EOL 1/4T fluences, in conjunction with Figure 2 of Regulatory Guide 1.99, Revision 2. Note that all six welds have projected EOL USE values greater than 50 ft-lb. INFORMATION FOR SALEM 1 AND SALEM 2 WELDS FOR WHICH A GENERIC INITIAL UPPER SHELF ENERGY IS USED PLANT WELD HEAT LINDE Cu, EOL INITIAL PREDICTED FLUX w/o FLUENCE

USE, EOL USE TYPE AT l/4T, ft-lb AT 1/4T, xl 018 '

ft-lb n/cm2 Salem 1 2-042 39B196 1092 0.18 6.7 96.2ll) 68 A,B&C +Ni200/ (generic) 34B009 +Ni200 Salem 1 3-042 34B009 1092 0.19 8.2 112 (3 ) 77 A,B&C +Ni200 Salem 1 9-042 13253 1092 0.22 8.3 112 (4 ) 74 Salem 2 2-442 13253/ 1092 0.22 6.9

96. 2 ll) 64 A,B&C 20291 (generic)

Salem 2 3-442 21935/ 1092 0.22 6.9 114 (S) 76 A,B&C 12008 Salem 2 9-442 90099 0091 0.20

8. 8 99.7' 2 )

67 (generic) (1) 96.2 ft-lb is lower bound generic initial USE value for Linde 1092 welds per CEOG report "Generic Upper Shelf Values for Linde 1092, 124 and 0091 Reactor Vessel Welds", CEN-622, June 1995. (2) 99.7 ft-lb is lower bound generic initial USE value for Linde 0091 welds per CEOG report "Generic Upper Shelf Values for Linde 1092, 124 and 0091 Reactor Vessel Welds", CEN-622, June 1995. (3) Letter from J. F. Opeka (NU) to NRC, dated July 6, 1992.

Subject:

"Generic Letter 92-01 Revision l". (4) WCAP-8824, Public Service Electric and Gas Company Salem Unit No. 2 Reactor Vessel Radiation Surveillance Program", January 1977. (Average of 112, 111.5 and 111.5 ft-lb values for Heat 13253 surveillance material) (5) Letter from G. M. Rueger (PG&E) to NRC, dated June 30, 1992.

Subject:

"Response to Generic Letter 92-01, Revision 1, Reactor Vessel Structural Integrity".

18

COMBUSTION ENGINEERING OWNERS GROUP CEN-622 Final Report GENERIC UPPER SHELF VALUES FOR LINDE 1092, 124 AND 0091 REACTOR VESSEL WELDS Task 839 Prepared for the C-E OWNERS GROUP June 1995 ABB Combustion Engineering Nuclear Operations © Copyright 1995, Combustion Engineering, Inc. / -{/1;5-e-YB02 o{ ( f _, S I pr? jl 1111 111\\1919

LEGAL NOTICE This report was prepared as an account of work sponsored by the Combustion Engineering Owners Group and ABB Combustion Engineering. Neither Combustion Engineering, Inc. nor any person acting on its behalf: A. makes any warranty or representation, express or implied including the warranties of fitness for a particular purpose or merchantability, with respect" to the accuracy, completeness, or usefulness of the information contained in this report, or that the use of any information, apparatus, method, or process disclosed in this report may not infringe privately owned rights; or B. assumes any liabilities with respect to the use of, or for damages resulting from the use of, any information, apparatus, method or process disclosed in this report. Combustion Engineering. Int!.

TABLE OF CONTENTS SECTION TITLE PAGE Table of Contents 2 List of Tables 3 List of Figures 3 1.0 Introduction 4 2.0

Background

4 3.0 Influence of Flux Type On Weld Deposit 6 4.0 Analysis of Upper Shelf Energy Data 12 4.1 Analysis of Welds For Each Flux 13 4.2 Analysis of Variance 13 5.0 Summary & Conclusions 14 6.0 References 16 Page 2 of30

LISI OF TABLES TABLE TITLE PAGE 1 Relative Flux Compositions 18 2 Comparison of The Effects of Fluxes Used for Submerged Arc Welding of RPV Weld Seams 18 3 Manganese/Silicon Ratio of Weld Metals by 19 Flux Type 4 Comparison of Bare Weld Wire & Weld Deposit 20 Chemical Analysis 5 Charpy USE Data for Welds Using Linde 124, 21 1092 & 0091 Flux 6 Statistical Results of Upper Shelf Energy with 23 Welds Using Linde 124, 1092 and 0091 Flux 7 Analysis of Variance for Welds with Linde 124, 24 1092 & 0091 Flux LISI OF FIGURES FIGURE IIILE PAGE 1 Effect of Weld Flux Type on 25 Manganese and Silicon Distribution 2 Histogram of Data for Linde 124 26 3 Histogram of Data for Linde 1092 27 4 Histogram of Data for Linde 0091 28 5 Notched Box and Whisker Plots for Linde 124, 29 1092 & 0091 Flux 6 Cumulative Distribution Function for Linde 124 & 1092 Flux 30 Page 3 of30

1.0 INTRODUCTION

GENERIC UPPER SHELF VALUES FOR LINDE 1092, 124 AND 0091 REACTOR VESSEL WELDS CEOG TASK 839 The purpose of this task is to establish the basis for the use of generic upper shelf Charpy toughness values for Combustion Engineering (CE) fabricated reactor* pressure vessel welds. Generic values are necessary to meet current USNRC requirements for welds fabricated prior to implementation of the requirements of 10 CFR 50 Appendix G (2). Upper shelf energy (USE) values were not determined explicitly for many sets of weld consumables for vessels contracted before 1973. Therefore, generic values of initial USE must be established using the set of available measurements. This report presents an evaluation of those data, and it provides both the statistical and metallurgical bases for the generic values of initial USE for the CE vessel welds.

2.0 BACKGROUND

The Charpy impact test is 'used to measure the toughness of reactor vessel materials. The measurements consist of the absorbed energy (i.e., impact energy), the lateral expansion (an indication of-ductility), and the fracture appearance. These provide evidence of the toughness and ductility of low alloy steel plate and weld material used in the fabrication of CE reactor pressure vessels. The impact toughness can be characterized by an "S-curve" behavior as a function of test temperature. At the lowest temperatures, the material fractures in a brittle mode with relatively little absorbed energy. This is termed the lower shelf toughness region.. At the highest temperatures, the material fractures in a ductile mode with considerable absorbed energy. This is termed the upper shelf region. Between the lower and. upper shelves is the transition region in which the material exhibits a transition from brittle to ductile behavior. The fracture appearance provides a measure of the volume of material fracturing in a cleavage versus a ductile mode. In the upper shelf region, the fracture appearance is fully ductile and the absorbed energy and lateral expansion are at or near their maximums. At temperatures below the upper shelf, the fracture becomes mixed mode with an increasing amount of cleavage fracture as the lower shelf is approached. A definition of USE for reactor vessel materials has been established 'in ASTM Standard Practice E 185-82 (1) as follows: Page 4 of30

"upper shelf energy level - the average energy value for all Charpy specimens (normally three) whose test temperature is above the upper end of the transition region. For specimens tested in sets of three at each test temperature, the set having the highest average may be regarded as defining the upper shelf energy." "Charpy transition curve - a graphic representation of Charpy data, including absorbed energy, lateral expansion, and fracture appearance, extending over a range including the lower shelf energy (less than 5% shear), transition region, and the upper shelf energy (greater than 95% shear)." This definition is being used widely to compute USE for a given base metal or weldment. USNRC regulations (10CFR50, Appendix G) requires that the USE of all reactor vessel beltline materials be measured before plant operation and that the licensee demonstrate that each material meets specific minimum values before and after exposure to fast neutron irradiation (2). The USE toughness requirements of Appendix G based on Charpy impact tests is 75 ft-lb minimum before and 50 ft-lb minit'num after irradiation. The requirement for irradiated USE can be met based on post-irradiation surveillance program measurements of CE fabricated welds (3) or based on predictions, but the latter requires the availability of an initial USE. The practice of developing a full Charpy transition curve for all beltline welds was not implemented until after Appendix G was first issued in 1973. Prior to that time, the ASME Code requirement was to perform three Charpy tests at 1 OF and measure only absorbed energy for a given set of weld consuinables (heat of weld wire and lot of weld flux). Therefore, insufficient data exist for determining an initial USE for many welds which were deposited prior to the implementation of the Appendix G requirements. In numerous instances, full Charpy curves were developed for test plate welds and RPV surveillance program welds. Full Charpy curves are available for weld materials qualified subsequent to the issuance of Appendix G requirements. J;berefore, a moderately sized database does exist which could be used to develop generic values of initial USE in order to demonstrate compliance for those cases in which the data were never generated. The practice instituted by CE in response to Appendix G is to perform weld material certification (WMC) tests for each set of weld consumables; e.g., produce a weldment with a specific heat(s) of weld wire and lot of flux, perform a simulated post-weld heat treatment on it, machine test specimens from it, test the Charpy specimens to develop a full Charpy curve, and perform the other required tests. This practice was also followed prior to 1973 for many weld test plates and surveillance program weldments. Therefore, the older data could serve as the certification tests (i.e., the WMC) for other welds made with the same weld wire heat and lot of flux. This approach was used in numerous cases to comply with the 10CFR50, Appendix G requirement for initial USE. In certain cases, the USE data were applied to welds fabricated with the same wire heat and using an equivalent welding process but a different lot of flux. This was Page 5 of30

considered to be reasonable because an "equivalent" weld process would entail the use of the same types of consumables, meaning the same type of wire and flux. A logical extension of this was to use the available data to establish generic USE values for a group of welds fabricated using an equivalent process. CE used primarily four types of weld flux for reactor vessel beltline weld fabrication during the period of interest (nominally 1964 to 1973). These were ARCOS B-5, Linde 1092, Linde 124 and Linde 0091. Very few values of USE-are available for the ARCOS B-5 welds and, therefore, aren't considered further in this report. USE data for the Linde flux welds, however, are available to the extent that development of one or more generic values is possible. The available USE data show that the welds made using Linde 0091 flux had the highest initial USE, and welds made using Linde 80 flux (the type used by another vessel fabricator for reactor pressure vessel welds) had the lowest initial USE. The Linde 1092 and Linde 124 flux weld USE values were typically in between the Linde 0091 and Linde 80 flux welds. Furthermore, the data grouped by flux type fell within fairly distinct ranges. This distinction was not unexpected because these "neutral" flux types were known to affect the weld puddle differently during welding; i.e., each flux varied in the extent to which constituents were added to or removed from the weld puddle. Based on the need to establish generic values of initial USE for vessel weldments and the observation that USE varied relative to the type of welding flux used, this task was undertaken. Two specific aspects are addressed in the evaluation which follows. The first is to perform statistical analyses to generate best estimate values of initial USE for each flux type and to demonstrate their uniqueness. The second is to provide physical evidence in defense of using separate values of initial USE for each flux type. (Note: The most graphic evidence for a weld flux influence on initial USE is the obvious difference between welds deposited using Linde 80 flux versus the non-Linde 80 beltline welds deposited by CE. This fact should not be overlooked even though the evaluations which follow focus on differences between the non-Linde 80 welds.)

• 3.0 INFLUENCE OF FLUX TYPE ON WELD DEPOSIT Fluxes used in submerged-arc welding are granular, fusible, mineral materials containing oxides of manganese, silicon, titanium, aluminum, calcium, zirconium, and magnesium, and other compounds. Some fluxes may contain intimately mixed metallic ingredients to deoxidize the weld pool or add alloying elements to the weld deposit, or both. The flux is deposited over the welding area and is melted by the heat of the arc. In the molten condition, the flux blankets the weld metal and shields the molten weld pool from atmospheric contamination.

Submerged-arc welding fluxes are generally chemically neutral with respect to the weld metal and must have other characteristics to enable the welding process. All fluxes are likely to produce weld metal deposits of somewhat different composition than that of the weld wire being used. The variations in chemical composition that occur are due to chemical reactions of the flux with the welding arc, Page 6 of30

and, if present, due to the metallic ingredients that may have been added to the flux. Changes in welding parameters, such as arc voltage or travel speed,.will change the quantity of flux interacting with the weld which may affect the resulting chemical composition and or the mechanical properties of the weld deposit (4,5). Submerged-arc welding fluxes are produced in three basic forms: prefused, bonded and agglomerated. Prefused fluxes are made by mixing the various oxide ingredients, melting and solidifying, then crushing to the desired particle size. The advantages of fused fluxes are that:

1)

They are extremely homogeneous in chemical composition,

2) sman particles (fines) can be removed to produce uniform particle size without affecting composition,

3)

They are not hydroscopic, eliminating special storage or drying requirements,

4)

Portions that are unfused after welding can be reused without affecting particle size or composition, and

5)

They are suitable for high travel speeds. The main disadvantage of fused fluxes is that deoxidizers and elements for alloy additions to the weld cannot be readily incorporated in the flux due to the *high temperature processing involved in fusing the flux. Bonded fluxes are produced by mixing all of the desired proportions of ingredients and

• then adding silicates (e.g. water glass) to bond the ingredients together. The mixture is then crushed and screened to the desired particle size. Advantages of bonded fluxes are:

1)

Deoxidizers and metal alloying elements can.be added since they are processed at low temperatures,

2)

The flux density is lower, permitting a thicker layer of flux in the weld zone,

3)

The solidified slag is readily chipped from the weld beads after welding. There are two principal disadvantages of bonded fluxes. Fines cannot be_ removed without altering the composition of the flux. Fines are undesirable because remixing is required to distribute them which adds to the cost of welding. Bonded fluxes are more likely to absorb moisture, thus requiring drying prior to use to avoid affecting the weld process. Moist or damp flux will result in porosity and cracking of the weld metal. The third basic type is agglomerated flux. This type is similar to the bonded flux except that ceramic binders are used in lieu of the silicates used in bonded flux. Since the ceramic binder requires high temperature processing, the use of deoxidizers and alloying elements is limited as in the fused fluxes. Welding fluxes are also characterized by the manner in which they interact with the welding process as either "neutral," "active, n or "alloy. n These terms describe the flux behavior, and generally indicate the amount of manganese and silicon that transfers from Page 7 of30

flux to weld metal (10). Neutral fluxes are defined as those which will not produce any significant change in the weld metal manganese and silicon content as a result of a large change in the welding arc voltage or arc length. Neutral fluxes are primarily used for multiple pass submerged arc welding of heavy sections, as in RPV weld seams. Neutral fluxes contain little or no deoxidizers and rely on deoxidizers in the weld wire to deoxidize the weld pool. While neutral fluxes have the ability to maintain the composition of the weld when welding conditions are changed, the composition of the weld deposit will be affected by the type of flux being used. Some oxides in the flux may break down under the heat of welding releasing oxygen which can decarburize the weld puddle, resulting in a weld deposit that may have lower carbon content than the starting electrode or wire. Other fluxes contain manganese silicate which can also decompose under heat adding manganese and silicon to the weld metal, even though they are not present as intentional alloying elements in the flux. Elements such as chromium from the weld wire can also be affected by the action of neutral fluxes on the weld pool. These factors have to be addressed by the welding engineers when selecting weld wire and flux combinations for submerged arc welding. The changes in chemical composition that occur are fairly consistent for a given type of neutral flux over a range of variation in welding parameters. However, the changes will vary, sometimes considerably, between different types of neutral fluxes. Active fluxes contain intentional additions of manganese or silicon or both. These are added as deoxidizers to provide increased resistance to porosity and weld cracking resulting from contamination by the base materials being joined. Substantial amounts of manganese and silicon can be transferred to the weld metal by 5uch fluxes (10). Because of this action of the flux on the welding process, cleanliness of the material and contaminants such as oxides, oils or grease on the base metals are* not as critical as when using neutral fluxes which do not have strong deoxidizing action on the weld pool. The manganese and silicon contents of welds deposited with active fluxes will be affected by changes in welding parameters. Increases in manganese or silicon increase strength levels of weld metal but may lower impact properties. -Because of the tight welding controls that would be required to maintain uniform composition and properties in multi-pass welds using these types of flux, active fluxes are more typically used to make single pass welds. Alloy fluxes, as the name implies, are those which add specific alloying elements to the weld deposit. They are used with carbon steel electrodes to make alloy steel weld deposits. The desired alloying elements are added as ingredients to. the flux which then mix with the weld metal to form an alloyed deposit. The basis for selecting the weld wire and flux type for vessel welding depended on a variety of important factors:

1)

Ability of welds to meet the required strength and toughness requirements (now including the 10 CFR 50 Appendix G upper shelf energies),

2)

Availability in the large quantities required, Page 8 of30

i

f.

3)

. Ease of detaching slag from the weld beads,

4)

Ability to produce weld deposits with minimum number of defects and frequency of necessary repairs, and S) The relative cost of the flux as part of the welding process. The ability to meet the required strength and toughness requirements is affected by the chemical composition of the weld deposit and by the welding. parameters. Both the filler

• wire and the flux composition can alter the weld metal composition, affecting weld bead morphology, microstrucmre and mechanical properties (6).

However, the specific alloying content of the weld deposit is less of a factor than the flux type in influencing notch toughness. Modification of the flux composition, which removed silicon and oxygen and reduced inclusion content, was found to have a much greater influence on the toughness properties of submerged arc welds than modifying the alloy content (6). C-E shops used neutral fluxes for submerged arc welding of reactor pressure vessel (RPV) weld seams, including ARCOS BS, Linde 1092, Linde 0091 and Linde 124. ARCOS BS, an agglomerated type flux, was used in the fabrication of several older vessels. Its use was discontinued in the mid-1960's when difficulties making consistent welds were attributed to variations in the flux being supplied. Over a period of time, the CE shops used the three Linde fluxes which are all fused neutral type fluxes. The fluxes were selected to minimize charges to the weld deposit chemistry. There were no metallic elements intentionally added to any of these flux types. The primary purpose of the flux was to provide the shielding of the deposit required by submerged arc welding to prevent contamination of the weld. Fluxes were preferred which limited silicon, oxygen and inclusion content in the deposit to improve toughness properties. Linde 1092 was the flux type selected after problems arose with the ARCOS BS type flux. The changeover to Linde 1092 initially resulted in difficulty in meeting the tensile strength requirements. To address this problem and meet production schedules, nickel was added to the weld deposit. This nickel addition welding process was discontinued after the shop was able to procure nickel alloyed welding wire. Vessel welds were fabricated by both of these welding processes using Linde 1092, up until the time the Linde company discontinued production of this flux type. Linde 0091 flux was the next type to be qualified and used by the CE shops. Problems with the consistent performance of the flux, similar to those experienced with the ARCOS BS, also occurred with Linde 1092 and 0091. This led to the qualification of Linde 124 to obtain better consistency. Experience showed that, although higher toughness properties were obtained with the Linde 0091 flux, fewer weld indications were encountered with the Linde 124 flux which reduced the required number of weld repairs. Many of the indications reported from radiographic examinations of Linde 0091 welds turned out to be "ghost indications" (i.e., not real defects). However, the presence of the indications still necessitated actions which impacted the shop production schedule. The improved performance of Linde 124, coupled with the fact that it was readily available and less expensive, resulted in its use for welding of many vessel components (11). Page 9 of30

t One measure of the effectiveness of the flux in maintaining the clean1iness of the weld deposit is the Basicity Index (Bl). One formula for estimating BI from the flux composition (cited in Reference 6) is given as: Cao +/- CaF2 +/- MaO +/- KzO +/- Na20 +Uz.O +/- 1h(Mn0 +/- FeO) Si02+ 1h(Al20 3 +/-Ti02 +/- ZrOi) In general, it has been found that the higher the basicity index of the flux, the cleaner the weld deposit will be (fewer nonmetallic inclusions). Oxygen recovery by the weld metal has been reported to be a function of BI (12). However, the index alone is not the sole indicator of oxygen potential. The flux components which tend to form suboxides in the presence of the weld plasma are in the denominator of the formula. When the fraction of these flux components is small, the BI becomes large even though the resultant volume of suboxides (and, therefore, inclusions) is small. The basicity index can be considered as a measure of the tendency of flux components to dissociate into suboxides and oxygen in the weld plasma, which can contaminate the weld pool. It has also been reported that high-flux basicity will reduce weld metal oxygen levels with a resultant increase in toughness properties (6,7). The relative flux compositions for Linde 80, Linde 124 and Linde 0091 are shown in Table 1 (8). The BI values for the ARCOS BS and Linde fluxes used in RPV fabrication are shown in Table 2, along with qualitative comparisons of the effect of weld flux type on several weld parameters. The Linde 80 flux type shown in Table 2 was not used by the C-E shops for RPV welding. Linde 80 was used by other vessel manufacturers and is included in Table 2 just for purposes of comparison to the Linde flux types used by C-E. As seen in Table 2, the basicity index, as determined from the relative composition and the formula above shows a uniform trend of increasing BI value for the flux types with improved upper shelf energy. Another factor influencing the toughness properties of submerged arc welds is the oxygen content of the welds. The oxygen level of weld metals is influenced by many factors such as the deo:X.idizers present (silicon, manganese, aluminum, etc.), welding process and welding conditions. CaF2 and Ti02 additions were found to be beneficial in improving weld metal toughness. The Linde 80 and 124 fluxes are very similar, except for the increased fluoride content of Linde 124. Linde 124 welds exhibit significantly better upper shelf properti~s than Linde 80 deposits. Oxygen contents were lower and silicate inclusions were fewer and smaller in welds using fluxes modified with such elements. Oxygen content in the weld metal affects the weld metal transformation behavior, influencing the resulting microstructure of the weld and thus, influencing the toughness properties (6). One study reported that the weld metal oxygen content dropped from 900 ppm to 300 ppm for a basicity index change from 0.5 to 1.5 and then tended to remain constant with increasing flux basicity (7). Page 10 of30

Manganese and silicon are other elements that can vary in the weld metal as a function of the type of flux being used. High silica slags may result in increased silicon deposits. Manganese in the weld wire will tend to be oxidized by the welding process. The resulting composition of the weld will, therefore, tend to have lower manganese content than the wire. Depending on the composition of the flux being used, manganese can also* be picked up by the weld metal from the molten flux to replace some or all of the manganese being oxidiz.ed. Manganese can be restored to the weld pool either by additions of metallic manganese to the flux or additions of manganese oxide (MnO).

• Manganese-silicates can break down in the heat of the weld introducing manganese and silicon to the weld pool. Free oxygen generated by these reactions can also enter the molten weld pool, contributing to the oxygen content and resulting loss of toughness described above. These slag/metal reactions may also significantly affect the resultant dissolved oxygen and inclusion content which influence the mechanical properties as described above (9). Increases in manganese content can increase the yield and tensile strength of weld metal but generally, does not have a significant effect on the toughness properties. Manganese in the *weld metal helps to promote an acicular microstructure in the weld metal which in mm produces good cleavage resistance.

The primary role of silicon in the welding process is in the deoxidation of the weld pool. Silicon can also reduce the inclusion volume of the weld metal when it is kept low in proportion to the manganese content. Increasing the manganese/silicon ratio helps reduce the volume of inclusions which can have beneficial effects on tensile strength and resistance to microvoid coalescence (9). The manganese/silicon ratios of weld deposits made using the three Linde fluxes are shown in Table 3. Figure 1 shows the manganese and silicon distributions for Linde 0091, 1092 and 124 fluxes. Comparison of the distribution8 reveals very similar composition between Linde 1092 and 0091 but higher manganese and significantly higher silicon in the Linde 124 weld deposits. Table 4 shows comparisons of the bare wire and weld deposit chemical analyses using two different flux types with the same heat of weld wire. Four cases (A, B, C and D) are given in which two or three flux types were used to deposit welds with the same wire heat. In general, differences in weld deposit analysis can be attributed to the flux types used. Comparisons in Table 4 confirm that for a given heat of weld wire, significant differences in deposit chemistry occur depending on the type of flux used. The most notabl~ differences are for manganese and silicon as described above. For example, Weld Wire Heat A welded with Linde 0091 and 124 fluxes show more silicon is picked up and more manganese is recovered in the weld with Linde 124 when compared to the Linde 0091 deposit. Weld wire heat B, in Table 4, provides a comparison of three Linde fluxes. There is an increasing level of manganese recovered in the weld deposit as the flux basicity index (see Table 2) increases. The silicon level is nominally the same for 0091 and 1092 in the weld. Linde 124 flux resulted in a higher silicon content than the other two fluxes. Chemical analyses for wire heats C and D compare the composition of Linde 0091 and Linde 1092 welds with the composition from Linde 80 flux using the same heats of weld wire. Significantly higher manganese and silicon contents resulted from the use of Linde 80 flux. As shown in Page 11 of30

Table 2, the effects of the Linde 80 flux on weld deposit tend to produce the lowest USE values of any of the four Linde fluxes considered. Other elements, in particular phosphorus, sulfur, nitrogen and other impurities, could have significant effects on weld metal toughness, but no clear trends were observed for any of these elements as a function of the type of flux. In summary, Linde 80, 1092, 124 and 0091 are all neutral fluxes, but they differ in the degree of neutrality. This difference is proportional to the basicity index; the higher the index, the cleaner the weld and the lower the oxygen content of the weld. Cleanliness and low oxygen contents tend to produce higher USE results. Chemical analysis results for weld deposits support the literature findings regarding variability of manganese and silicon by flux type. Therefore, since Linde 1092, 0091 and 124 differ in basicity index, the welds deposited using these different flux types can be expected to differ in cleanliness, oxygen content, manganese and silicon content, and general microstructure. 4.0 ANALYSIS OF UPPER SHELF ENERGY DATA The purpose of this section is to establish best estimates of the USE for welds made with three different Linde weld fluxes. In addition, the statistical uniqueness of the USE database for the three flux type welds is to be demonstrated. The applicable Charpy USE data (13) for welds using Linde 1092, 0091 and 124 fluxes are compiled in Table 5. The analysis presented below establishes the mean and standard deviation of the USE for each type of weld. Analysis of Variance was used to demonstrate independence of the weld types. The tests used were the F Test (16), Kruskal-Wallis Test (17), and Komogorov-Smimov Test (15). 10 CFR 50, Appendix G (2) currently requires that reactor vessel beltline materials must exhibit an initial USE of at least 75 ft-lb. For many vessels, compliance with this requirement cannot be established because many welds lack USE measurements. Generically-based USE values could be used in these cases to enable compliance. Currently, the use of generic mean initial values for other properties in lieu of specific material data is acceptable to the NRC. For example, generic values for initial RTNDT may be used for RTPTs analysis if measured values are not available. Therefore, there is a high degree of confidence that the use of generic USE values will be acceptable to the NRC as long as it can be demonstrated that both physical and statistical evidence exists to support unique USE values for each flux type. The objective of this analysis is to establish the statistical basis. The physical evidence was discussed in the previous section. To determine generic USE values for these three weld flux types, ABB reviewed the original fabrication records maintained in our Chattanooga facility. The available Charpy data contained in both the ABB database and in the *Power Reactor Embrittlement Database, Version 2 (18) were collected. Page 12 of30

Table 5 gives the Charpy USE data for the welds for each flux type. In Section 4.1, the three flux types are analyz.ed assuming that they are three different populations. The analysis of variance that justifies treating the three flux types as separate populations is provided in Section 4.2. 4.1 Analysis of Welds for Each Flux Type Figures 2 through 4 give the histograms for the Charpy data for the three treatments of welds. Using a normal distribution, mean, variance, standard deviation, upper quartile, and lower quartile values are given in Table 6. Figure 5 gives a notched box and whisker plot for the three weld types. The whiskers represent the first quartiles. The box represents 50% of the data. The center line of the box is the median value and the ends of the notch represent the 95 % confidence interval of the median. For Linde 0091 flux welds, the data points outside the whiskers represent outliers. Welds with Linde 0091 flux are shown to have significantly higher USE than welds with the other two fluxes. The mean, sum and variances for the three fluxes given in Table 6 were calculated with both EXCEL (Version 5.0, Ref. 14) and STATGRAPlilC PLUS (Version 6, Ref. 15). Consistent results were obtained from both codes. 4.2 Analysis of Variance A one way analysis of variance was performed to demonstrate that the flux types (treatments) produced independent populations. The most common test is the F Test (16). Variations of the samples about the mean for each treatment are compared with variations of the values between the treatments. The null hypothesis states that if the treatments are equal then each treatment has the same mean and variance and the variance between treatments is z.ero. The F Test compares the ratio of the mean variation between the treatments with the mean variation within the treatments. This ratio is compared with the ratio predicted in a F distribution for the appropriate degrees of freedom and confidence level. Table 7 gives the results of this analysis and concludes that the three flux types are independent. The F Test was performed with both EXCEL and STATGRAPlilCS. The equations for the F Test were taken from Ref. 16 and programmed into EXCEL. In a separate calculation the initial data were analyzed using STATGRAPlilCS. Both analyses produced the same results for sums, treatment means, grand means, and F ratios. Figure 5 shows that welds with Linde 124 and Linde 1092 flux are closer to each other than welds with Linde 0091 flux. A separate F Test was performed for these two flux types and concluded that they were independent. In addition, a Page 13 of30

Kolmogorov-Smirnov Test of these flux types was performed. These results are given in Table 4. The Kolmogorov-Smirnov Test compares the cumulative distribution functions (CDF) of two types (see Figure 6) and looks for the maximum vertical distance between the CDFs. Again, the test concludes that the USE of the Linde 124 and Linde 1092 flux type welds are independent. Separate two group analysis of the welds with Linde 0091 flux and the other fluxes was not performed because Linde 0091 was shown to have significantly higher USE (Figure 5). The Kruskal-Wallis Test (17) (also called the H Test) for the three flux types was also performed. This test compares the sum of the ranking of the samples for the treatments instead of the means. It, therefore, is less sensitive to the effects of outliers. It is a non-parametric method that does not require normally distributed samples. The Significance level (0) was less than the confidence interval (0.05) and, therefore, the null hypothesis is rejected and the three flux types are assumed to be independent. 5.0

SUMMARY

& CONCLUSIONS

1.

CE reactor welds were fabricated primarily with four types of welding flux, Linde 1092, Linde 0091, Linde 124 and ARCOS B5. ARCOS B5 data were too limited in number for statistical analysis. CE did not employ Linde 80 flux for reactor vessel beltline welds.

2.

Following the issuance of 10CFR50, Appendix G, welds were tested to determine the upper shelf energy (USE) toughness. Prior to the issuance of Appendix G, USE measurements were not routinely obtained. This necessitated a generic approach to establishing USE.

3.

The statistical analysis results are given in Table 6 and summarized below: Linde 124 Linde 1092 Linde 0091 Mean USE, ft-lb 102.3 112.4 150.3 Standard Deviation 9.4 8.1 25.3

4.

The analysis of variance concluded that the populations of USE values for the three weld flux types were independent.

5.

The metallurgical analysis of five different flux types concluded that each was unique and, therefore, could result in different properties. Tables 1 through 4 and Figure 1 describe these differences which are Page 14of30

r.. summarized as follows. Each flux type is neutral, but they vary in the degree of neutrality (passivity). The upper shelf energy is related to the basicity of the weld flux: Linde 80 Linde 124 Linde 1092 Linde 0091 Mean USE, ft-lb 69.7(Ref. 19) 102.3 112.4 150.3 Basicity Index 1.09 1.25 (not 1.47 available) The correlation is likely to be a function of the relative cleanliness of the weld deposit. The higher the Basicity Index, the cleaner the weld deposit (in terms of, e.g., inclusion content) can be assumed to be. Variations in alloy content should have a smaller influence on the USE of the weld deposit. Certain elements such as manganese and silicon which vary consistently as a function of flux type should, therefore, have only a small effect on USE.

6.

Generic values of initial upper shelf energy toughness based on flux type are clearly justified. The different flux types have unique metallurgical effects in the weld puddle and in the resultant weld deposit. The resultant upper shelf energy varies in proportion to the basicity index of the welding flux. The USE values for each flux type are found to represent independent populations based on analysis of variance. Therefore, generic values of USE based on flux type are valid for use with CE fabricated vessel weldments.

7.

The following conservative values of initial USE are recommended for use in satisfying 10 CFR 50, Appendix G requirements: Flux Type Linde 124 Linde 1092 Linde 0091 Lower Bound USE (ft-lb) 83.5 96.2, 99.7 The preceding are the mean USE minus two standard deviations based on the statistical analyses described in Section 4.0. Page 15 of30

6.0 REFERENCES

1)

"Standard Practice for Conducting Surveillance Tests for Light-Water Cooled Nuclear Power Reactor Vessels", ASTM Designation E185-82, American Society for Testing and Material.

2)

"Fracture Toughness Requirements", Title 10, Code of Federal Regulations, Part 50, Appendix G.

3)

"Evaluation of Low ClWpy Upper Shelf Energy Materials", CEOG Report CEN-604, Revision 1, August 1993.

4)

Metals Handbook Yol. 6 Welding and Brazini. American Society for Metals, Metals Park, Ohio, 1977.

5)

SF.A 5.23 (ANSl/AWS A 5.23), Appendix A, "Guide to AWS Specification for Low Alloy Steel Electrodes and Fluxes for Submerged Arc Welding," ASME Boiler & Pressure Vessel Code, Section II, Part C, American Society for Mechanical Engineers, New York, NY, 1992.

6)

J. E. Indocoehea and D. L. Olson, "Relationship of Weld-Metal Microstructure and Penetration to Weld-Metal Oxygen Content," J. Materials for Energy Systems, Vol. 5, No. 3, December 1983, pp. 139-148.

7)

T. W. Eagar, Welding Journal, Vol. 57, 1978, p. 76s.

8)

L-TEC Submerged Arc Welding Fluxes, Material Safety Data Sheet, ESAB Group, Inc. Form 7960, Dated Mar. 31, 1993.

9)

K. E. Dorschu, "Factors Affecting Weld Metal Properties in Carbon & Low Alloy Pressure Vessel Steels," Welding Research Council Bulletin No. 231, WRC, New York, NY, October 1977.

10)

G.D. Uttrachi, "Selecting Fluxes for Submerged Arc Welding: What You Should Know About Them," Welding Design & Fabrication, Vol. 78, Feb. 1978, pp. 78-

79.

11)

J. D. Varsik, "Evaluation of the Effect of Weld Flux on Irradiation Sensitivity," Combustion Engineering, Inc. Report MCM-79-180, December 1979.

12)

C. S. Chai and T. W. Eagar, "Predictions of Weld-Metal Composition During Flux-Shielded Welding," J. Materials for Energy Systems, Vol. 5, No. 3, December 1983, pp. 160-164. Page 16of30

13.

C.D. Stewart, "Generic Upper Shelf Energy for CEOG Vessel Welds," ABB Report PENG-95-042, March 21, 1995.

14.

EXCEL Version 5.0, Microsoft Corp.

15.

STATGRAPIIlCS Plus, Statistical Graphics System By Statistical Graphics Corporation, Version 6, 1992.

16.

Probability and Statistics, Spiegel, M.R., McGraw-Hill Book Company, 1975.

17.

Modem Elementary Statistics, Freund, J,\\.E., Prentice-Hall, Inc., 1984.

18.

"PR-EDB: Power Reactor Embrittlement Database, Version 2", Oak Ridge National Laboratory Report ORNL/TM-10328/R2 (NUREG/CR-4816), January 1994.

19.

A.S. Heller and A.L. Lowe, Jr., "Correlations for Predicting the Effects of Neutron Radiation on Linde 80 Submerged-Arc Welds", Babcock & Wilcox report BAW-1803, January 1983. Page 17 of30

TABLE 1 RELATIVE FLUX COMPOSmONS FLUX FLUORIDES TYPE Cao (e.g. CaFi.) MgO MnO FeO Si02 Al203 0091 <50 <15 0 0 <2 <40 0 124 <25 <20 <10 7 <2 <40 15 80 <25 <7 <15 8 <2 <40 15 TABLE2 COMPARISON OF THE EFFECTS OF FLUXES USED FOR SUBMERGED ARC *WELDING OF RPV WELD SEAMS RELATIVE PROPERTIES TYPE BAS I CITY BASICITY OXYGEN OXYGEN& OF OF INDEX POTENTIAL SILICON FLUX SLAG "BI" OF SLAG CONTENT LINDE80 LOWEST 1.09 HIGHEST HIGHEST I I I LINDE 124 I 1.25 I I ARCOSB5 I I I I I I LINDE 1092 I I I I I I LINDE0091 HIGHEST 1.47 LOWEST LOWEST Linde 80 flux not used in the fabrication of C-E RPV welds.

• • Lmde 1092 & ARCOS B5 Fluxes are no longer produced, therefore relative compositions could not be obtained to calculate the BL The sequence of these two flux types in the relative order of properties shown has been estimated qualitatively.

Ti02 <10 0 0 UPPER SHELF ENERGY LOWEST I I I I I I HIGHEST Page 18 of30 1 l

TABLE3 MANGANESE/SILICON RATIO OF WELD METALS BY FLUX TYPE Flux Type Sample Size Average Ratio Mn/Si Standard Deviation 0091 87 7.11 1.60 1092 24 6.56 2.58 124 108 3.08 0.72 Page 19 of30

WIRE HEAT A WIRE HEAT B WIRE HEAT c WIRE HEAT D TABLE4 COMPARISON OF BARE WELD WIRE & WELD DEPOSIT CHEMICAL ANALYSES FLUX TYPE Mn Si s p BARBWIRE 1.91 0.07 0.021 0.016 0091 1.24 0.17 0.017 0.020 124 1.40 0.35 0.019 0.019 FLUX TYPE Mn Si s p BARBWIRE 1.94 0.05 0.012 0.010 124 1.29 0.33 0.011 0.016 0091 1.12 0.18 0.009 0.013 1092 1.27 0.14 0.010 0.015 FLUX TYPE Mn Si s p BARBWIRE 1.86 0.02 0.025 0.015 0091 1.12 0.14 O.Q15 0.014 80 1.40 0.52 0.018 0.013 FLUX TYPE Mn Si s p BARBWIRE 1.91 0.05 0,010 0.012 1092 1.15 0.21 0.012 0.021 80 1.43 0.50 0.012 0.018 Mo Ni Cu 0.54 . NIA 0.08 0.49 0.01 0.09 0.47 0.01 0.13 Mo Ni Cu 0.55 NIA 0.12 0.52 NIA 0.32 0.51 NIA 0.30 0.49 NIA 0.27 Mo Ni Cu 0.53 NIA 0.10 0.53 NIA 0.27 0.52 NIA 0.29 Mo Ni Cu 0.57 0.05 0.09 0.56 NIA NIA 0.52 NIA NIA Page 20 of30

TABLES CHARPY USE DATA FOR WELDS USING LINDE 124, 1092 & 0091 FLUX 90069 125.7 90154 102.3 1P3571 126.0 83637 237.3 87603 143.3 90067 124.3 90209 100.7 12008/21935 121.0 4P6519 224.0 90077 143.3 89827 118.3 91762 100.3 W5214 120.0 90067. 215.0 90130 143.3 83637 116.7 89476 100.0 W5214 118.0 90211 212.0 90209 142.7 4P7927 116.3 90128 99.3 3277 118.0 4P6052 200.3 33A277 142.7 4P7927 115.7 3P7317 98.3 305424 112.0 90077 187.0 89022 141.3 90077 115.7 LP2P8374 98.3 W5214 112.0 4P6524 177.3 83646 141.0 90132 115.0 90157 98.0 12008/20291 112.0 89833 171.7 3P7150 139.3 89833 113.3 5P7388 97.7 13253 111.0 90128 167.3 90132 139.0 90071 112.7 90069 97.6 1P3571 105.0 88114 166.3 SP7388 139.0 90159 112.7 3P7246 97.3 39B196 104.0 90069 161.7 83640 137.7 90077 112.3 4P7869 97.3 305414 104.0 90154 160.0 10137 137.0

• 89408 110.7 3P7150 97.0 27204 98.0 33A277 160.0 90159 136.0 3P8013 110.0 5P9028 96.7 V89476 158.0 89024 135.7 3P7802 109.7 90146 96.7 83650 154.0 3P8349 135.0 4P8632 109.3 651A708 96.3 90132 153.7 83653 134.3 89828 109.3 89828 96.0 87003 153.0 90136/10137 132.0 LP5P9744
• 109.0 89833 95.7 87005 152.0 87000 131.7 Page 21 of 30

TABLE6 STATISTICAL RESULTS OF UPPER SHELF ENERGY WITH WELDS USING LINDE 124, 1092 & 0091 FLUXES Linde Flux Type Variable: 124 1092 0091 Sample size

68.

13.

60.

Mean USE, ft-lb 102.3 112.4 150.3 Mean - 2 std. dev. 83.5 96.2 99.7 Median USE, ft-lb 102.5 112. 145. Variance 88.5 65.4 638. Standard deviation, ft-lb 9.41 8.09 25.3 Range, ft-lb

43.

28.

132.6 Lower quartile, ft-lb 95.85 105. 137.4 Lower 95% Conf. Mean, ft-lb 97.9 102.3 147.1 Upper 95 % Conf. Mean, ft-lb 106.7 122.4 153.5 Upper quartile, ft-lb 109.15 118. 153.8 Coef. of variation, ft-lb 9.19 7.20 16.81 Page 23 of30

TABLE7 ANALYSIS OF VARIANCE FOR WELDS WITH LINDE 124, 1092 & 0091 FLUXES One Way F Test of 3 Fluxes Grand Mean, ft-lb Variation between treatments Variation within treatment Total Variation F (Calculated) F (Table, 95% Conf.) 123.7 75159. 44383. 119543. 116.8 3.07 Result: F(Calc.) > F(Table), Null Hyp0thesis is rejected. Kolmogorov-Smirnov Test (Linde 124 & 1092 only) Estimated overall stat. DN Significance Level (SL) Confidence Interval (CI) 0.516 0.00601 0.05 Result: SL < CI, therefore Null Hyp0thesis is rejected. One Way F Test (Ljndel24 & 1092 only) Variation between treatments Variation within treatment Total Variation F (Calculated) F (Table, 95% Conf.) 1103. 6712. 7815. 13.0

4.0 Result

F(Calc.) > F(Table), Null Hypothesis is rejected. Kruskal-W allis Test (3 Fluxes) Test Statistic Significance Level (SL) Confidence Interval (CI) 100.0 0.0 0.05 Result: SL < CI, therefore Null Hypothesis is rejected. Page 24 of30

FIGURE 1 EFFECT OF WELD FLUX TYPE ON MANGANESE AND SILICON DISTRIBUTION 50 40 0 z 30 w

l c 20 w

a:'

u.

10 0 10 6 z 6 w

l c 4

w a: 0

u.

2 0 0 0 0.4 0.8 1.2 1.6 SILICON & MANGANESE FOR LINDE 0091 2 (wt.%) 0.4 0.8 1.2 1.6 SILICON & MANGANESE FOR LINDE 1092 2 (wt.%) 0.4 0.8 1.2 1.6 SILICON & MANGANESE FOR LINDE 124 2 (wt.%) Page 25 of30

FIGURE2 IDSTOGRAM OF DATA FOR LINDE 124 FLUX 20 18 16 14 12 0 z w

J C3 10 w

0: 8 LL 6 4 2 0 ---t-------------------~** 60 80 100 120 140 160 UPPER SHELF ENERGY (ft-lb) Page 26 of30

( .L t.,/ 0 z w

J 0 w a:

LL 5 4 3 2 1 0 FIGURE3 HISTOGRAM OF DATA FOR LINDE 1092 FLUX

• • t-----------------t**-

60 80 100 120 140 160 UPPER SHELF ENERGY (ft-lb) Page 27of30

l

• If

() z w

J CJ w

a:

u.

FIGURE4 HISTOGRAM OF DATA FOR LINDE 0091 FLUX 16 .. ;........................... i........................... ;........................... :*********.. *****************'******"'*******************1****....................... i.. 14 .. j........................... !...........................,........................................................ :.......................... l.......................... : 12 .. ~*.......................... : ........................... ~ ~ ~ 10 8 6 4 2 ............

• 1*.......................... ~..

0 i:..:.:.:.~----~---*---1.:.* :i:::u::.~~:.u:.:£:.::.l::.:J.::.:.L::.:1~~=-:l _[l ________ _J_ 80 110 140 170 200 230 260 UPPER SHELF ENERGY (ft-lb) Page 28of30

250 225 200 .0 I b 175 (!J er: w z w 150 LL _J w I CJ) 125 er: w a.. a.. 100

J 75 50 FIGURES NOTCHED BOX AND WIIlSKER PLOTS FOR LINDE 124, 1092 AND 0091 FLUX

• • ~***....... ***********..... :............. *!******************************.......... -~;............................ ***********~************........ *********************!..

~ ~ 1 j ii ~ 1

• • ~*****************************************!*****************************************?*********************************************************************************!**

= \\ ~ l

• • j****************************************j*******....,............................ r**************....................... ~....................................... r 0

~ ~

• • 1*........................................ :.... ********* ****************************~ *******************....... **************......... ************************* *******:**
    • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • J;*********************************

.. 1............................... :.... 2.................................. ~.:............. : ...................... ~........................................ 1.. l I

• • ~*****************************************r****************************************r******.. ***********.. ******************r****************************************r*

~ ~ .. ~-........................................ ~-....................................... *;........................................ ~-........................................ ~.. LINDE 1092 LINDE 124 LINDE 0091 Key to Plot TYPE OF LINDE FLUX Upper Quartile _Mean Median Lower Quartile 0 Outliers Page 29of30

-r.. ~ *. *s;I

• ..:f i

.>~ i '** FIGURE6 CUMULATIVE DISTRIBUTION FUNCTION FOR LINDE 124 AND 1092 FLUX 1 0.9 .. ;................................. ;................................. ;................................ (................................. ;.............................,.. ~ul8E124** + z 0 0.8 I-0 <( a: 0.7 ll. z 0 0.6 I-

J CD a:

0.5 I-en 0 0.4 iJJ > 5 0.3

J

~ 0.2

J 0

i LINDE 1092 --~*********************************:*********........................ !.......................................................... r***:***.............................. !.. + : ~

• • r................... :.............

~................................. ~.............................. r***************--****;--~**--*r**.............................. ~.. ~ ~ l ~ of',,

• • <*******.......................... :................................................................ (................................ :....................................

i I i ~ I + ..,................................ l................................ L.... ************************'******'*************************~********************************:..

• • 1',,*******

mJ,,* Ji ~ L ~ ~ .. i................................ t,' ********************.........L.............. "f..* ~...*..*..** i................................ i................................ ~.. I I i i

• • ~=,,_********************************-r,,, ***********.................. :............ i................... i................................ l...... :......................... L I

i i i ,,"w f f 0.1 0,, ~T: 1 I 80 90 100 110 120 130 UPPER SHELF ENERGY (ft-lb) Page 30 of30}}