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Structural Steel Welding Presentation
	ML20133B738
Person / Time
Site:	Wolf Creek, 05000000
Issue date:	02/27/1985
From:	; KANSAS GAS & ELECTRIC CO.
To:	;
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'i STRUCTURAL STEEL WELDING PRESENTATION KANSAS GAS AND ELECTRIC COMPANY WOLF CREEK GENERATING STATION FEBRUARY 27, 1985

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KG&E/NRC MEETING

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AWS STRUCTURAL STEEL WELDING PHILLIPS BUILDING

BETHESDA, MARYLAND

FEBRUARY 27,1985 INTRODUCTION i

NRC

KG&E - Gene Rathbun; Manager Licensing and Radiological Services GENERAL DESIGN PHILOSOPHY James Ivany; Civil Engineering Supervisor, Bechtel l

QUALITY ASSURANCE PROGRAM AND HISTORY OF CORRECTIVE ACTION REPORT NO.19 William Rudolph; Manager Quality Assurance (WCGS) i WELDING HISTORY AND MANAGEMENT PLAN John Berra; Vice President - Operations, Daniel International Corporation ENGINEERING EVALUATION Jerry Brown; Civil Engineering Group Leader, Bechtel i

INDEPENDENT REVIEWS Glenn L. Koester; Vice President - Nuclear

Roger Reedy; Professional Engineer, Reedy Associates' i

Dr. John Fisher; Professor of Civil Engineering, Lehigh University

Dr. Geoffrey Egan; President, APTECH

SUMMARY

Glenn L. Koester 1

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STRUCTURAL STEEL WELDING IS DONE TO l

AWS D1.1 - 1975 i

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AWS IS NOT CODIFIED l

CODE APPLICATION BY OWNER -

l ARCHITECT / ENGINEER

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I KG&E SUBMil i ALS TO NRC CONCERNING AWS STRUCTURAL STEEL WELDING 10CFR50.55(e) REPORTS

October 17, 1984 - KMLNRC 84-187

January 18, 1985 - KMLNRC 85-025 l

FINAL REPORT

December 31, 1984 - KMLNRC 84-238 l

January 21, 1985 - KMLNRC 85-037 SUPPLEMENTAL INFORMATION l

February 14, 1985 - KMLNRC 85-054

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February 15, 1985 - KMLNRC 85-057

February 18, 1985 - KMLNRC 85-058

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STORA E N COMMUNICATION CORRIDOR BLDG.

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FUEL BLDG.

REACTOR BLDG.

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,6i EXTERIOR CONCRETiE WALL EMBEDDED PLATE

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CONCRETE SLAB INTERIOR CONCRETE WALL I

MAXIMUM BEAM REACTION FLOOR PLAN

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i The design, fabrication, erection, and i

inspection of welded connections in struc-tural steel for buildings are governed by the following standards:

Structural Welding Code AWS D1.1, developed i

by the Structural Welding Committee of the l

American Welding Society (AWSD

Specification for the Design, Fabrication, and l

Erection of Structural Steel for Buildings, developed by the American Institute of Steel Construction (AISC) i

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d Allowable shear stresses for fillet welds are set at 30 percent of the weld metal ultimate tensile strength, whereas the ultimate shear strength is in the range of 65 to 75 percent of ultimate tensile strength.

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E7018 WELD METAL 80-(MINIMUM) 60-C 0-v ASTM A36 BASE MATERIAL m 40_

(MINIMUM) m La CE F-W 20-BASIC ALLOWABLE STRESS O

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0 0.04 0.08 0.12 0.16 0.20 0.24 STRAIN (infin)

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Allowable stresses are specified at a level below ultimate capacity for several reasons, including the following:

Load Definition i

. Vanations in Materials and Construction

j BASIC DESIGN MARGINS l

STRUCTURAL STEEL WELDED CONNECTIONS

~

CONSERVATI\\/E CODE ALLOWABLES CONSERVATIVE DEFINITION OF LOADS l

CONSERVATIVE USE OF MINIMUM MATERIAL l

STRENGTHS MINIMlZED VARIATIONS IN MATERIALS AND CONSTRUCTION l

PLUS CONSERVATIVE ENVELOPING OF MULTISITE EARTHQUAKES

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l CONSERVATIVE DESIGN METHODOLOGY CONSEQUENCE CONSIDERATIONS l

I EQUALS LARGE FACTORS OF SAFETY AGAINST FAILURE M

c KG&E QUALITY ASSURANCE PROGRAM.

OVERVIEW i

10 CFR 50, APPENDIX B I

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KG&E QUALITY ASSURANCE PROGRAM FOR DESIGN AND CONSTRUCTION INDEPENDENT AUDIT / SURVEILLANCE PROGRAM lDENTIFICATION, CONTROL, AND RESOLUTION OF HARDWARE AND PROGRAMMATIC DEVIATIONS i

c CORRECTIVE ACTION PROGRAM

NONCONFORMANCE REPORTS

CORRECTIVE ACTION REQUESTS / REPORTS

OTHER CORRECTIVE ACTION VEHICLES ow*

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AWS D1.1 STRUCTURAL STEEL WELDING CONCERNS BACKGROUND INFORMATION

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DiC CORRECTIVE ACTION REPORTS

WELD DEVIATIONS JJ #B4dke# mph l

RECORD RETRIEVABILITY A 5-372 //#

H//Asf fit-f&spium-5 dMdf W.s NRC TASK FORCE 4, @4S[//#3 l

CONCERNS WITH DIC CAR RESOLUTION l

KG&E RE-EVALUATION OF DlC l

CAR RESOLUTION ADDITIONAL s

NRCINPUTS DOCUMENT RECONCILIATION LIMITED WELD RE-INSPECTIONS i

POTENTIAL 50.55(e)

KG&E QA CORRECTIVE ACTION REQUEST NO.19

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KG&E CAR NO.19 MANAGEMENT ACTION PLAN 1

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l KG&E QA CORRECTIVE

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l ACTION REQUEST NO.19 PROGRAM OBJECTIVES

DOCUMENT A CONSOLIDATED PROJECT PLAN l

ASSURE BY OBJECTIVE EVIDENCE THAT AWS D1.1 SAFETY-RELATED STRUCTURAL STEEL l

WELDING COMPLIES WITH ALL O.UALITY CRITERIA.

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ASSURE THAT INSPECTION DOCUMENTATION REFLECTS APPROPRIATE INFORMATION AND IS:

i AVAILABLE

COMPLETE l

TRACEABLE l

EVALUATE OTHER AWS D1.1 SAFETY-RELATED WELDING ACTIVITIES l

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d KG&E QA CORRECTIVE ACTION REQUEST NO.19 FINDINGS

- OVERVIEW

MISSING WELD RECORD DOCUMENTATION

WELD DEVIATIONS i

WELDS NOT MADE/ MISSING MATERIAL

PRESENCE OF WELD INSPECTION DOCUMEN-l TATION WITHOUT PRESENCE OF WELD

VERIFICATION OF COMPLETED CORRECTIVE ACTION TO KG&E SURVEILLANCE REPORT S-372 l

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l KG&E CAR NO.19 MANAGEMENT

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ACTION PLAN QA VERIFICATION PROCESS

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TWO EXPERIENCED Q.A AUDITORS ASSIGNED ON A FULL-TIME BASIS

IN-PROCESS SURVEILLANCES WERE PERFORMED

A THOROUGH AUDIT OF EACH CORRECTIVE ACTION STEP WAS PERFORMED i

RESULTS OF THE AUDIT AND SURVEILLANCES:

CAR No.19 Management Action Plan was Effective

CAR No.19 Findings were Satisfactorily Resolved

KG&E QA CORRECTIVE ACTION REQUEST NO.19 j

SUMMARY

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KG&E QA CAR 19 RECOMMENDED CORRECTIVE l

ACTIONS - READILY ADOPTED i

l

KG&E MANAGEMENT ACTION PLAN - EXCEEDED i

l CAR 19 RECOMMENDATIONS THUS PROVIDING A l

MORE COMPREHENSIVE TREATMENT OF AWS i

D1.1 WELDING CONCERNS

RE-INSPECTION OF VIRTUALLY ALL SIGNIFICANT l

SAFETY-RELATED STRUCTURAL STEEL WELDING -

l WITH AND WITHOUT RECORDS l

EVALUATION OF OTHER AWS D1.1 SAFETY-RELATED WELDING PROGRAMS l

EVALUATION OF OTHER SAFETY-RELATED

.i PROGRAMS BEYOND AWS D1.1 i

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_StMWtY OF STRUCTIRAL STEEL EltECTION E3ILDING 1977 1978 1979 1980 1981 1982 1983 1984 AIDtILIAftY C

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AWS D.1.1 -75 o

DESIGN OF WELDED CONNECTIONS

WORKMANSHIP i

FILLER M ETAL REQUIREMENTS

WELD PROCEDURE QUALI FICATION

WELDER QUALIFICATIONS o INSPECTION ff. A22 m

N SCELLANEOUS STRUCTURAL STEEL WELD RECORDS MSSWR i l; l

o DRAWING NUMBER o JOINT NUMBER AREA / LOCATION o

o BASE MATERIAL PIECE OR HEAT NUMBER o ROD WITH DRAWAL DATA o FILLER MATERIAL HEAT NUMBER /

LOT NUMBER o WELD PROCEDURE o WELDER IDENTIFICATION NUMBER o OUALITY INSPECTOR

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. WELD AI i RIBUTES TO BE INSPECTED PER AWS D1.1-75 e

PRESENCE

FUSION

LOCATION

PROFILE

LENGTH

OVERLAP

SIZE

POROSITY

UNDERCUT

ARC STRIKES

CRACKS

SLAG.

CRATERS

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WELDING HISTORY

SUMMARY

ERECTION / WELDING PERFORMED IN 1977-1981

WELDING PROGRAM WAS IN ACCORDANCE WITH AWS D.1.1-1975 I

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CAR 19 MANAGEMENT PLAN

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PROGRAMMATIC REVIEW

WELDERS O.UALIFIED IN ACCORDANCE WITH AWS D.1.1-75

WELDING PROCEDURES IN ACCORDANCE WITH AWS D.1.1-75

FILLER MATERIAL PURCHASE AND CONTROL IN ACCORDANCE WITH AWS D.1.1-75

INSPECTION CRITERIA COMPLIED WITH AWS D.1.1-75

INSPECTORS CERTIFIED TO ANSI 45.2.6

DOCUMENTATION IN ACCORDANCE WITH AWS D.1.1 AND ANSI 45.2

KG&E SURVEILLANCE REPORT S-372 CLOSURE VERIFICATION

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CAR 19 MANAGEMENT PLAN WELDING HARDWARE REVIEW j

DEVELOPMENT OF SECONDARY INSPECTION PROCEDURES CERTIFICATION OF INSPECTORS IDENTIFICATION OF STRUCTURALLY SIGNIFI-i j

CANT JOINTS BY ENGINEER VALIDITY OF INSPECTION IN PRESENCE OF l

PAINT FIREPROOFING REMOVAL.

INSPECTION OF STRUCTURALLY SIGNIFICANT JOINTS 4

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l CAR 19 MANAGEMENT PLAN WELDING HARDWARE REVIEW j

(Continued)

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INVESTIGATION OF MISSING WELDS WITH l

PRIMARY RECORDS

DOCUMENTING CONSTRUCTED CONFIGURATION OF JOINTS 1

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EVALUATION OF CONSTRUCTED CONFIGURA-l TION BY THE ENGINEER i

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REWORKING JOINTS

ISSUANCE OF

SUMMARY

REPORT e

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ACCEPTABLE RETURN WELD ACCEPTABLE PROFILES l

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UNDERRUN

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j CAR 19 MANAGEMENT PLAN CONCLUSIONS I

QA PROGRAM DEFICIENCIES CONFINED TO CAR 19 ISSUES 1

PRESENCE OF WELD INSPECTION DOCUMENTA-TION WITHOUT PRESENCE OF WELDING WAS CAUSED BY HUMAN ERROR i

WELD RECORD RETRIEVABILITY PROBLEMS DID NOT CARRY OVER TO OTHER PROGRAMS

WELDING PROGRAM IS IN ACCORDANCE WITH AWS D.1.1-75

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ALL' QUALITY CRITERIA AS SPECIFIED IN THE I

SUMMARY

BY GLENN L. K0 ESTER 2/27/85 KGaE HAS ALWAYS HAD, AND CONTINUES TO HAVE A FIRM i

6 6

i COMMITMENT TO PROTECT THE HEALTH AND SAFETY OF THE PUBLIC AS WELL AS OUR OWN EMPLOYEES.

THAT IS WHY WE UNDERTOOK SU H AN EXTENSIVE PROGRAM TO EVALUATE THE ACCEPTABILITY OF THE STRUCTURAL STEEL WELDING AT WOLF CREEK.

AS YOU HEARD EARLIER, OUR REINSPECTION EFFORTS FOUND SEVERAL MINOR DEVIATIONS THAT GAVE THE APPEARANCE OF A HIGHER THAN EXPECTED REJECT RATE.

HOWEVER, THE PRIMARY REASON FOR THESE REJECTS RESULTED FROM THE "N0 TOLERANCE" INSPECTION PHILOSOPHY DISCUSSED BY MR. REEDY.

THE VAST MAJORITY OF THESE DEVIATIONS WOULD NOT BE REJECTED BY A QUALIFIED AWS INSPECTOR AT ANOTHER FACILITY UNLESS THEY WERE MAKING THE SAME TYPE SECONDARY INSPECTION THAT WE MADE.

THE FACT THAT KG8E TOOK A MORE CONSERVATIVE APPROACH DURING THE REINSPECTION EFFORTS DOES NOT IN ANY WAY INVALIDATE THE INITIAL i

WELD INSPECTIONS.

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AS DISCUSSED EARLIER, THE REINSPECTIONS DID IDENTIFY A FEW I

JOINTS IN WHICH SOME WELDS HAD NOT BEEN MADE.

THESE PRIMARILY Lt RESULTED FROM A MISINTERPRETATION OF THE WELD DETAIL AND NOT FROM GROSS INADEQUACIES IN THE INSPECTION PROGRAM.

white WE STRIVE FOR PERFECTION, WE MUST RECOGNIZE THAT HUMAN ERRORS CAN AND DO OCCUR.

THAT IS ONE REASON WHY WE DESIGN AND BUILD THESE PLANTS WITH S0 MUCH CONSERVATISM.

THIS IS DEMONSTRATED BY THE l

I FACT THAT NONE OF THE JOINTS WITH MISSING WELDS WOULD HAVE f

FAILED.

A POINT THAT NEEDS TO BE EMPHASIZED IS THAT WE MEAN IT WOULD NOT HAVE FAILED UNDER THE WORST POSTULATED LOADING i

CONDITIONS.

THIS WOULD INCLUDE NORMAL LOADING PLUS ANY LOADS RESULTING FROM A POSTULATED WORST CASE ACCIDENT.

OUR PRIMARY OBJECTIVE IN THE OVERALL CORRECTIVE ACTION PROGRAM DISCUSSED EARLIER WAS TO ASSURE THAT WOLF CREEK IS STRUCTURALLY SOUND AND WILL NOT FAIL UNDER THE WORST POSTULATED

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ACCIDENT CONDITIONS.

WE HAVE DONE THAT.

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1 ;. e IN DOING SO, WE ALSO REAFFIRMED THAT THE AWS WELDING WAS DONE IN ACCORDANCE WITH THE APPLICABLE CODES.

nil WE DID NOT LIMIT OUR REVIEW OF THIS MATTER TO WELDING i

ALONE.

WE ALSO LOOKED AT OTHER AREAS TO ASSURE THEY WERE i

COMPLETED IN ACCORDANCE WITH APPLICABLE REQUIREMENTS AND IN A MANNER THAT PROVIDES ADEQUATE PROTECTION OF THE HEALTH AND SAFETY OF THE PUBLIC.

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WE ALSO HAD THREE OF THE LEADING AUTHORITIES IN STRUCTURAL

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STEEL WELDING INDEPENDENTLY REVIEW OUR PROGRAM TO ASSURE THAT WE WERE NOT TAKING A BIASED LOOK AT OURSELVES.

AS YOU HEARD FROM THEIR DISCUSSIONS TODAY, FROM THEIR REVIEW 0F THE VARIOUS ASPECTS OF OUR PROGRAM, hE DID A VERY THOROUGH, CONSERVATIVE, ASSESSMENT OF OUR AWS WELDING PROGRAM AND THEY FOUND NOTHING TO QUESTION OR INVALIDATE THE CONCLUSIONS WE HAVE MADE.

l 1 SINCERELY BELIEVE THAT ANYONE KNOWLEDGEABLE IN i

ENGINEERING AND CONSTRUCTION PRACTICES WOULD HAVE TO AGREE THAT KG8E'S CORRECT!YE ACTION PROGRAM VERIFIED THAT THE STRUCTURAL STEEL AT WOLF CREEK GENERATING STATION IS SAFE AND SOUND. s

, -THIS COMPLETES OUR PRESENTATION ON AWS STRUCTURAL STEEL WELDING AT WOLF CREEK.

WE FIRMLY BELIEVE THE RECORD IS CLEAR AND jff. ARE READY TO RECEIVE OUR OPERATING LICENSE AND COMMENCE LOADING FUEL AND PROCEED THROUGH POWER ASCENSION.

4 6

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!3 g-UNITED STATES NUCLEAR REGULATORY COMMISSION j

wAsmNGToN, D. C.20SSS NOViS6.4

.Ci MEMORANDUM TO:

FILE FROM:

Sang B. Kim, Structural Eng heer-Structural Engineering Section B Structural and Geotechnical Engineering Branch Division of Engineering SUSJECT:

RESPONSE TO THE TECHNICAL ASSISTANCE-REQUEST ON WOLF CREEK WELD JOINTS INSPECTIOH PROGRAM (see Reference below).

~

Reference:

Herorandum for P. G. Eisenhut of NRR from R. P. Denise of Region IV, " Request for Technical Assistance Work Creek Generating Station DN S0-482" dated November 2, 1984.

In response to the Region IV TA request (Reference) the following visits were made to the Bechtel facility located in Gaithersberg,!!D.

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On November 6, 1984, D. Smith and S. Kim of NRC met with J. Ivany A

(Group Supervisor) and P' Carrat (Staff to Chief Engineer) of Bechtel

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and discussed general procedure for selecting structurally significant joint for inspe'ction, method of disposition of painted connection, imbedded joint and Honconformance Reports (HCRS).

On November 13, 1984, S. Kim met with J. Ivany, G. Brown (Civil Design Leader), L. Rctando (Project Manager) and K. Lee (Chief Engineer) and discussed justification of deficient weld disposition and it' bedded joint configuration.

As a result of our review, it is concluded that Bechtel's inspection program and corrective actions being developed and utilized with regard to Wolf Creek field weld joints are adequate. Further details are provided in the enclosure.

Bechtel has agreed to perform calculation to provide further technical justification for disposition of weld overrun NCRs. We Axpect to review the calculation when it becomes available in ea December f

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,5 g B.-)[im Structural Engineer Structpfal Engineering Section B Structural and Geotechnical Engineering Branch Division of Engineering b

cc: See next page.

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D. Crutchfield P. Kuo G. Lear D. Smith L. Martin 6

R. Denise C. Tan

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4 ENCLOSURE (fo

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e. g 4N REVIEW 0F BECHTEL'S CORRECTIVE ACTION FOR WOLF CREEK WELD DEFICIENCIES t

1.

SELECTION PROCESS OF STRUCTURALLY SIGNIFICANT WELD Bechtel's current definition of structurally sig~nificant weld joints l

j is basically same as the one given in the Corrective Action Request 19 j

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dated October 17, 1984. As inspection progress and experience l

accumulates the following items are identified as exceptions to the 4

structurally signific, ant joints (as of 11/13/84):

1.

handrails t

2.

toeplates

,3.

grating 4.

checked plate

. ~ 2, 5.

stairs and supportin'g steel i

6.

ladders i

7.

monorails 8.

temporary construction welds s

Two independent checks are being made for completeness of selection of the joints; one at Gaithersburg and one at the Wclf Creek site.

Also fabrication, erection and field work drawings of American Bridge, Bechtel and Cives St, eel are used for any given building to insure that all the significant joints are included.for the inspection.

(No shop welds are part of the scope). Majority of the field weld connections are located along the exterior or interior concrete walls and, therefore, identifjcation of the fie]d_ weld is relatively a straight forward -

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,,.., task. Additional effort is made to include all the interior._..

field weld to the steel columns by paying specia.1 attention to the notes on the drawing that call for anything other than bolted.

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connections.

In view of the above, likelihood of omitting any significant field welds from inspection is believed to be small.

t 2.

Imbedded Connections We were told that there are approximately a dozen beamsy mbedded in i

the concrete' walls.

Bechtel is waiting for the results.of the chrentongoingjointinspectionbeforerecommendinganyaction on the imbedded connections. They may elect not to inspect imbedded joint when the current inspection results were found to be satisfactory.

Otherwise, they will evaluate an alternative load path of the beam, namely that concrete will take up the load rather than.the joint thus eliminating need for inspecting them.

We do not see any deficiency in the approach.

3.

Deficient Welds Corrective Action Following is the Bechtel's outline of the weld corrective action:.

"All weld deviations which resul,t in a violation of the design allowable stresses specified in the SNUPPS Civil-Structural Design Criteria 10466-C-0 are unacceptable and the weld will be repaired.

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ca-I Missing welds and missing portions of weld (greater than 1. inch

. nominally) are una.ce.eptable regardless of the stress levels in the

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joint and the welds will be installed unless specifically approved

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otherwise by the engineer.

Defects (cracks, lack of fusion, undercut, etc.) which jeopardize the integrity of the joint are unacceptable and will be repaired.

The engineer will perform a case by case review of each weld

.s inspection report in order to identify those defects which require l

repair".

In accepting under sized welds, Bechtel performed calculation l

demonstrating that design allowable stress are not exceeded with as built weld size.

However, disposition of weld overrun had only a qualitative justification as shown in the following example:

NCR-ISN-20569-CW.

s "Since the provided' weld is longer than the length required by design calculations, the connection is acceptable with regard to strength considerations using the assumed pin-ended beam design assumption.

The ends of the upper return welds may exhibit some -

tearing due to a stress concentration from additional moment

. attracted by the increased fixity of the clip angles.

However, this condition is'self limiting since the tearing will reduce, and

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may tdtally eliminate"th'e'ad'ditional attra'cted moment.

Tearing,

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.,..althoughnotpreferable,shallnotheopardizet'hedesignload..

carrying capability of.the connection".

This particular NCR concerns clip angle welded on imbedded plate on the wall.

Additional weld on the upper part of the clip angle (horizontal run) will introduce moment to the imbedded plate prior to tearing away from,the wall.

Bechtel agreed to look into the moment capacity of the imbedded wall by mean of a specific t

calculation and inform us of the result.

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ML20133B738

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