ML071360396

Enclosure 2-05/01/2007 Engineering Mechanics Corporation of Columbus Presentation, NRC Welding Residual Stress Solutions as Generated by Battelle and Emc2.

ML071360396
Person / Time
Site:	Wolf Creek
Issue date:	05/01/2007
From:	David Rudland Dominion Engineering, Engineering Mechanics Corp of Columbus
To:	Office of Nuclear Reactor Regulation
MAURICIO GUTIERREZ, RES 301-415-1122
Shared Package
ML071360367	List: ML071360373 ML071360396
References
Download: ML071360396 (18)

Text

NRC Welding Residual Stress Solutions as generated by Battelle and Emc2 David L. Rudland Engineering Mechanics Corporation of Columbus Meeting with Industry regarding Wolf Creek Sensitivity Analyses -

Welding Residual Stresses Dominion Engineering Inc. Offices May 1, 2007 Innovative Structural Integrity Solutions

What have we done, and what is planned Innovative Structural Integrity Solutions Butt Welds only!! See Handout!! 2

What have we done, and what is planned Innovative Structural Integrity Solutions Butt Welds only!! See Handout!! 3

Hot Leg Geometry Alloy 82/182 Butter 12.57 mm Alloy 182 OD = 918 mm 16 15 14 13 12 86.4 mm 11 81 mm 10 9 8 A516-70 SS304 7 6 5 4 3 2 1

SS304 17 ID = 756 mm Innovative Structural Integrity Solutions 4

Path of Maximum Stress Alloy 182 Maximum stress path A516-70 SS304 In many cases, maximum stresses were extracted along a path that was non-planar Innovative Structural Integrity Solutions 5

Weld Centerline Stresses Hot Leg - Ground ID Weld Alloy 182 (max-300 mean)

Weld 200 (max +2 sigma)

Axial Stress (Mpa) 100 Weld (max -2 0 sigma) 0 50 100

-100

-200

-300 Distance from ID (mm)

Material variability Innovative Structural Integrity Solutions 6

Planar versus Non-planar Stresses Hot Leg - Ground ID Weld (2)

Alloy 182 (max-300 mean)

Weld 200 Center (1)

Line Axial Stress (Mpa) 100 Butter 0

(max- (3) mean) 0 20 40 60 80 100

-100

-200

-300 Distance from ID (mm)

(1) at the weld centerline, (2) along the path in the weld where the stresses are highest, and (3) along the path in the buttered region where the stresses are highest Innovative Structural Integrity Solutions 7

Curve-fitting Welding Stresses 1.5 Weld residual stress/Weld yield stress y = -39.381x 4 + 73.31x 3 - 33.189x 2 - 1.0839x + 1.3 1 R2 = 0.9292 0.5 0 Inherent error

-0.5 FE Values

-1 Poly. (FE Values)

-1.5 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Normalized distance fron ID surface Innovative Structural Integrity Solutions 8

With Repair 1.5 Hot leg Hot leg with ID repair Residual Stress/Yield Stress 1

0.5 0

-0.5

-1 0 0.2 0.4 0.6 0.8 1 Nomalized Distance from ID Surface 360 deg - 15% deep ID repair - Last pass ID weld Innovative Structural Integrity Solutions 9

Effects of Diameter 2

Hot leg - no repair Hot Leg - 360 ID repair Residual Stress/Yield Stress 1.5 Surge - 360 ID repair Spray - no repair 1

0.5 0

-0.5

-1 0 0.2 0.4 0.6 0.8 1 Nomalized Distance from ID Surface Innovative Structural Integrity Solutions 10

Effects of Operating Stress 1.4 WRS 1.2 WRS+10ksi 1

Shift WRS by 10ksi 0.8 0.6 WRS/Yield 0.4 0.2 0

-0.2

-0.4

-0.6 0 0.2 0.4 0.6 0.8 1 Normalized distance from ID Stainless Steel weld Innovative Structural Integrity Solutions 11

Effects of Hardening Law Looking at the effects of hardening law on CRDM J-Weld WRS - Will be investigating in Butt Welds!!

0.7 0.6 0.5 Isotropic Hardening 0.4 Kinematic Hardening PEEQ 0.3 0.2 0.1 0

0 2000 4000 6000 8000 10000 12000 14000 Welding Time (s)

One welding pass Steps represent application of other welding passes Innovative Structural Integrity Solutions 12

Drain Line Analysis 2-inch diameter t = 0.54 inch Nozzle Safe end SS weld A182 weld Pipe Butter Machined area About 3t

• Buttering of the nozzle end with A182, 5 passes

• Stress relief of nozzle at 1100F for four hours, cool

• Welding safe-end to the nozzle, A182 weld, 11 passes

• OD weld repair, two passes ground out, and re-weld

• Boring of the welded structure's ID to match pipe ID

• Welding of the SS304 pipe to the safe-end with SS weld, 10 passes

• Hydro testing 125% of 2500psi and room temperature

• Add operating condition, 600F, 2500psi Innovative Structural Integrity Solutions 13

Weld Centerline Stresses 400 Axial stress at weld centerline, MPa 300 200 100 0

-100

-200

-300

-400 0 0.2 0.4 0.6 0.8 1 Distance from ID, inch Innovative Structural Integrity Solutions 14

Weld Stresses on ID 150 End of butter 100 After first weld 50 After second weld Axial stress at ID, MPa 0

First weld centerline

-50

-100

-150

-200

-250

-300 Before hydrotest

-350 0 20 40 60 80 100 120 Distance from second weld centerline, mm Innovative Structural Integrity Solutions 15

WRS at Different Locations 500 After welding the A182 weld, SS weld, hydrotest, and operating conditions 400 300 200 Axial stress, MPa 100 Crack depth 0

-100 End of butter - no butter weld Fusion line - No butter weld End of butter - butter weld + no SR

-200 Fusion - butter weld + no SR End of butter - butter weld and SR

-300 Fusion - butter weld and SR End of butter - butter weld, SR, repair Fusion - butter weld, SR, repair

-400 Upper bound fit Upper bound + Sm

-500 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Normalized Distance from ID Innovative Structural Integrity Solutions 16

Comparison with MRP-106 500 MRP106 400 Emc2 after hydrotest 300 Emc2 after SS weld Emc2 after A182 weld 200 ASME Axial stress, MPa 100 0

-100

-200

-300

-400

-500 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Normalized Distance from ID Innovative Structural Integrity Solutions 17

Plans for Wolf Creek Will be conducting WRS for Wolf Creek Plans are still being developed Some items that may be investigated:

Unusual welding repairs, i.e., SS weld build-up on safe-end A182 filler for thermal sleeve - Also thermal sleeve weld Stainless steel safe end weld Effects of operating loads - plasticity redistribution of WRS Other issues that may arise from this meeting Innovative Structural Integrity Solutions 18