ML042660368
| ML042660368 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 06/30/2004 |
| From: | Hyres J BWXT, BWXT Services |
| To: | Framatome ANP, Office of Nuclear Reactor Regulation |
| References | |
| ORNL/NRC/LTR-04/15 1140-025-02-24 | |
| Download: ML042660368 (28) | |
Text
BWXT SERVICES, INC.
1140-025-02-24 94 Knoop Hardness (500 gram) 0.0 50.0 100.0 150.0 200.0 250.0 300.0 350.0 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 0.55 0.60 0.65 0.70 0.75 Distance, inches Microhardness, HK Stainless Clad Low Alloy Steel Figure 4.2.7: Microhardness data and low magnification photograph for Sample B2C2B3.
BWXT SERVICES, INC.
1140-025-02-24 95 Figure 4.3.1: Tensile specimen design (dummy test specimen shown).
BWXT SERVICES, INC.
1140-025-02-24 96 Tensile Test Comparison 0
10 20 30 40 50 60 0
5 10 15 20 25 30 35 Engineering Strain (%)
Engineering Stress (ksi)
B2C2A1 B2C2A2 B2C2A1 B2C2A2 UTS 54,800 psi 57,100 psi 2% Offset YS 30,500 psi 31,300 psi Elongation 28.7%
28.7%
Reduction in Area 39.3%
34.3%
Figure 4.3.2: Tensile test results for specimen B2C2A1 (near RCS) and specimen B2C2A2 (near low alloy steel).
BWXT SERVICES, INC.
1140-025-02-24 97 Specimen B2C2A1 ~1.8X Specimen B2C2A2 ~1.8X Figure 4.3.3: Low magnification photographs of tensile specimens after test.
BWXT SERVICES, INC.
1140-025-02-24 98 B2C2A1 5X B2C2A2 5X Figure 4.3.4: Higher magnification photographs showing fracture location of tensile specimens.
BWXT SERVICES, INC.
1140-025-02-24 99 Table 5.1: Sample identification listing for Piece A2A.
Sample ID Location Test Plan Met SEM A2A1 A2A section at ~225° No plan A2A2 A2A section at ~170°-190° Axial cracks at ~180°, see Table 5-2 1
A2A3 A2A section at ~135° No plan A2A4 A2A section at ~240°-350° No plan A2A5 A2A section at ~90° Thin area of clad at 90° (met), see Table 5.3 1
A2A6 A2A section at ~350°-70° Axial crack at 10°;
circ. cracks at 20°-45°, see Table 5.4 through Table 5.10 4
4 (2 open cracks, 2 mounts)
A2A7 A2A section, contains exposed clad Clad cracks; undercut regions, see Tables 5.11 and 5.12 6
4 (2 open cracks, 2 mounts)
A2A8 A2A section, contains cavity nose No plan A2B Trimmed corner No plan
BWXT SERVICES, INC.
1140-025-02-24 100 Figure 5.1: Sectioning of Piece A2A (lower portion of cavity) showing new sample identifications.
A2A3 A2A5 A2A2 A2A1 A2A4 A2A6 A2A7 A2A8 A2B 180° 270° 90° 0°
BWXT SERVICES, INC.
1140-025-02-24 101 Table 5.2: Sample identification listing for Piece A2A2.
Piece ID Location Test Plan Met SEM A2A2A Upper portion of nozzle #3 bore No plan A2A2B1 Lower portion of nozzle #3 bore at ~190° No plan A2A2B2 Lower portion of nozzle #3 bore ~180° No plan A2A2B3 Contains axial cracks at ~180° in the J-groove weld.
Met sample through axial cracks 1
A2A2B4 Lower portion or nozzle #3 bore at ~170° No plan Figure 5.2: Sectioning of Piece A2A2, looking at the ID of the J-groove weld bore.
A2A2A A2A2B3 A2A2B2 A2A2B4 Mounted surface 180° 170° 190° A2A2B1
BWXT SERVICES, INC.
1140-025-02-24 102 Mounted Surface 90° 70° 100 Table 5.3: Sample identification listing for Piece A2A5.
Piece ID Location Test Plan Met SEM A2A5A RV head near 90° No plan A2A5B RV head clad near 90° No plan A2A5C Thin region of clad near 90° Met sample through thin region 1
A2A5D J-groove weld and clad near 90° No plan Figure 5.3: Piece A2A5 before sectioning. The mounted surface is indicated.
BWXT SERVICES, INC.
1140-025-02-24 103 Figure 5.3 (cont.): Piece A2A5 after sectioning, looking down on the front face of previous photo. The mounted surface on sample A2A5C is indicated. This area contained the thinnest measured cladding (0.202).
A2A5A A2A5D A2A5C A2A5B Mounted Surface of A2A5C
BWXT SERVICES, INC.
1140-025-02-24 104 0° Axial Crack at ~10° A2A6B A2A6A1 A2A6A2 Table 5.4: Sample identification listing for Piece A2A6.
Piece ID Location Test Plan Met SEM A2A6A1 RV head near 90° No plan A2A6A2 (see below)
Lower portion of J-groove weld and clad from 350°-70° Contains lower portion of axial crack at ~10° and circ cracks (0°-45°)
3 2
A2A6B (see below)
Upper portion of J-groove weld from 350°-70° Contains upper portion of axial crack at ~10° 1
2 Figure 5.4: Piece A2A6 was first sectioned into Pieces A2A6A and A2A6B. Piece A2A6A was further sectioned into Pieces A2A6A1 and A2A6A2. Both cuts were made on the same plane, parallel to the paper. The first cut line is partially visible; Piece A2A6B is the upper portion of the weld. The second cut line between Pieces A2A6A1 and A2A6A2 is obscured by Piece A2A6A1.
BWXT SERVICES, INC.
1140-025-02-24 105 Table 5.5: Sample identification listing for Piece A2A6B.
Piece ID Location Test Plan Met SEM A2A6B1 Upper portion of J-groove weld at ~350° No plan A2A6B2 Upper portion of J-groove weld axial crack at ~10° Lower surface mounted for met/SEM 1
1 A2A6B3 Mid portion of J-groove weld axial crack at ~10° Open crack SEM sample 1
A2A6B4 Upper portion of J-groove weld from 30°-70° No plan Figure 5.5: Piece A2A6B after sectioning. The bottom surface of A2A6B2 was mounted. The axial crack in A2A6B3 was opened up for SEM.
A2A6B4 A2A6B3 A2A6B2 A2A6B1
BWXT SERVICES, INC.
1140-025-02-24 106 Table 5.6: Sample identification listing for Piece A2A6A2.
Piece ID Location Test Plan Met SEM A2A6A2A Lower portion of J-groove weld and clad at ~70° No plan A2A6A2B Lower portion of J-groove weld and clad at ~45° Contains circ crack near 45° 1
A2A6A2C Lower portion of J-groove weld and clad at ~30° Open circ crack sample for SEM 1
A2A6A2D Lower portion of J-groove weld and clad at ~20° Contains circ crack near 20° 1
1 A2A6A2E Lower portion of J-groove weld and clad at ~10° Contains axial crack and circ cracks at 10° 1
A2A6AF Lower portion of J-groove weld and clad at ~0° No plan Figure 5.6: Piece A2A6A2 after sectioning. Additional sections were made on A2A6A2B, -C, -D, and -E. Refer to the following four tables and figures.
A2A6A2A A2A6A2F A2A6A2E A2A6A2D A2A6A2C A2A6A2B
BWXT SERVICES, INC.
1140-025-02-24 107 Table 5.7: Sample identification listing for Piece A2A6A2B.
Piece ID Location Test Plan Met SEM A2A6A2B1 Lower portion of J-groove weld at ~45° (includes bore)
No plan A2A6A2B2 Lower portion of J-groove weld and clad at ~45° Contains circ crack near 45° 1
A2A6A2B3 Clad at ~45° No plan Figure 5.7: Piece A2A6A2B after sectioning (side view of Figure 5.6).
The top surface of A2A6A2B2 was mounted.
-B1
-B2 (top surface mounted)
-B3 circ. crack in J-groove weld
BWXT SERVICES, INC.
1140-025-02-24 108 Table 5.8: Sample identification listing for Piece A2A6A2C.
Piece ID Location Test Plan Met SEM A2A6A2C1 Lower portion of J-groove weld and upper surface of clad at ~30° (includes bore)
No plan A2A6A2C2 Lower portion of J-groove weld and clad at ~30° Circ crack near 30° bent open for SEM 1
A2A6A2C3 Lower portion of J-groove weld (RCS side)
No plan Figure 5.8: Piece A2A6A2C after sectioning (side view of Figure 5.6). The circumferential cracks were bent open for SEM.
circ. cracks near 30°
-C1
-C2
-C3
BWXT SERVICES, INC.
1140-025-02-24 109 Table 5.9: Sample identification listing for Piece A2A6A2D.
Piece ID Location Test Plan Met SEM A2A6A2D1 Lower portion of J-groove weld at ~20° (includes bore)
No plan A2A6A2D2 Lower portion of J-groove weld and clad at ~20° Contains circ crack at ~20° 1
1 Figure 5.9: Section photo for Piece A2A6A2D (side view of Figure 5.6). The mounted surface of Piece A2A6A2D2 for optical and SEM examination is the lower surface (not visible) in the photo.
-D1
-D2 (Lower surface mounted) circ. crack at
~20°
BWXT SERVICES, INC.
1140-025-02-24 110
-E1 Lower surface mounted
-E3
-E2
-E1
-E4 circ. crack at
~10° axial crack at
~10° mounted surface Table 5.10: Sample identification listing for Piece A2A6A2E.
Piece ID Location Test Plan Met SEM A2A6A2E1 Lower portion of J-groove weld at ~10° Lower surface mounted for met 1
A2A6A2E2 Contains clad at ~20° No plan A2A6A2E3 Contains clad at ~0° No plan A2A6A2E4 Lower portion of J-groove weld (RCS side)
Contains axial and circ cracks at ~10° (PNL Sample)
Figure 5.10: Section photo for Piece A2A6A2E (side view of Figure 5.6).
The mounted surface of Piece A2A6A2E1 is indicated. Piece A2A6A2E4 is reserved for PNL.
BWXT SERVICES, INC.
1140-025-02-24 111 Table 5.11: Sample identification listing for Piece A2A7.
Piece ID Location Test Plan Met SEM A2A7A RV head and clad near 350° No plan A2A7B RV head and clad near 340° No plan A2A7C RV head near 345° No plan A2A7D Undercut region near 345° Met mount 1
A2A7E RV head and clad near nose No plan A2A7F Undercut region near nose Met mount 1
A2A7G RV head near nose No plan A2A7H Clad prior to nose No plan A2A7I RV head and clad near 50° No plan A2A7J RV head and clad near 40° No plan A2A7K Undercut region near 40° Met mount 1
A2A7L Center portion of clad cracks SEM open crack sample 1
A2A7M Adjacent to center cracks Met mount (center portion) 1 1
A2A7N Clad cracks toward 270° Met mount (270°)
1 1
A2A7O Clad near 0° No plan A2A7P Center portion of clad cracks Reserved for PNL A2A7Q Clad near 40° No plan A2A7R Clad near 40° No plan A2A7S Clad cracks toward 90° Met mount 1
1 A2A7T Clad near 60° No plan A2A7U Clad near 10° No plan
BWXT SERVICES, INC.
1140-025-02-24 112 Figure 5.11: Section photo for Piece A2A7. The mounted surfaces for the -D, -F, -K,
-M, -N, and -S samples are indicated by the white arrows. Further sectioning of Piece A2A7L is shown in Figure 5.12.
A B
C D
E F
G H
I J
K L
M N
O P
Q R
S T
U
BWXT SERVICES, INC.
1140-025-02-24 113 Table 5.12: Sample identification listing for Piece A2A7L.
Piece ID Location Test Plan Met SEM A2A7L1A Center portion of clad cracks SEM open crack sample 1
A2A7L1B Adjacent to center cracks No plan A2A7L2A Center portion of clad cracks SEM open crack sample 1
A2A7L2B Adjacent to center cracks No plan Figure 5.12: Section photo for Piece A2A7L. The main crack located near the center of A2A7L was opened in the laboratory, resulting in Pieces A2A7L1 and A2A7L2.
Additional sections, which created the -A and -B pieces, were made to facilitate the SEM examinations. The surfaces examined by SEM are indicated.
-L1A
-L1B
-L2A
-L2B Cavity nose Looking down at the corrosion exposed cladding surface CRDM nozzle 3 Crack opened up and examined by SEM
BWXT SERVICES, INC.
1140-025-02-24 114 Table 5.13: Sample identifications for Piece A1.
Piece ID Location Test Plan Met SEM A1A Contains cavity nose No plan A1B Contains cavity side wall toward 90° Met and SEM/EDS samples (see Table 5.14) 2 1
A1C Contains nozzle #3 bore and small portion of cavity No plan A1D Contains cavity side wall toward 270° Met and SEM/EDS samples (see Tables 5.15 and 5.16) 2 1
Figure 5.13: Sectioning of Piece A1 into four pieces. Pieces A1B and A1D were further sectioned for metallography and SEM. Refer to Figure 5.14 through Figure 5.16.
270° A1A A1B A1C 0° 90° 180° A1D
BWXT SERVICES, INC.
1140-025-02-24 115 A1B7 A1B1 A1B6 A1B4 A1B3 A1B2 A1B5 is hidden below Mounted face Mounted face Table 5.14: Sample identifications for Piece A1B.
Piece ID Location Test Plan Met SEM A1B1 Upper portion of cavity side wall near 90° No plan A1B2 Upper portion of cavity side wall near 90° Transverse met mount 1
A1B3 Middle portion of cavity side wall near 90° SEM/EDS sample 1
A1B4 Lower portion of cavity side wall near 90° Transverse met mount 1
A1B5 RV head behind cavity side wall No plan A1B6 Lower portion of cavity side wall near 90° No plan A1B7 Cavity side wall No plan Figure 5.14: Section photo for Piece A1B, looking at the cavity side wall. The mounted surfaces of Piece A1B2 and Piece A1B4 is indicated.
BWXT SERVICES, INC.
1140-025-02-24 116 Table 5.15: Sample identifications for Piece A1D.
Piece ID Location Test Plan Met SEM A1D1 Cavity side wall near 270° No plan A1D2A Upper portion of cavity side wall near 270° No plan A1D2B Upper portion of cavity side wall near 270° Transverse met mount location 1
A1D2C Middle portion of cavity near 270° SEM/EDS 1
A1D2D Lower portion of cavity side wall near 270° Transverse met mount location 1
A1D2E RV head behind cavity side wall Macroetch sample A1D2F Lower portion of cavity near 270° No plan Figure 5.15: Section photo for Piece A1D, looking at the cavity side wall. Refer to Figure 5.16 for the mounted surface locations.
A1D1 A1D2A A1D2E Macro etch sample (hidden below)
A1D2B A1D2C A1D2D A1D2F
BWXT SERVICES, INC.
1140-025-02-24 117 Table 5.16: Sample identifications for Piece A1D2B and Piece A1D2D.
Piece ID Location Test Plan Met SEM A1D2B1 Upper portion of cavity side wall near 270° Transverse met mount location 1
A1D2B2 Upper portion of cavity side wall near 270° No plan A1D2D1 Lower portion of cavity side wall near 270° Transverse met mount location 1
A1D2D2 Lower portion of cavity side wall near 270° No plan Figure 5.16: Section photo for Pieces A1D2B and A1D2D, looking at the cavity side wall. The mounted faces for Piece A1D2B1 and Piece A1D2D1 are indicated.
A1D2B1 A1D2D1 A1D2B2 A1D2D2 Mounted surface Mounted surface
BWXT SERVICES, INC.
1140-025-02-24 118 Sample A2A7M Knoop Microhardness 0.0 50.0 100.0 150.0 200.0 250.0 300.0 350.0 0.000 0.050 0.100 0.150 0.200 0.250 0.300 Distance from Upper Clad Surface, inches Microhardness, HK Figure 6.1.1.1: 4X macro photograph of metallurgical mount A2A7M. Refer to Figure 5.11 for the sample orientation. Cladding thickness ranged from 0.227" to 0.277" (5.77 to 7.04 mm). Knoop microhardness values exhibited a hardness elevation near the exposed cladding surface.
RCS side (underside of cladding)
Exposed cladding surface In-service cracking Microhardness traverse
BWXT SERVICES, INC.
1140-025-02-24 119 Etched 100X Etched 375X Figure 6.1.1.2: Micrographs showing intergranular attack (IGA) and intergranular or interdendritic cracking on the exposed stainless steel cladding.
BWXT SERVICES, INC.
1140-025-02-24 120 As-polished 48X Etched 48X Figure 6.1.1.3: Micrographs showing the deepest crack observed in A2A7M.
Fine intergranular or interdendritic cracks emanating from the crack tip are visible. The crack tip is estimated to be approximately 0.057" (1.47 mm) below the surface. The cracks in the above two photos are the same, but are shown at slightly different planes due to re-polishing.
BWXT SERVICES, INC.
1140-025-02-24 121 100X 375X Figure 6.1.1.4: Typical clad microstructure in the mid-thickness of the cladding.