ML20217A837
ML20217A837 | |
Person / Time | |
---|---|
Site: | San Onofre |
Issue date: | 04/27/1997 |
From: | ABB COMBUSTION ENGINEERING NUCLEAR FUEL (FORMERLY |
To: | |
Shared Package | |
ML20046D781 | List: |
References | |
96-OSW-003-NP, 96-OSW-003-NP-R00, 96-OSW-3-NP, 96-OSW-3-NP-R, NUDOCS 9709230007 | |
Download: ML20217A837 (26) | |
Text
.
Aill) Combustion Engineering Nuclear Operations Field Senices l
Report Number 96-OSW 003-NP Rev.00 l
EPRI Steam Generator Examination Guidelines Appendia il Qualification for Eddy Current Plus Point Probe Examination of Allit CE Weided Sleeves April 27,1996 Pmpend By -
bk b
ny Date:
4 /?~1/46 Of
.aw D.. v47/u Appa Br Apprmed By -
'bN 80 - %
Date ?
e Manager, Field Sen ces 7% D D eze.22 e,,,e
,e PDR ADOCK 05000361 P
TAul.E OF CONTENTS Sislis EEE 1.0
!ntroduction i
2.0 References 1
3.0 Sleeved Tube Flaw Types and Scope of Applicability 2
4.0 Sample Matrix 3
5.0 Data Acquisition 12 6.0 Data Analysis 14 7.0 Conclusions and Reconunendations 18 Attachment i Acquisition Technique Specification (ACTS) 19 Analysis Technique Specification ( ANTS) 20 Appendix A Drawmgs of EDM Sleeve Samples and ECT Printouts Appendix B ECT Printouts of Welded Sleeve Samples
.j.
EPRI Steam Generator Esamination Guldelines Appendis il Qualification for Eddy Current PluePoint Probe Esamination of Ailll CE Welded $1resci 1.0 Introduction The use of the + point cddy current probe in the field has shown it to be the best general purpose probe for slecte inspections. Its perfonnance has surpassed other RPC coils for detection of flaws in the presence of geometric indications. The objective is to qualify and document the + point probe l
to EPRI Appendix 11 Guidelines for the known damage mechanisms that have occurred m ABB CE l
welded sleeves. To date, the weld conditions that have been identified are process induced: sleeve blow holes in the weld; ucid suckback on the sleeve OD surface; inclusions in the weld; and lack-of fusion. The lack-of fusion condition cannot generally be found with ET and is therefore a condition that is tested for with UT. Ilot tears / cracking and shrinkage cracks have never been seen in ABB CE welded sleeves. This is because the heat input and cooling rate is sufficiently different from other welding processes to avoid this type of defect. In hundreds of welds metallographically examined over the last ten y ears no occurrence of hot or shrinkage cracking has ever been found.
His report documents the qualification effort for eddy current examination of ABB CE welded sleeves using the plus point probe. Included is a complete description of the samples used in the datasets for each of the flaw categories. This report also documents the results of the analyst peer review of the data. An Acquisition Technique Specification (ACTS)is attached which defines the acceptable equipment and technique variables for acquiring data. Also attached is the Analysis Technique Specification (ANTS) which defines the proper calibration, analysis parameters and reporting requirements.
2.0 References 2.1 " Verification of the Structural Integnty of the ABB CENO Steam Generator Welded Sleeve,"
CEN 628 P, Rev. 00 P, March 1996.
2.2 "PWR Steam Generator Exar.:ination Guidelines. Rev 5," Appendix 11. "Perfonnance l
Demonstration for Eddy Current Examinations." EPRI. October 1995.
I
.i.
3.0 Sleeved Tube riaw T pes and Scope of Applicability 3
31 Sleeve Raw Types Based on Geld experience of sleeve installation and operational experience of the in service slectes, the known damage mechanisms can be categorized As mentioned, all known damage mechanisms occur during the installation process and there have been no cases of Daws occurring durmg operation. His quahfication is to demonstrate rehable dctccnon for the following Daw conditions:
31.1 Blow Holcs. This is a volumetric ID condition caused by a build up of pressure in the annulus between the tube and the sleeve due to residual water, oxide or other volatile contamim tion. Blow holes can also result from the pressure built up as a result of the expansion of the heated air in the annulus. In this case, the existence of an excessive gap or increased secondary side heat sink conditions prevent thermal transfer to the tube and results in the heat being used to melt more of the sleeve. ne un supported molten metal is then subject to expulsion toward the sleeve ID creating a hole through the slecte wall. Since the tube wall does not experience melting at the blow hole location, there is no parent tube wall thinning associated with this condition This hu been confirmed by laboratory analysis of many blow holes. Ulow holes are a rejectable indication only if they occur below the weld center line. Blow holes occurring above the weld center line are not considered to be in the pressure boundary and is therefore an acceptable condition as long as weld integrity below the blow hole is confmned with UT.
3.1.2 li'cid /nclusmns. His is a volumetric sub surface condition associated with madequate tube cleanmg prior to weldmg. During welding, contaminants coalesce intemally in the weld and fonn oxide inclusions. His is a widely observed condition that, in most cases, is minor and not detrimental to weld integrity. In the most severe cases, inclusions can start at either the top or bottom of the weld from the sleeve tube annulus and proceed in a non linear path toward the interior of the weld. Weld inclusions have been observed only in the sleeve portion of the weld and not in the tube. His is consistent with the solidi 6 cation process of the molten metal.
3.1.3 S/ccvc OD Suckback his condition occurs on the sleeve OD and is a result of molten sleeve metal being pushed by gas pressure m the tube sleen anutus. If sufficient pressure develops, possibly coupled with weld sag, a blow hole can occur. Suckback can occur at the upper or lower edge of the voeld and only in the sleeve OD. In an axial cross section suckback femis with semi-circular geometry and can be local (hemispherical) or clongated in the circumferential direction. Inadequate cleaning can leave behind volatile contamination that can cause this condition.
3.1.4 l.ack offusion This occurs as a planar type ofinclusion occurring at the tube and sleeve faying surfaces. Two different types have been observed: (1) association with refractory oxides in the weld nugget creating laminar, non linear inclusions and (2) the indi enous oxide layer on the 3t tube surface prevents wetting of the joint faying surfaces during the weiding and blocks coalescence. It is discussed here for informational purposes only. Since. in most cases, ET cannot detect this condition, it is not an included Gaw type for Appendix H qualification.
2-
3.1.5 Primary andSecondary Ssde SCC Tius type of flaw could occur at a location where defonnation has left residual stresses eventually leading to corrosion cracking. Espansion transitions are potentially susceptible to this Oaw mechanism Although there have been no cases of SCC or other service mduced flaws in the sleeve pressure boundary, it is prudent to des etop and quahfy inspection methods for detectmg critical Oaws should they ever occur. The emphasis is to demonstrate detection of crack hke Gaws of dimensions substantially below the maximum allowable to withstand postulated worst case scenarios EDM notches are used to simulate SCC (kws located in the pressure boundary at the espansion transitions, sleeve and parent tube The placement of the notches was chosen to replicate the most difficult sites for detection. Equal emphasis is placd on both circumferential and asial onentstions as well as ID s ersus OD.
3.1.6 P/tting As described above with regard to SCC, it is possible that pitting could occur at some point in the future. Ilowever, this flaw t>pe is not currently considered as part of the qualification Even though pittmg is not included for quahfication. the ASME machined Oaws demonstrate sensitivity to volumetric type flaws in both the slees e and parent tube.
3.2 Scope ofApphcabshty The limits of the techniques qualified and documented in this report are specifically defined as follows:
Cddy current plus point probe inspection of the entire pressure boundary of the tube and sleeve region. The axial extent of this region is from the low er expansion transition m the sleeve to the top end of the sleeve and includes the weld. The qualification is for accept / reject only for circumferential and axial SCC in the tube / sleeve pressure boundary. This qualification is also for accept / reject only for the known w cid defects escluding lack-of fusion and pitting. The weld flaw categories that this qualification applies to are (1) volumetric ID surface Caws (blow holes) and (2) sub surface volumetric flaws (inclusions and sleeve OD suckback).
4.0 Sample Alstrix 4.1 Spectfic Flaw Typesfor the Matrox ofSamples Appendix 11 recogmzes 6 S/G tube Oaw mechanisms:
- 1. Thinning
- 4. IGA / SCC
- 2. Pitting
- 5. Primary side SCC
- 3. Wear
- 6. Impmgement Damage flowever, since none of these fl2w types have ever been found in existing ABB CE sleeves, this qualification effort addresses known weld zone flaw conditions The Oaw types included for the qualification effort are blow holes, inclusions and suckback. Lack-of fusion is not a condition that 3
- 4. l Specific Raw Typesfor the Matnt ofSn uples (cont 'd; can be reliably found with eddy current testing and is therefore not included in the Oaw mattn.
Primary and secondary side SCC is included to demonstrate detectability of critical flaws within the pressure boundary. Circumferential and axial EDM notches were machined into the sample sleeves at criticallocations in the pressure boundary to simulate SCC flaws. He sample matrix has a mininium of 16 flaws for each damage mechanism as required by Appendix 11. A single fleeve configuration was chosen and fabricated to represent the pressure boundaries for each of the different sleeves. He ABB CE sleen., are for both 3/4"and 7/8" tubing. The EDM notches wcre machined into 3/4" tube sleeves [
- l. De 3/4" tube samples were both.042" and
.04H" wall representing the ABB CE and Westinghouse tubes respectively. He 3/4" qualification can be applied to 7/8" tube sleeves by making the appropriate adjustments in frequency and fill-factor, ne frequency adjustment is to compensate for changes in wall depth sensitivity when transitioning from the [
] wall thickness for the 3/4" slectc to the [
] wall thickness for the 7/8" sleeve. He samples were welded at one end and rolled at the other end ne samples were l
also heat-treated to represent the as installed condition The pressure boundary and joints for the l
three different sleeve types were replicated using a single configuration. ne three sleeve types are as follows:
- 1. Straight Sleeve for Full Tube Sheet Length
- 2. Short Length Sleeve for Top-of Tubesheet Roll Transition
- 3. Tube Support Sleeve in addition to the fabricated EDM tubc/ sleeve assemblics, several weld joints are includes m the flaw matrix. The weld :amples are from a combination of Prairic l> land pulled tubes and laboratory produced samples of both 3/4" and 7/8" tubc/ sleeve configurations. Figure 4.1.1 shows the S/G as installed sleese configuration.
4
4.1 Specspc Raw 1)pcsp>r the Afatrix ofSamples (cont 'd)
Figure 4.1.1. ETZ/RTZ Sleeve Configuration 4.2 TubetSleeve Presstore Bostndary Detection Data Set SCC Flaus According to Appendix 11. a technique that is qualified to size Daws requires a minimum of 16 samples,2/3 of which (lI of the 16 samples) are specified to have Daws 260% 1W evenly distributed over the range. The remaining Daws are spt cified to be in the range of 20% to 59%
'hV. The data set is not required to include unaawed samples. If however, it is desired to have a technique that is " accept / reject" qualified only, then all of the Daws are specified to must be 260%
EV. This would require a minimum of 16 samples to achieve an 80% POD with 90% confidence.
5
4.2 Tube Sleeve Prenure Bosmdary I)ctcction IMta Set SCC Rsns s (cont u)
As stated abme, the data set does not have to include unflawed samples. He flaw types for this qualification fall into the acc r/>t rc)cci category. Four tube / sleeve samples were fabricated for this qualification effort to simulate SCC flaws in the critical locations of the pressure boundary, particularly in the expansion transitions. Each of the machined flaws are [ ] length x [
] width and are nominally [ ] % DV in both circumferential and axial orientations. His exceeds the Appendix 11 requirement of all Oaws to be 260% BY. The goal is to demonstrate 80% POD with 90% confidence for all flaws 2[ j% DV within the pressure boundary. Table 4.2.1 lists the EDh1 flaws in the samples Drawings of the samples, machining inspection reports and ECT printouts can be found in Appendix A of this report.
Tube / Sleeve Notch #
Locatien/ Orientation As Iluilt % TW 42T 2 /174 5 1
tube ID at siv end top / axial
[]
2 tube ID at upper hydr expan trans / axial
[]
3 sleeve OD in lower hydr expan trans / axial
[]
4 sleeve OD in mid span / axial
[]
sleete OD in upper roll expan trans / axial
[]
42T 5 /167-3 1
tube ID at :, v end top / cire
[]
2 tube ID at upper hydr expan trans / cire
[]
3 sleeve OD in lower hydr expan trans / cire
[]
4 sleeve OD in mid span / circ
[]
5 sleeve OD in upper roll expan trans / circ
[]
48T 2 / 200 2 1
tube ID at sly end top / cire
[]
2 tube ID at upper hydr expan trans / cite
[]
3 sleeve OD in lower hydr expan trans / cire
[]
4 sleeve OD in mid span / cire
[]
[]
6 sleeve OD in upper roll expan trans / circ
[]
48T-4 / 263 3 1
tube ID at sly end top / axial 40 2
tube ID at upper hydr expan trans / axial 41 3
sleeve OD in lower hydr expan trans / axial 40 4
sleeve OD in mid span / axial 41 5
sleeve OD in upper roll expan trans / axial 41 Table 4.2.1 Tube / Sleeve EDh1 Flaws 6
4.3 Il'cht Dctcctton thria Set Blow lloles, inclustom and li'cid Suc khack Several laboratory sample welds were fabricated to simulate the worst case conditions that can be experienced in the Geld that result in poor welds. The samples were then eddy current and ultrasonically tested pnor to confinnatory destructne exams. As discussed earlier, the only Daws that have occurred are blow holes, inclusions and weld suckback. By varying parameters, the Dawed samples represented a wide range of severity with the goal of detenmning the NDE detection capabilities in addition to the laboratory welds, several pulled sleese welds were also included in the detection data set. Table 4.3.1 shows the complete data set includmg the EDM notch samples. For the purposes of this quali0 cation, the detection categories for the welds are: (1) surface flaws such as blow holes, and (2) sub surface Daws which include both inclusions and suckback. Table 4.3.2 shows the destructive examination and metallography results of the welds.
ECT printouts of the welded sleeve samples can be found in Appendix B of this report.
7
pie IAetalurgy Data E(TT DATA Ccyments g
.,3 uen Sample Type indication Category Lac.
Detect. CA. Loc.
1 OS-2 LAB SB SUB Y'
2 OS3 LAB BH SFC Y
l 3
OS.10 LAB SB SUB
+
N
+
29% SB on + side l
4 OS 14 LAB SB SUB Y
l 5
OS.24 LAB SB SUB Y'
6 CS 5 LAB BH SFC
+
Y
+
7 JS 13 LAB SB SUB
+ /.
Y 8
+ /.
Y
]
9 0T.1 LAB SB/ICL SUB
+ /-
Y' l
10 OT 2 LAB BH SFC Y
l 11 OT.3 LAB ICL SUB
+ /.
Y' l
12 OT 5 LAB SB/lCL SUB
+ /.
Y l
13 OT.12 LAB SB/lLL SUB
+ /.
Y l
14 OT.16 LAB BH SFC Y
l 15 OT.17 LAB ICL SUB
+ /.
Y l
l 16 OT.20 LAB ICL SUB
+/.
Y' j
i 17 OT 21 LAB SB/ICL SUB
+ /.
Y' l
18 OT 23 LAB ICL SUB across Y
l 19 OT.24 LAB ICL SUB
+ /.
Y 20 O T-31 LAB SBILOF SUB across Y
21 11/20 FIELD BH SFC
+
Y
+
22 17G0 FIELD BH SFC
+
Y
+
l 23 7/22 FIELD BH SFC
+
Y
+
l 24 11r22 FIELD BH SFC
+
Y
+
l 25 6/23 FIELD BH SFC
+
Y
+
BH on + side l
26 9/25 FIELD BH SFC
+
Y
+
l 27 10/27 FIELD BH SFC across Y
l 28 13/27 FIELD BH SFC
+
Y
+
BH on + side l
29 1931 FIELD BH SFC
+
Y
+
l 30 29/J1 FIELD BH SFC
+
Y l
31 8/34 FIELD BH SFC
+
Y 00 l
32 14/34 FIELD BH SFC
+
Y l
33 12/71 FIELD BH SFC
+
Y
+
j 34 2/47 FIELD BH SFC
+
Y
+
BH on + side l
35 935 FIELD BH SFC
+
Y l
36 6/25 FIELD BH SFC
+
Y
+
BH on + side l
37 6/29 FIELD BH SFC
+
Y 00 l
38 6GS FIELD BH SFC Y
l 39 700 FIELD BH SFC
+
Y
+
l 40 7/46 FIELD BH SFC
+
Y
+
l 41 9/25 FIELD BH SFC
+
Y
+
BH on + side l
42 1U52 FIELO BH SFC
+
Y
+
l 43 1
LAB NOTCH SUB
+0 $
Y 0.5 l
44 1
LAB NOTCH SUB
-0.5 Y
05 l
45 1
LAB NOTCH SUB 3.3 Y
-63 l
46 1
LAB NOTCH SUB 11.3 Y'
11.3
[
47 2
LAB NOTCH SUB
+0 5 Y'
O.5 sa.nple f.2 noisy, use l
48 2
LAB NOTCH SUB
-0.5 Y
-0.5 cire. ave filter or scroll l 49 2
LAB NOTCH SUB
-63 Y
63 data l
50 2
LAB NOTCH SUB 11.3 Y'
11.3 l
51 3
LAB NOTCH SUB
+0 5 Y
05 l
52 3
LAB NOTCH SUB
-05 Y
-0.5 l
53 3
LAB NOTCH SUB 63 Y
-63 l
55 4
LAB NOTCH SUB
+ 0 5. _
Y 05 56 4
LAB NOTCH SUB
-05 Y
05
~
57 4
LAB NOTCH SUB 13 Y
13 68 4
LAB NOTCH SUB 63 Y
-6 3 59 4
LAB NOTCH SUB 11 3 Y
11 3 60 2N2B LA3 SD SUD
+
Y
+
Pre-pro sample 61 13A/13B LAB BH SFC
+
Y Pre pro Sample 62 5/48 FIELD SB/ICL SUB Y
63 9/57 FIELD SE1/ICL SUB Y
64 7/52 FIELD SB/ICL SUB Y
65 7/63 FIELD SB/ICL SUB Y
66 5/74 FIELD 50/ICL SUB Y
i l
l Tab;c 4 3.1 - Welded Sleeve Samples Detection Data Set 9
INCLUSION SUCKBACK SAMPLE AZIMUTHAL WELD LIGAMENT RADIAL RADlAL AXIAL OTHER STATUS NUMBER LOCATION HEIGHT HEIGHT
%TW HEIGHT
% TW LOCTN 7/8" UNCLEANED TUDES OS.2 170 0 100 0 100 0%
0 000 0% i
{ DLW 350 0.112 0.112 0%
0 026 61%
360 0 100 0 100 0%
0 000 0%.
OS. 3 30 0 082 0 076 0%
0 020 18 %
DLW 210 0.092 0 000 0%
0 014 9%
DLW
~
7 100 %
DLOW HOLE OS to 85 0 056 0 055 l
0%
j 0 000 j 0% j j
t 265 0 128 0 128 l
0%
1 0 018 1 29% ! ABV l
I OS 14 85 0 078 0 070 0%
0 030 1 31 %
DLW l
[
265 0 042 0 042 0%
0 000 1 0%.
I i
OS 24 15 0.112 0.112 l
0%
0018 32% i BLW 195 0 092 0 092 1
0%
0 000 0% I OS 25 160 0.100 0 100 j
0%
0 000 i 0%
['
340 0 000 0%
0 000 1 0%
i OS.28 150 0 084 0 064 0%
0 000 j 0% i
[
330 0 100 0 100 I 0%
0 000 1
0% I I.
OS. 38 0 10 0 000 0 000 0%
l 0 000 j 0% l LACK of FUSION 360 0 000 0 000 1
0%
1 0 000
- C% I LACK of FUSION
^
OS. 40 90 0 000 0 000 i
0%
j 0000 j 0% j 270 0 100 0 040 1
0%
J 0000 1 0% 1
~~
OS.45 100 0 000 0 000 0%
0 000 0%
CS-4 1
1/5 0.162 0 162 0%
j 0000 1 0%
l
}
i I
355 0 176 0 176 I
0%
I C 000 I 0% i i
I CS. 5 5
0 180 0 180 35%
0 000 0%
BLW 185 0.176 0.164 0%
0 000 0%
345 100 %
ABV BLOW HOLE
"~
CS 13 90 0 138 0138 0%
1 0.015 g 22% l ABV DLW l 270 0 163 0 163 I
0%
I 0000
- 0% i 1
CS 22 5
0.143 0 143 0%
0020 32% j DLW ABV i 10 0%
0 020 58% !
BLW j 3/4"
^
185 0 155 0 155 0%
0 000 0% l 1
UNCLEANED TUBES OT 1 0
0.152 0 ISC 10 % 5 %
0 0%
AUV DLW
~
80 0 228 0 208 43%
0 0%
BLW
~~
90 0.236 0 124 26 % 71 %
0 0%
ADV.0LW 170 0 240 0.192 31 %
0 0%
DLW 180 0 238 0 192 0%:74%
0 0%
ABV.BLW 260 0 211 0 175 0% 0%
0 0%
ABVDLW 270 0.212 0.172 0% 0%
0 0%
ADV DLW 350 0 158 0 112 12 % 39 %
0 0%
ABV BLW OT 2 100 %
DLW BLOW HOLE OT. 3 j
145 0.124 0 082 j
79%
1 0
j 0% i BLW I
325 0 080 0 028 1 14 % 23 % 1 0
1 0% !ABVBLW OT 5 50 0 120 0 052 7%:24%
0 0%
ABV.BLW INTE RMIT INCLUS.
60 0.112 0 072 32 %
0 0%
OLW INTERMIT INCLUS.
140 0.118 0 054 0%:15%
0 0%
ABV t't.W 150 0 124 0 060 0 % 38 %
0 028 37 %
ABV 0LW 230 0.102 0 032 26 % 31 %
0 0%
ABV.DLW 240 0 116 0 050 19 %:18 %
0 0%
ABV.DLW 320 0 080 0 000 0%:0%
0 0%
ABV.DLW INTERMIT INCLUS.
330 0 064 0 000 0%'0%
0 0%
ABV BLW I OT. 12 0
0 136 0 102 6% 9%
0 014
! 9%
ABVBLWj 10 l 0 120 0 102 i
30 %
0 039 l 89%
ABV s
s
180 0.127 0 049 0 % 12%
0 0%
ABV BLW 190 0 082 0 007 0%0%
0 1 0%
ABV BLW 270 0 066 0 006 0%0%
0 l 0%
ABVBLW,
250 0 066 0 014 0% 0% !
O i 0%
ABVBLW i OT. 16 0 084 i
l 100%
l BLW BLOW HOLE OT. 17 i
90 0 112 0 096 16%
1 0
i 0% i ABV j
i 270 0158 0 094 I 35 % 40 % !
O i 0% !ABVBLW '
OT. 20 j
70 0 128 0 076 1 38 % 29 % ]
O 1 0%
l ABVBLW IABV BLW l i
250 0134 0 0G8 I 65 % 40 % 1 0
1 0%
OT. 21 135 0 112 0 100 19%
0 026 15%
BLW 315 0 085 0 057 14%
0 0%
ABV 135 145
<0035 36 %
OT. 24 l
135 0 212 0 182 55% 17% !
0 l 0% i ABV BLW {
s l
315 0174 0 078
! 66 % 97% I C
1 0% IABVBLW I OT. 31 90 0 178 0 000 0%
l 0012 l
j l 35% l LOF j LACK of f USION 270 0 220 0 000 0%
0005 30%.
LOF
. TACK of FU$lON 3/4 CLEAN j i
TUBES i
1 C1 1 i
A 0 200 0 200 l
0%
i 0 000 0% _l 6
i B
0 170 0 170 1
0%
I 0 000 l 0%.
I CT. 2 A
0.226 0 226 l
0%
0 000 l 0% :
0% l j
B 0176 0 176 0%
0 000 i
CT. 3 A
0.178 0 178 0%
0 000 0%
i 0
0188 0 188 0%
0 000 0%
I CT. 4 A
0218 0 218 0%
0 000 0%
l B
0168 0168 0%
0 000 0%
CT.5 A
0194 0.194 0%
0 000 0%
j B
0 228 0 ??*
0%
0 000 0%
i CT. 6 A
0232 0.232 0%
0 000 0%
j B
0172 0 172 0%
0 000 0%
CT. 30 130 0 165 0165 0%
0 000 0%
l 31 0 0125 0125 0%
0 000 0%
i CT. 31 120 0.144 0 144 0%
0 000 0%
1 300 0155 0155 0%
0 000 0%
I CT. 35 110 0 149 0149 0%
0 000 0%
i 290 0184 0M 0%
0 000 0%
CT. 36 A
0150 0 150 0%
0 000 0%
C T. 38 A
Or5 0175 0%
0 000 0%
[
CT. 39 A
0 158 0158 0%
0 000 0%
l C T. 41 80 0 146 0146 0%
0 000 0%
260 0 182 0 182 0%
0 000 0%
CT. 42 60 0188 0188 0%
0 000 0%
}
240 0 178 0 178 0%
0 000 0%
CT. 45 A
0.184 0.184 0%
0 000 0%
{
CT. 46 90 0.168 0168 0%
0 000 0%
j 270 0180 0180 0%
0 000 0%
i CT. 47 90 0180 0.180 0%
0 000 0%
l 270 0 239 0239 0%
0 000 0%
CT. 48 30 0 160 0.160 0%
0 000 0%
j 210 0 153 0 153 0%
0 000 0%
Table 4.3.2. Welded Sleeve Samples Destructive Eumination Results 11
5.0 Data Acquisition Attachment I is an Acquisition Technique Specification (ACTS) that was prepared for acquisition of the sleeve data. He required elements for the ACTS are listed in Appendix H Section 2. He acquisition must be done according to the ACTS procedure for both the qualification effort and field examinations.
5.1 hohe Desenptwn Since its introduction in 1995, the plus point probe has become recognized as the best general purpose probe for examining sleeves and the top of the tubesheet region of steam generator tubing.
It can also be used to inspect other regions as well. Other probes can be used to supplement the inspection, such as 3-coil MRPC. nc + point probe has unique characteristics for noise suppression as a result of the 90' opposing windings configured in the shape of a plus point. The axial and circumferential windings provide sensitivity to both circumferential and axial flaws (respectively). The axial winding has a response that is 180' out of phase from the circumferential windings. As a result, the coil acts as a differential coil to suppress the efTects of geometry and the support structure. It has a major advantage over a standard differential coil by providing equal sensitivity to both axial and circumferential flawe while suppressing geometric signals.
He coil is wound for a resonant frequency of approximately 100 to 120 Litz. He low resonant frequency is to achieve the best sensitivity to parent tube flaws within the pressure boundary. Here are several configurations for a plus point probe. It can be combined with other coils by using a 2 or 3-coil probe housing. The + point coil is placed in one of the slots with other coils such as a pancake coil or coils wound to different resonance frequencies occupying the other coil slots. In RPC acquisition, each revolution is marked with a trigger pulse ne axial translation of the probe through the SG tube is done by the probe pusher. The result of the simultaneous rotation and axial translation is a helical scan of the tube with a pitch of about 0 025" per revolution. All calibration standard data and inspection data must be taken at the same rotational and axial speeds. Figure 5.1.1 shows a single plus point probe configuration COL 9E A$ C4 AS$Y AMfCUL ATO4 gy*
YnE.ta s
^5v wcowv CC1. SKE
+ PolNT '* M E R Coll ch%
.wge Figure 5.1.1 - Single Plus Point Probe Coil Configuration 12-
5.2 Acquositwn Frequenctes and Apphcatwns he acquisition frequencies are [
] Lilz. Considenng the range of sleeve wall thickness of between [
] and the tube wall thickness range of 0.043" to 0.050", there is a total material thickness between [
). %c skin depths in inconel 600 or 690 are:
Freauenes tklin I skin Denth (mi!O 50 86 75 70 100 61 150 50 300 35 400 31 One skin depth is the distance or depth into the material where the eddy current density has dropped by a factor of 1/c or 37% of the surface eddy current density. For maximum sensitivity, it is generally desired to test a material with frequencies that do not exceed 2 skin depths. Although lower frequencies have better sensitivity over the range of material thickness. there is a trade offin l
phase response. A higher frequency ([
] Litz) can be used to distinguish parent tube from l
sleeve indications due to the increased phae response and reduction in sensitivity to parent tube indications.
5.2.1 [
]
his is the test frequency for distinguishing between parent tube from sleeve indications. His frequency has good sensitivity through the thickness of the sleev, and poor sensitivity to the parent tube. Its main advantage is s ery good phase separation for separating sleeve from tube indications. It is also not overwhelmingly affected by deposits on the OD of the tube.
5.2.2 [
]
This is a secondary frequency for detection and can be used as a mixing charmel.
His frequency is also useful for sleeve versus tube signal confinnation.
5.2.3 [
] - his is the primary inspection frequency for evaluation of all regions of the sleeve pressure boundary including the weld and parent tube. His frequency can also be used as a mixing channel.
52.4 [
] - This frequency is used for locating the weld centerline and support structure, and for confirming parent tube indications. It can also be used as a mixing channel.
13
6.0 Data Analysis is an Analy sis Technique Specification ( ANTS) which specifies the required settings for analyzing the acquired data set. Analy sis must be done according to the ANTS procedure. He ANTS is prepared in advance for use with the anal)st peer review part of the quahfication effort The peer review is to be done and documented in accordance with Appendix 0 guidehnes 6.1 Cahbration 6.1.1 Rotation Sctrings Rotate the Lissajous displa)s for each raw channel [
] so that the 100% DV AShiE sleeve flaw is positive s emcal and to the left Note that axial flaws will have a response going in the positisc vertical direction and to the left.
Rotate the displays for Pl [
] and P2 [
] so that the 100% TW AShiE slecte flaw is set to negative vertical and to the right Note that circumferential flaws will have a response going in the negative vertical direction and to the right Rotate the trigger channel to gisc a positise pulse for every 360 rotation.
6 l.2 S[un Scitings - For the [
] Lliz. PI [
], and P2 [
] channels. locate and isolate the largest amplitude response to the 100% DV AShiE flaw in the sleeve. Position this signal in the center of the window. Adjust the span so that the signal occupies approximately 8 grid divisions. The [ ] Lilz channel should be set to 4 grid disisions.
61.3 ArialMcasurcment Scalc - Select the manualscalc option in the locating selectables menu. Using calibration standard data, position the cursor at the center of a known flaw. Set the location with a corresponding 0,0" distance. hiove the cursor to the center of another known flaw or landmark. Adjust the axial distance measurement to the actual distance between tliem as determined by the standard drawing.
6.1.4 Process andMix Channcis -
Process Channel Pl Select [ ] Litz + point channel only for Pl. Rotate Ch Pl so that the response to the 100% TW AShiE s!ceve flaw is in the negative vertical direction and to the right. His can be achieved by simply rotating Pl +/ 180' from the rotation of the raw [ ] Lliz channel.
Process Channel P2 Select [ ] Litz + point channel only for P2. Rotate Ch P2 so that the response to the 100% TW AShiE sleeve flaw is in the negative vertical direction and to the nght. This can be achieved by simply rotating P2 +/ 180' from the rotation of the raw [ ] Lilz channel.
-14
6.1.5 l'oltage Settings -
Position the 100% TW A%IE pNinLluts flaw in the window. Locate and isolate the largest amplitude respo e from the [ ] Litz Ch in the window. Adjust the voltage units for the [ ] Lilz channel to 1.5 volts P P, Save this channel and normalire all of the other channels to this setting 6 2 Caltbratton Curves None are required, but may be used at the option of the analpt Sn 3 point phase angle curves for the sleeve and parent tube. Use additional process channels if needed 6.3 Set Up Tctrain Mapping Terrain map parameters can be set once the axial scale has been set De sure the correct trigger 2
channel is selected and is adjusted properly. The following parameter settings are recommended:
- 2. Tum the crosshatch off for reviewing the data in its most ' natural' fomt l
- 3. Toggle ' Activate Lissajous' to ON to enable the axial ed circ lissajous displays.
l
- 4. Enable the axial filter to AXIAL AVO to be able to toggle the filter on and off.
- 5. Set the X tc.tation to 60 and the Z rotation to 40, adjust as necessary to improve the terrain plot view of tmy particular indication 6._4 Data Screening All data observed on the strip charts and the Lissajous will be evaluated. A terrain plot of the entire j
slees e pressure boundary will be perfomied to ensure full evaluation of all critical locations with
/
particular attention to the weld and expansion transitions.
6.4.1 Strip Charts Set the left strip chart to [ ] Lilz Vertical and the nght strip chart to either the [ ] or { ] Lilz llorizontal for weld centerline locatmg.
t 6.4.2 Lassajous Set the Lissajous to either [ ] Lilz or Pl using the set up span as established by the calibration standard 6.5 Data Evaluation 6 5.1 Evaluation Rcqutrcments - The evaluation addresses the weld region and the expansion and soll transition zones (ETZ/RTZ) of the S/O tube sleeve where flaws are known to have occurred, or are suspect. Other types ofinstalled sleeves may have weld and transition zones of other configuration similar to the ABB CE sleeve and may also fall under this guideline using Analyst judgment. Initial screening of the data will be performed at the setup spans.
l5-
6.5 I limination Requorements (cont a ne regions of the S/G sleeve tube which are addressed with specific analysis methods melude.
the weld area (s) the upper expansion transition the lower expansion transition 6.5.2 Emluation of the I.va er fixpanston Transstoon To dute there have been no known sleeve flaws which have occurred at the lower expansion transition. He lower transition is rolled into the tube in the tubesheet. A [
] band are located in the roll which insure a tight bond to the tube uall. He entical area of the lower expansion is the upper transition which could be a source for anomalies such as PWSCC. It is important to plot a terrain map of this area as well as ralling through the transition. It is recommended to also perform a terrain plot utilizing the ' axial t m. ige' l
tilter. His filter may c.catly reduce the effect of the transition while allowing small indications to be seca more cleath.
l 6.5.3 Emlaa; ton of the Upper thpamson Transstsons Like the lower transition, there have b
been no sleeve flaws uhich have occurred at the upper transitions. He upper transition is expanded into the tube abos e the tubesheet. He parent tube is first prepared by brushmg, honing or ott'er methods. He critical areas of the upper expansion are the transitions. A terrain plot of the transitions should be performed. as well as scrolhng through this area It is recommended to also perform a terrain plot utilizing the ' axial average' filter. His filter may greatly reduce the efTect of the transition, while allowing small indications to be seen more clearly.
6.5.4 limluation of the S/ccvc Wcid Arcas ne installation of ABB/CE sleeves utilizes a welding process in the upper transition of the sleese. Becauw a weld is made which bonds the sleese to the parent tube, it is possible for wcld anomalies to occur in the weld zone. He weld area should be analyzed using the ' axial average' filter with the ( ) kilz frequencies (either l } kHz or Pl) Any volumetric or ' ridge like' indication should be evaluated. Details for recording of these indications can be found in the appropriate sections of the inspection guidelines. If a large amount of r.oise occurs in the tube due to the pilgering of the tube or sleeve, it may be necessary to use a
'circumferential average' filter to aid in the viewing of the weld area. He 'circumferential average' filter should only be used for this type of condition and not for all sleeve tubes, ne welds are expected to have varying noise conditions such as due to geometry and metallographic variations. The analysts' judgment in distinguishing flaw from non flaw conditions is an important consideration when evaluating the data. Here are basically two classifications of weld flaw types: (1) surface mdications which are essentially blow holes, and (2) sub surface indications uhich are weld inclusions and/or weld suckback. Figure 6 5.1 shows a cross sectional view of a sleeve weld with typical locations for the occurrence ofinclusions and sleeve OD suckback. The phase angle relationships among the test frequencies is a useful means for assessing whether an indication is surface or sub surface. Sub surface indications may appear either volumetric or crack like. Also, considenng that a surface indication generally represents a blow.
16-
6.5.4 thuhtarwn ofthe Sleeve Weld Areas (cont W hole type ofindication. it is likely that a reportable surface indication has volumetric characteristics with appreciable amplitude. If the phase angle is mostly flat (O' 20') for all channels, and the amplitude of the signal is small, it is most likely (but not alwa)s) surface geometry. It is difDeult to assign a voltage threshold since it is dependent on field conditions. Herefore, there is no defined voltage threshold for reporting indications. A threshold may be defmed at a later date if the results of further study indicate one is appropriate.
All reportable weld indications are to be identified as WSI for surface indications (possible blow holes) or WZI for weld zone indications (possible sub surface inclusions and/or suckback) in the final report. uc location of the indication relative to the weld centerline is important. De sure to use the procedure as outlined in the guidelines to properly locate the weld centerlme prior to making a report entry. The significance of an indication, whether surface or sub surface, being located above or below the weld centerline is important information to detennine ifit is a rejectable condition. Ris detennination is based on whether or not the pressure boundary is impaired if the indication is above the weld centerline and the UT exam shows adequate fusion of the sleeve to the tube, then it can be determined to be an acceptable condition.
l sw.
Tube ]
4 Weld
(
s h.,
I w
i
- ~
i
[-).
k Figure 6.5.1 - Welded Sleeve Axial Cross Sectional View 17-
6.6 Summary ofPlus Point Coallhammat?vn Cahbratwn Paramercrs Plus Point Coil hiRPC Analpis Summan Table CllANNELS I
2 3
4 5
Pl P2 Channel Span 8 div.
8 div.
8 div 4div.
34div.
8div.
8 div Phase O'
0' 0'
0' 0'
180' 180' 100 %
100 %
100 %
100 %
Trigger 100 %
100 %
Cal Std Siv AShiE Siv AShtE Slv AShtE Siv AShtL Siv AShtE Siv AShiE Curve Optional Optional Optional Optional N'A Optional Optional Volts Norm Norin
[
]
Norm N/A Nonn Nonn i
Ch3 Ch3 Tube AShiE Ch3 Ch3 Ch3 l
7.0 Conclusions and Reconunendations his Appendix 11 qualification etTort for ABB CE welded sleeves has successfully shown detection of the known entical Daws. In sununary, the plus point probe has been qualified for dctccnon of the following conditions:
- 4. Weld suckback within the tube / sleeve pressure boundary The data has been independently reviewed by 3 QDA cemfied arialysts. Table 4.3.1 shows the analysts' results. All Oaw conditions hase been Gagged by at least 2 of the 3 analysts confirming the statistical requirement to show at least the 80% probability-of-detection (POD) with 90%
confidence for each of the Oaw categones.
Accurately locating an indication asially relative to the weld centerline has also been verified. He metallography data showing Daw locarice, as above or below the weld centerline is reliably confirmed with eddy current.
His qualification report is to document the testing and analysis results for the specific Caw types mentioned above. His report may be used as a guide in preparing site-specific acquisition procedures and analysis guidelines.
18 i
ATTACilh1ENT 1 Acquisition Technique Specification (ACTS)
Exammation Scope h1sterial:
Tube Inconel600 Sleeve Inconel690 Outer Diameter & Wall; 3/4" x 0.043" 0.048" [
]
Appiissbility: Exanunation of Auu Cli Uas lungsten Arc (Ul'A) Welded Sleeves with the Plus Point Rotating Probe Instrument:
hilZ Probe:
RPC 51anufacturer:
Zetec, Inc.
Type:
Plus Point h1odel:
18A,30 51anufacturer: Zetec, Inc.
Software:
Eddynet95 Size:
0.520" htig / Rev: Zetec, Inc. / Rev 1.9 or later Part #:
[
]
l Probe Pusher:
Zetec. Inc. 4D.10D l
Cables
(
Probe Cable: 500 h1RPC / 52h1U Extens, Cable: 10 pin Type:
Std Speed h1RPC hiotor Unit Type:
Profilometry Length:
50' Length:
50' Frequencies Stode: Differential Stode:
Channel / Frequency / Gain / Drive Voltage:
Channel / Frequency / Gain / Drive Voltage:
1
[ ] kilz coil 1, gain x2,12.0 v 9-2 - [ ] kilz coit 1, gain x2,12.0 v 10 -
3 - [ ] kllz coil 1, gain x2,12.0 v Ii -
4
[ ] kilz coil 1, gain x2,12.0 v 12 -
5 - [ ] kHz coil 3 (trigger), gain x2,12.0 v 13 -
6-14 -
7 15 -
8-16 -
Calibration Standard: various Sampling Rate:[ ] samples /sec.
lksta Recording Equip, Stig: Hewlett Packard blodel: Senes 6300 - 650/A,650/C or equiv.
hiedia:
650 h1B Rewntable Optical Format: 20 k inodes Scan Pattern & Probe Speed Direction: lielical,270 300 rpm Probe Pull Speed: [ ]/sec max.
Pitch / Axial Sampling: 0.020-0.022"/rev ("/samp) Cire Sampling:
0.020 0.022"/ sample 19-
ATTACllMENT 2 Analysis Technique Specification (ANTSI Ants #: Plus Point SCC. Blowhole. Suckback/ inclusion Detection Quahfication lustrument:
hiiz 30 Manufacturer:
Zetec Model:
2.4.8 Suitu are/ Mfg /Itet:
Zetec Eddy 951.x,2.x Channel Setup i
i Span:
100% TWil in Sleeve W 8 div.
Phase:
100% TWil in Sleeve llorizontal with asial signal up Cal. Std.:
Parent tube /Steese with 100% TWil in each in unexpanded area Curve:
No Curve
[ ] kil All xtti igs same as l l Litz
[ ] Ll!r All settings same as [ l kilz Volts:
[ jv on 100% TWil in parent tube save to all channels
[ ] All:
All settings same as [ ] kilz except Spun Span:
100% TWil in Sleeve 4 4 div.
Pi - ( ) Lil rotated I80 degrees (circ. indscatsons up)
All settings same as [ ] kilz P2 -[ ] kilt rotated 180 degrees (corc. indications up)
All settings same as l l Lilz Screen Setup:
Left stnp chart should be set to [ ] kilz vertical. Right stnp charts may be set up as desired, however [ ] or [ ] kih.irip chart horizontal is used for location of the wcid centerline, and is recommended. [ ] kilz lissajous should be placed in the window for initial screening.
20-
Anal) sis Technique Specification (ANTS) (cont'd)
Analpis Guidelines:
Terrain plot the entire sleeve area using the l ] Ulz at a rninimunt it is recommended to use the Axial Average filter for roll tranution areas.
Locate the weld centerline utilizing the [ l or [ ] Lilz channel honiontal strip chart. Adjust the chart length so the espansion area occupies at least 20 30% of the strip chart. Locate cach end of the weld ione by observing uhere the nominal transition breais. Estimate the center between these tuo points as the weld centerline and locate the appropriate landmark label. Measurements positive from the centerline should be up in the sleeve in respect to gravity.
For weld indications, locate each indication in respect to the weld centerline. Use the most conservative measurement by taking the lowest (in respect to gravity) peak as the indication location.
Other indications may be located from the sleeve ends or other landmarks as appropnate. The l
) kih frequency will aide in determining if the indication is located in the sleeve or the parent tube.
21-
Appendix A Drawings of EDM Sleeve Samples and ECT Printouts ALL PROPRIETARY INFORMATION
Appendix B 1
Welded Sleeve Samples ECT Printouts All, PROPRIETARY INFORMATION
_... -..