96234947 Phased Array UT Versus RT Report Truncated

TUBE BUTT WELD SAMPLE 7C-040 2.5Diameter X .180 Nominal Wall Thickness

RT Detection

PAUT Detection

Actual

Height - .094 Height - .067 Height - .130

.21

.24

0

0

7.850


0

0

.19

.35 .35

.51 .28

Flaw #1 Flaw #2 Flaw #3 OD

ID

OD

ID

ID

OD

7.850 .25

Flaw #1 Flaw #2 Lack of Fusion Slag Inclusion

Babcock & Wilcox Canada Tube to Tube Butt Weld Nondestructive Examination


.14

.24

0

0

7.850


0

0

.69

.51 .41

.47 .43

Flaw #1 Flaw #2 Flaw #3

OD

ID

OD

ID

ID

OD

7.850


RT Detection

PAUT Detection

Actual


0

0

6.280



0

0

.31

.54 .55 .56

.55 .71 .71


ID

OD

ID

ID

OD

6.280

TUBE BUTT WELD SAMPLE 7C-042 2Diameter X .260 Nominal Wall Thickness

Actual

RT Detection

PAUT Detection

Flaw #1 Flaw #2

Flaw #3

Lack of Fusion Lack of Fusion

ID Undercut


Flaw #2

Lack of Fusion

Height - .067 Height - .028

0

0

6.280 Height - .126 Height - .141

Height - .0

0

0

.75

1.17 .34 .29

.39 .55 .04


ID

OD

ID

ID

OD

6.280 .22 .44

Height ( -.202)

Flaw #1

Flaw #3

TUBE BUTT WELD SAMPLE 7C-043 2Diameter X .260 Nominal Wall Thickness

Actual

PAUT Detection

RT Detection

Incomplete Penetration

Lack of Fusion



.25 .38

.12

.40 .25

.51

0

0

7.850


0

0

.44

.21


ID

OD

ID

ID

OD

7.850


RT Detection

PAUT Detection

Actual

Flaw #1 Flaw #2

Flaw #3

Lack of Fusion and Small Pore

Lack of Fusion and Small Pore

Excess Penetration


TUBE BUTT WELD SAMPLE 1-1 2Diameter X .165 Nominal Wall Thickness

Flaw #1 Flaw #1

Flaw #2

Porosity Cluster Porosity Cluster

Root Concavity

Flaw #3

Root Concavity

Lack of Fusion



.08

Root Porosity

.08

0

0

6.090

Height (- .029)

Height - .130

0

0

.13

.12

.13

.20


ID

OD

ID

ID

OD

6.090 .13

Actual

PAUT Detection

RT Detection

TUBE BUTT WELD SAMPLE 1-3 1.75Diameter X .200 Nominal Wall Thickness

No Flaw Discovered During Cross Sectioning

Flaw #1 Flaw #2

Flaw #3

Porosity Cluster

Porosity in Root


Height - .075

.35

.44

.35

0

0

5.510

Height - .090

Height (-.133)

Height - .0

0

0

.59

.35

Flaw #1 Flaw #2 OD

ID

OD

ID

ID

OD

5.510 .38

Flaw #1

RT Detection


Actual

PAUT Detection

Flaw #1 Flaw #2

Porosity Cluster

Excess Penetration


.56

Height - .083

.43

Flaw #1

.47

0

0

7.850 Height - .142

Height - .142

Height - .146

0

0

.50

.65 .50

Flaw #1 Flaw #2

OD

ID

OD

ID

ID

OD

7.850

RT Detection

PAUT Detection

Actual


Flaw #1 Flaw #1

Flaw #2

Incomplete Penetration Incomplete Penetration

Porosity Cluster


.22 .10 .63

Height Cap Por - .075

Height - .067

.47

Flaw #1

.59

0

0

7.850 Height - .168

Height LOF - .097

Height - .106

0

0

.56 .55

Flaw #1 Flaw #2

OD

ID

OD

ID

ID

OD

7.850

Flaw #3

Actual

PAUT Detection

RT Detection

Flaw #1

Flaw #3

Flaw #2

No Flaw Discovered During Cross Sectioning

TUBE BUTT WELD SAMPLE 2-2 2Diameter X .165 Nominal Wall Thickness

Lack of Fusion and Small Pores Slag Inclusion and Small Pore


Overview of Examination Results

.16 Root Porosity Height (-.021)

.07

Undercut Height - .009

Height - .020

Flaw #1 Flaw #1

.25

.85

.39

0

0

5.970

Height - .037 Height .032


0

0

.59

.28

Flaw #2 OD

ID

OD

ID

ID

OD

5.970 .19

Flaw #3

.12

.08

Actual

PAUT Detection

RT Detection

Flaw #1 Flaw #2

Flaw #3a Flaw #3b

Root Concavity ID Undercut

Root Porosity ID Undercut


The results of the radiographic, phased array ultrasonic and destructive examination results have been graphically presented. Figures #4 through #6 present the detection and height sizing results with calculated maximum and average height sizing error provided by the phased array ultrasonic examination. The radiographic examination method is incapable of providing flaw height data, however, the flaw detection has been shown. Figures #7 through #9 provide the flaw length sizing capabilities for both the RT and PAUT techniques and Figure #10 provides the flaw positioning capability of the PAUT technique with respect to the nearest surface of the tube (ID or OD). The following graphs have been divided into three flaw groups, planar flaws, volumetric flaws and geometric flaws. These groupings were established based on flaw service severity, variations in sizing methodologies with the PAUT technique and obvious differences in detectability between the PAUT and radiographic methods. For the purpose of this investigation flaws determined to be lack of fusion, incomplete penetration, or cracking have been deemed planar flaws. Flaws determined to be slag inclusions or porosity have been deemed volumetric flaws and flaws determined to be excess penetration, undercut or concave root have been deemed to be geometric flaws. Detection and Height Sizing Capability

Planar Flaws

Figure #4

Planar Flaw Detection and Height Sizing

00.020.040.060.080.1

0.120.140.160.180.2

7C-0

40 F

law

# 1

7C-0

40 F

law

# 3

7C-0

41 F

law

# 1

7C-0

41 F

law

# 2

7C-0

42 F

law

# 1

7C-0

42 F

law

# 2

7C-0

42 F

law

# 3

7C-0

43 F

law

# 1

7C-0

43 F

law

# 2

7C-0

44 F

law

# 2

1-7

Flaw

# 1

1-8

Flaw

# 1

1-8

Flaw

# 3

Sample #/Flaw #

Flaw

Hei

ght (

inch

es)

ActualPAUTRT

* Maximum PAUT Height Sizing Error - .113"* Average PAUT Height Sizing Error - .039"* RT height sizing - not applicable - red columns indicate detection only

Observations


1. Six of the twelve planar flaws found during destructive examination were not detected during radiographic

examination. Of these, all except 7C-043 Flaw #1 which was misinterpreted as a volumetric flaw by PAUT, were rejected by the PAUT examination. One planar flaw found by radiography was not confirmed by destructive evaluation. All planar flaws confirmed by destructive evaluation were detected by the phased array ultrasonic examination.

2. On average the PAUT height sizing capability (.039) was best when the subject flaw was planar in nature

versus volumetric or geometric. The maximum height sizing error (.113) occurred when sizing Sample 7C-043 Flaw #1 which was also misinterpreted as a volumetric type flaw.

Volumetric Flaws

Figure #5

Volumetric Flaw Detection and Height Sizing

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

7C-0

40 F

law

# 2

7C-0

44 F

law

# 1

1-1

Flaw

# 1

1-1

Flaw

# 2

1-1

Flaw

# 3

1-3

Flaw

# 2

1-7

Flaw

# 2

1-8

Flaw

# 1

1-8

Flaw

# 2

2-2

Flaw

# 3

a

Sample #/Flaw #

Flaw

Hei

ght (

inch

es)

ActualPAUTRT

* Maximum PAUT Height Sizing Error - .110"* Average PAUT Height Sizing Error - .059" * RT Height Sizing - not applicable - red columns indicate etection only

Observations

1. Three of the nine volumetric flaws found during destructive evaluation were not detected during phased array ultrasonic examination. Of these three flaws, Sample 1-8 Flaw 1 was the only RT rejectable flaw. RT and PAUT detected a volumetric flaw (pore) in Sample 1-1 that was not observed during destructive evaluation. All volumetric flaws confirmed by destructive evaluation were detected by the radiographic examination.

2. Significant PAUT flaw sizing error was noted on several volumetric flaws (Max. .110, Avg. .049). In all

instances volumetric flaws were undersized for height by the PAUT technique.

Geometric Flaws


Figure #6

Geometric Flaw Detection and Height Sizing

-0.25

-0.2

-0.15

-0.1

-0.05

0

0.05

0.17C

-041

Fla

w #

3

7C-0

43 F

law

# 3

7C-0

44 F

law

# 3

1-3

Flaw

# 1

2-2

Flaw

# 1

2-2

Flaw

# 2

2-2

Flaw

# 3

b

Sample #/Flaw #

Flaw

Hei

ght (

inch

es)

ActualPAUTRT

* Maximum PAUT Height Sizing Error - .192"* Average PAUT Height Sizing Error - .052"* RT height sizing - not applicable - red columns indication detection only

Observations

1. The minor root concavity in Sample 7C-044 Flaw #3 was not detectable by the PAUT technique. This flaw was detected and accepted by RT. The minor undercut flaw in Sample 2-2 Flaw #3b was not detected by RT. This flaw was recorded and accepted by PAUT.

2. The excess penetration flaws in Sample 7C-043 Flaw #3 and Sample 1-3 Flaw #1 were marginally detected by the PAUT technique, however, this technique provides no insight into the severity of the excess penetration condition.

Length Sizing Capability

Planar Flaws Figure #7

Planar Flaw Length Sizing

00.10.20.30.40.50.60.70.80.9

1

7C-0

40 F

law

# 1

7C-0

40 F

law

# 3

7C-0

41 F

law

# 1

7C-0

41 F

law

# 2

7C-0

42 F

law

# 1

7C-0

42 F

law

# 2

7C-0

42 F

law

# 3

7C-0

43 F

law

# 1

7C-0

43 F

law

# 2

7C-0

44 F

law

# 2

1-7

Flaw

# 1

1-8

Flaw

# 1

1-8

Flaw

# 3

Sample #/Flaw #

Flaw

Len

gth

(inch

es)

ActualPAUTRT

* Maximum PAUT Length Sizing Error - .26"* Average PAUT Length Sizing Error - .120"* Maximum RT Length Sizing Error - .56" * Average RT Length Sizing Error - .294"

Observations


1. Planar flaws are oversized for length by PAUT in 67% of the sample flaws. Planar flaws are not detected, or

are undersized for length, by RT in 92% of the sample flaws.

Volumetric Flaws Figure #8

Volumetric Flaw Length Sizing

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

7C-0

40 F

law

# 2

7C-0

44 F

law

# 1

1-1

Flaw

# 1

1-1

Flaw

# 2

1-1

Flaw

# 3

1-3

Flaw

# 2

1-7

Flaw

# 2

1-8

Flaw

# 1

1-8

Flaw

# 2

2-2

Flaw

# 3

a

Sample #/Flaw #

Flaw

Len

gth

(inch

es)

ActualPAUTRT

* Maximum PAUT Length Sizing Error - .160"* Average PAUT Length Sizing Error - .076"* Maximum RT Length Sizing Error - .130"* Average RT Length Sizing Error - .063"

Observations

1. On average volumetric flaws are more accurately sized for length, by both PAUT and RT, than planar or geometric flaws.

Geometric Flaws

Figure #9

Geometric Flaw Length Sizing

0

0.2

0.4

0.6

0.8

1

1.2

1.4

7C-0

41 F

law

# 3

7C-0

43 F

law

# 3

7C-0

44 F

law

# 3

1-3

Flaw

# 1

2-2

Flaw

# 1

2-2

Flaw

# 2

2-2

Flaw

# 3

b

Sample #/Flaw #

Flaw

Len

gth

(inch

es)

ActualPAUTRT

* Maximum PAUT Length Sizing Error - 1.130"* Average PAUT Length Sizing Error - .277"* Maximum RT Length Sizing Error - .420"* Average RT Length Sizing Error - .196"


Observations

1. Geometric flaw length sizing is less accurate with PAUT than any other flaw type. On average RT length sizes geometric flaws more accurately than planar flaws and less accurately than volumetric flaws.

PAUT Subsurface Flaw Positioning Capability

Figure # 10

PAUT Subsurface Flaw Position Error Versus Actual

-0.14

-0.12

-0.1

-0.08

-0.06

-0.04

-0.02

0

0.02

0.04

0.06

0.08

7C-0

40 F

law

# 2

7C-0

41 F

law

# 2

7C-0

42 F

law

# 3

7C-0

43 F

law

# 1

7C-0

43 F

law

# 2

7C-0

44 F

law

# 1

1-1

Flaw

# 2

1-3

Flaw

# 2

1-7

Flaw

# 2

1-8

Flaw

# 1

1-8

Flaw

# 2

Sample # / Flaw #

PAU

T Er

ror (

inch

es)

0 Error Based on Actual PositionPAUT Positional Error from Nearest Surface

- Away From Nearest Surface

+ Towards Nearest Surface

* Maximum PAUT Flaw Position Error - .114"* Average PAUT Flaw Position Error - .046"

Observations

1. The general trend reveals the PAUT examination to place the flaw on average .046 further away from the nearest surface (OD/ID) than was found during the destructive examination.

2. The above graph includes both planar and volumetric flaws that were either detected by PAUT and recorded to be subsurface, as well as, those that were found to be subsurface during destructive evaluation. Geometric flaws are inherently associated with surface conditions, therefore, have not been included.


Summary of Critical Examination Characteristics

Table #2

Critical Flaw Evaluation Characteristic

Phased Array Ultrasonic Examination

Radiographic Examination

Flaw Detection 1) Planar Flaws

2) Volumetric Flaws

3) Geometric Flaws

1) All planar flaws detected

2) 67% of volumetric flaws detected

3) 86% of geometric flaws detected

1) 50% of planar flaws detected

2) All volumetric flaws detected

3) 86% of geometric flaws detected

Flaw Height Sizing 1) Planar Flaws

2) Volumetric Flaws

3) Geometric Flaws

1) Average error - .039

Maximum error - .113





No Information Available

Flaw Length Sizing 1) Planar Flaws

2) Volumetric Flaws

3) Geometric Flaws






Maximum error 1.130





3) Average error .196


Flaw Position Location Within the Weld Cross Section

Average error - .046


No Information Available

General Observations from Investigation


Figure #11 Planar Surface Flaws

Class 1 & 2 Ferritic Piping Welds - Surface Flaws Aspect Ratio 0.0

ASME Section XI Table IWB-3514.1

0.0120.014

0.0150.016

0.0180.019

0.021

0.000

0.005

0.010

0.015

0.020

0.025

0.15

0.16

0.17

0.18

0.19 0.

2

0.21

0.22

0.23

0.24

0.25

0.26

0.27

0.28

0.29

Material Thickness (Inches)

Max

. Fla

w H

eigh

t 'a'

(Inc

hes)

Max. Flaw Height

Note: Aspect Ratio 0.0 assumes that the length of the flaw is infinite

Figure #12 Planar Surface Flaws

Class 1 & 2 Ferritic Piping Welds - Surface Flaws Aspect Ratio 0.20 thru 0.50


0.0150.017

0.0190.021

0.0230.025

0.027

0.000

0.005

0.010

0.015

0.020

0.025

0.030

0.15

0.16

0.17

0.18

0.19 0.

2

0.21

0.22

0.23

0.24

0.25

0.26

0.27

0.28

0.29


Max

. Fla

w H

eigh

t 'a'

(Inc

hes)

Max. Flaw Height

Note: Aspect Ratio is calculated from the flaws length (l) and height (a)

a/l = AR, therefore, the flaws length (l) is l = a/AR

Figure #13 Planar Subsurface Flaws


Class 1 & 2 Ferritic Piping Welds - Subsurface Flaws Aspect Ratio 0.00


0.0300.034

0.0370.041

0.0450.048

0.052

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.15

0.16

0.17

0.18

0.19 0.

2

0.21

0.22

0.23

0.24

0.25

0.26

0.27

0.28

0.29


Max

. Fla

w H

eigh

t '2a

' (In

ches

)

Max. Flaw Height

Note: Aspect Ratio 0.0 assumes that the length of the flaw is infinite

Figure #14 Planar Subsurface Flaws

Class 1 & 2 Ferritic Piping Welds - Subsurface Flaws Aspect Ratio 0.20 thru 0.50


0.0370.041

0.0460.050

0.0550.060

0.064

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.070

0.15

0.16

0.17

0.18

0.19 0.

2

0.21

0.22

0.23

0.24

0.25

0.26

0.27

0.28

0.29


Max

. Fla

w H

eigh

t '2a

' (In

ches

)

Max. Flaw Height

Note: Aspect Ratio is calculated from the flaws length (l) and half the flaws height (2a/2)

a/l = AR, therefore, the flaws length (l) is l = a/AR

In order to classify a flaw as a wholly subsurface flaw and apply the examples of a less restrictive acceptance criteria given in Figures #13 and 14, the flaw must be at least a distance from the nearest surface equal to its height. Otherwise, the criteria becomes more restrictive incrementally as the flaw is positioned nearer the surface. When the flaw is less


than 40% of its own height from the nearest surface it is considered to be a surface flaw and the ligament of sound material between the flaw and the surface is then added to the height of the flaw.

The criteria devised by Metalogic, whereby a planar flaw is rejected if its dimensions

exceed .24 long X .020 height and it is not separated from the nearest surface by at least .04 to .06 dependent on tube wall thickness, appears to be conservative. This flaw dimension provides an aspect ratio of ~.05 and would clearly be acceptable for any of the tube thicknesses involved in this investigation, as shown in Figure #15

Figure #15

Class 1 & 2 Ferritic Piping Welds - Subsurface Flaws Aspect Ratio 0.05


0.0310.035

0.0390.043

0.0470.050

0.054

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.15

0.16

0.17

0.18

0.19 0.

2

0.21

0.22

0.23

0.24

0.25

0.26

0.27

0.28

0.29


Max

. Fla

w H

eigh

t '2a

' (In

ches

)

Max. Flaw Height

Documents

96234947 Phased Array UT Versus RT Report Truncated