Volumetric Scanningfor

External Corrosion Measurement

Problem Identification

L1

L2

L3

L1 , 2

L1

L2

L3

L1 , 2

General CorrosionProblem Identification

AA0

L

t

⎥⎥⎥⎥

⎦

⎤

⎢⎢⎢⎢

⎣

⎡

−

−×=

−1

0

0

1

1

MAA

AA

SS f

Sf = Failure StressS = Yield StressA = Metal loss areaA0 = Original areaM = Folias factor f (L,D,t)t = Wall thicknessL = Defect length

Failure Stress Determination

External Corrosion

Corrosion Dimension Measurements

Worst Depth Profile

Corrosion Dimension Measurements

Corrosion Dimension Measurements

General goals

1. Depth resolution: 0.1 mm (less than 1% in a 0-13 mm range)

2. Surface density of measured points: 1 point each 10 mm2

3. Automated data acquisition

4. Automated data analysis and evaluation according to standard procedures

Design a device to measure external corrosion in Ø 30” pipelines.

5. Surface to be analyzed: 80° x 1.000 mm

72.000

60.000

48.000

Points to be obtained

400 (17 days)7.2 x 10536

333 (14 days)6.0 x 10530

267 (12 days)4.8 x 10524

Equivalent inMan-hours *

Developed area(mm2)

Diameter(inches)

* Considering 20 sec for measuring one point and downloading it to an analysis center.

Comisión Nacional de Energía AtómicaCentro Atómico Bariloche (CAB)

Instituto BalseiroS.C. de Bariloche

Argentina

Comisión Nacional de Energía AtómicaCentro Atómico Bariloche (CAB)

Instituto BalseiroS.C. de Bariloche

Argentina

Laser sensor

Final design

Scanner Technical SpecificationsScanner Technical Specifications

• Analyzed surface 80° x 1000 mm on a 30” pipe (530 mm x 1000 mm developed area)

• Scanned points 1 line each 3 mm, 176 lines in developed area1 point every 0.95 mm traveled in axial direction, 1052 points per line

• Measurement Density 1 point each 2.85 mm2, 3.5 points in 10 mm2

• Depth resolution precision: 0.1 mm

• Scanning 5 min, full automatic; wireless data acquisition

• Software One touch control, simple, friendly, on line scanning observation

• Presentation Depth sensitive color presentation with cross section views

• Data handling {x,y,z} data in selected point on graph, zoom in/out, spot size, depth filtering, data exportation to coded files, basic report

• Optional data analysis Analysis according standards (RSTRENG), measurement & analysis reports

On Field Device Test

Results on real 30” pipeResults on real 30” pipeAs measured

10.3 mm

20.3 mm

Rel

ativ

e de

pth

Corrosion Measurement

As measured, pipe deformation (axial and transversal)(top) axial cross section view(left) transverse cross section view, in point {x,y} = {516 mm, 336 mm}

Results on real 30” pipeResults on real 30” pipe

10.3 mm

20.3 mm

Rel

ativ

e de

pth

Corrosion Measurement

Image after automatic surface pipe identification and correction(note flat surface on both axis projections)

0.34 mm thick adhesive strip intentionally glued on pipe

0.34 mm thick magnetic face-like figure intentionally fixed on pipe surface

Results on real 30” pipeResults on real 30” pipe

-0.56 mm

6.45 mm

Abs

olut

e de

pth

Corrosion Measurement

Zoom view of a defect

Abs

olut

e de

pth

-0.56 mm

6.45 mm

Abs

olut

e de

pth

Results on real 30” pipeResults on real 30” pipe

Corrosion Measurement

0.00 mm

6.45 mm

Abs

olut

ede

pth

Corrosion MeasurementAutomatic Automatic DDefectefect Identification According Identification According to International to International StandardsStandards

Automatic cluster identification according selected interaction rule (∆x, ∆y), 1x1 or 2x2

Abs

olut

e de

pth

(top cross section view) axial projection of deeper points of selected cluster.Red painted zone is the defect effective length according to RSTRENG analysis of this cluster.

Automatic Automatic DDefectefect Identification According Identification According to International to International StandardsStandardsCorrosion Measurement

Analysis results of selected cluster

Abs

olut

e de

pth

Corrosion MeasurementAutomatic Automatic DDefectefect Identification According Identification According to International to International StandardsStandards