dr. xuesong wang pipeline engineering & supply co ltd. ppsa seminar, 18 th nov. 2009, aberdeen

www.pipelineengineering.com

Dr. Xuesong Wang

Pipeline Engineering & Supply Co Ltd.

PPSA Seminar, 18th Nov. 2009, Aberdeen


Outline• Introduction

– Principle– Features and benefits

• Results– Laboratory experimental results– Field test results

• Application areas

• Summary


Principle • This acoustic pulse will be partially reflected

wherever there is a change in the internal cross sectional area of the pipeline.

• With the knowledge of the speed of sound in the pipeline, the location of features, such as blockages, holes, valves and buckles can be accurately detected and located.

• The technique is non-invasive and in tests has been shown to be capable of surveying both small and large diameter pipelines


Features and benefitsFeatures of the technology

• Easy to fit and operate

• Portable or permanent unit

• Real time / instant analysis

• Operating range of up to 10km

• Pressure up to 5000psi

• ATEX certified

Benefits of the technology•Pipeline surveys in just a few hours•No disruption to normal operations•Continuous monitoring capability•Remote surveying capability•Simple and cost effective


Laboratory test: Water deposit detection

• Different cross section areas of water deposit can be detected.

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

0 20 40 60 80 100

Sig 10.50% 21.70% 36.80% 53.90% 70.50%Solid PVC pipe, 16m, ID 63mm.


Laboratory test: Buckling detection

Less than 3 % cross section area change can be detected.

100m coiled pipe, ID 50mm

0.1 0.2 0.3 0.4 0.5 0.6 0.7-0.3

-0.2

-0.1

0

0.1

0.2

0.3

0.4

Time(secs)

Am

plit

ud

e(v

)

100%97.1%96.1%94.8%91.3%86.4%78.5%73.9%71.0%67.1%

0.235 0.24 0.245 0.25 0.255

-0.2

-0.15

-0.1

-0.05

0

0.05

0.1

0.15

Time(secs)A

mp

litu

de

(v)

100%97.1%96.1%94.8%91.3%86.4%78.5%73.9%71.0%67.1%


Laboratory test: Flow experimental results

• Matched filtering can be used to detect pipeline defects against the noisy background.

0 5 10 15 20 25 30-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

Penetration distance (m)

Am

plit

ud

e (

v)

0 5 10 15 20 25 300

5

10

15


Rel

ativ

e a

mpl

itude

Reflections of 800 Hz waves

Matched filtering analysis

0 5 10 15 20 25 300

200

400

600

800

1000

1200

Rel

ati

ve a

mpl

itud

e


Pipe end

Blockage

Pipe end


Field test: Atmospheric conditions

• Multiple water deposits can be detected over long distance.

X

Y

M1 M2

T1 T2

Pipe Bridge

X

Y

M1 M2

T1 T2

Pipe Bridge

201m

60m

150m

32m

32m

7.5m

10” steel pipe. 1km long

100 200 300 400 500 600 700 800 900 1000-0.03

-0.02

-0.01

0

0.01

0.02

0.03

Distance from source (m)

Am

plitu

de

X valve closedX valve 12% openX valve 22% openX valve 42% openX valve 74% openX valve 98% open

100 200 300 400 500 600 700 800 900 1000

-0.03

-0.02

-0.01

0

0.01

0.02

0.03

Distance from source (m)

Am

plitu

de

A

B

C D E F G

H


Field test: High pressure conditions

Obstruction can be detected over 850m at high pressure conditions.

1 2 3 4 5 6 7 8 9

-0.1

-0.08

-0.06

-0.04

-0.02

0

0.02

0.04

0.06

0.08

Time (secs)

Am

plit

ud

e (

v)

3” steel pipe, 93 psig


Field test: High pressure conditions

• Status can be identified.

0 5 10 15 20 25 30 35 400

0.001

0.002

0.003

0.004

0.005

0.006

0.007

0.008

0.009

0.01

Time (s)

Str

en

gth

of

refle

ctio

n

NormalAbnormal


Field test: High pressure with flow

• Matched filter and band pass filter can be used to remove background noise.

0 2 4 6 8 10-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

Time(secs)R

ela

tive

am

plit

ud

e

No flowLow flowMedium flowHigh flow

1 2 3 4 5 6 7 8 9

-0.015

-0.01

-0.005

0

0.005

0.01

Time(secs)

Rel

ati

ve a

mp

litu

de

Processed data by using matched filtering

Processed data by using a band pass filter

1st reflection

2nd reflection 3rd reflection


Applications• As a temporary installation to detect blockages, obstructions or other

features in a pipeline.

• As a permanent installation to continuously monitor a pipeline and detect changes such as the build-up of hydrate blockage or water deposit.

• Location of partially closed valves.

• Location of stuck pigging tools and plugs.

• Location of dents, hydrates and debris.


Summary• An acoustic reflectometry technique for detecting defects in gas filled

pipelines has been developed.

• Appropriate signal processing techniques, such as band pass filter and matched filtering, can be used to identify features even on a complicated pipeline arrangement with strong noise interference.

• Work is continuing to improve the accuracy and reliability of the method and also to test it on longer lengths of live gas pipeline.

• Monitoring for liquid pipelines is under investigation.


Acknowledgements


Thanks for your attention

Q&A

[email protected]

dr. xuesong wang pipeline engineering & supply co ltd. ppsa seminar, 18 th nov. 2009, aberdeen

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