View
42
Download
5
Category
Tags:
Preview:
DESCRIPTION
Acoustic Pipeline Leak Detection Presented by Mark Wood SALDS 2012 Houston TX. Ocean Sonics Ltd. Design & Build Smart Hydrophones Used for Data Presentation Software. Ocean Science Environmental Monitoring Ocean Noise Measurement Sea Mammal Detection Pipeline Leak Detection - PowerPoint PPT Presentation
Citation preview
Acoustic Pipeline Leak Detection
Presented by Mark Wood
SALDS 2012 Houston TX
Design & Build Smart HydrophonesUsed for
Data Presentation Software
•Ocean Science•Environmental Monitoring•Ocean Noise Measurement•Sea Mammal Detection•Pipeline Leak Detection•Vessel Tracking
Ocean Sonics Ltd.
Underwater SoundImportant ToolWorking in the Sea
Learning about the OceanMeasuring the Health of the Sea
Visualization of SoundsAlways a Sub-plot!
Sounds can tell a story Always a Sub-plot!
Ocean Pipelines
Safest way to transport energy
Pipelines ageContent is corrosive
Build-up
DamageStormsAnchors
Avalanche
Ocean PipelinesGulf of Mexico
54,000 km of pipeline in 20072700 km of new pipeline/year avg.
YearDamage Reports
2004 168
2005 542
2008 330
GOM Pipeline Damage 2005
What is a leak?
Crack or split in pipe bodyStress, Construction, Movement
Spot CorrosionContents damage inside lining
Damaged SealStress, Construction, Repair
Open ValveOperator Error
Finding LeaksDo we have a leak?
Hydrostatic TestUnexplained pressure dip
How small is too small?No agreement on this
Leak Sounds
Leak produces a ‘hiss’
UltrasonicEasier to detect visually
Leak Detection
Leak ‘Location’
Avoid False ‘Detects’
Physics of LeaksLeak Types
Frequency Increases with pressure & density
Decreases with leak cross sectional area
Intensity Increases with pressure & density
Decreases with distance from the leak source
Type Liquid Air
Ingress 1 3
Egress 2 4
Physics of LeaksAbsorption Example
Assume a leak sound with average level of 140 dB re.1uPa
120 dB - Easy to detect85dB - Fine in moderate noise
70 dB - Possible only in quiet environment
Range 10 kHz 100kHz
10 m 120 dB 120 dB
500 m 85 dB 70 dB
Pipeline LeakGulf of Mexico
Large Leak from ValveROV mounted
Ship
ROV
Smart Hydrophone
Pipeline LeakROV Thrusters & leak, no filtering
Pipeline LeakROV Thrusters & Leak - Filtered
Pipeline LeakGulf of Mexico
DiverGulf of Mexico
Pipe Repair after Storm500 feet of water
Low visibility
Small leak prevented commissioningSpent 5 weeks looking for leak
Cause: loose needle valve
SoundscapeBreathing regulator
Warm water circulator
DiverGulf of Mexico
Breathing
DiverGulf of Mexico
Leak Sound
DiverGulf of Mexico
Two Events
Large Submerged PontoonGulf of Mexico
ROV Thrusters & Leak
Unfiltered
Large Submerged PontoonGulf of Mexico
Leak Signals
ProgressChallenges Addressed
Signal Quality
•80dB to 120dB dynamic range
•Lower noise floor to Sea State Zero
•Fully Calibrated - units in uPa
Simple Deployment
•Very Small, handheld, Single Cable
•Tactile Feedback
ProgressChallenges Addressed
Increase Reliability
•Tolerate ‘dirty power’
•Log all Survey Data Internally
Improve Event Detection
•Configurable Events based on frequency band & energy
•Sends a message when event triggers
•Autonomous Operation
ProgressWhat’s left to do?
Develop Acoustic/Hydrodynamic Models
•Currently not well understood
•Account for sound channel effects, eg. depth, sea bottom
Develop Feature Extraction Algorithms
•Filters that extract features unique to leaks
•Question of Funding still needs to be answered
ProgressRequirements
Discern False Detects
•Find Characteristics Specific to Leaks
•Develop Feature Extraction Algorithms
Modeling of Leak HydrodynamicsUnderstand properties of Leaks Better
Leak Flow Dynamics
Modeling of Leak HydrodynamicsUnderstand properties of Leaks Better
Environment Inside and Outside PipeNumerical model of pipe flow combined with leak flow
Other Leak ChallengesPipe in Pipe
Is it possible to detect a leak?Change construction to instrument pipe?
Buried Pipe?
Pipeline leaksPassive Acoustics
Proven to be a powerful tool for finding pipeline leaks.
✴ Pipeline surveys using ROV or diver
✴ Deep water, up to 3500m depth
✴ Continuous pipeline health monitoring
✴ Max range function of leak sound intensity
Deeper understanding will improve detection quality
Thank YouMark Wood
Ocean Sonics Ltd.
14 Nov. 2012 Nova Scotia
Recommended