Biosolids and Odor and Corrosion Conference & Expo The Right Technique for Condition Assessment Programs Glenn H. Willson, P.E. V&A Consulting Engineers
Today We Are Shifting From Building and Operating Assets to Managing Them The Goal is to Look at Long Term Life Cycle Costs Rather Than The Day-to Day Issues
Agenda Discuss Some of the Current Condition Assessment Technologies Address The Issues Associated With The Technologies Provide Relative Costs
Goals of Condition Assessment Program Condition Assessment is usually part of a Asset Management Program Determine Remaining Useful Life Rehab or Replacement Develop Prioritization Develop Schedule
Condition Assessment Program Broadly categorized in two groups: Qualitative and Quantitative Descriptive Photograph Physical Measurement Effective Condition Assessment uses Both Methods
Materials Cast Iron Pipe (CIP) Ductile Iron Pipe (DIP) Steel Pipe Concrete Pipe/Structures
Issues to be Addressed Budget Permitting Traffic Control Accessibility Operations, pressure, flow rate Environmental Amount of Time System Can be Shut Down
Assessment Technologies External Eddy Current Radiography Ultrasonic Testing Internal Acoustic Leak Testing (Internal/External) Automated Technologies CCTV Documentation 3D HD Panoramo Manned Entry
Pulsed Eddy Current Intermediate Cost Broadband Electromagnetic (BEM) CIP, DIP, Steel Test Through Thick Coatings/Corrosion Byproducts (2 +) Provides an Average Wall Thickness
Pulsed Eddy Current Requires Post Processing of Data Non-destructive frequency-independent application of electromagnetic or eddy current BEM scan is not affected by background electromagnetic interference Test frequencies can be adjusted to the specific pipe material and site conditions
Pulsed Eddy Current
BEM
BEM
BEM Data Output
Radiography Low Cost CIP, DIP, Steel and Conventional Concrete Pipe Look at Cross Sectional Area For Wall Loss Reveals Subsurface Inclusions, Defects and Anomalies Requires Licensed Technical Personnel Due to Radiation
Radiography Setup
Ultrasonic Testing (UT) Low Cost Sound Waves Transmitted Through Pipe Wall Thickness Calculated by Sound Wave Travel Time Couplant Required to Transmit Sound to Metal
Ultrasonic Testing (UT)
Ultrasonic Testing (UT) A-Scan Single Point Wall Thickness B-Scan Continuous Scan Transducers/Receivers on Cart
A-Scan Ultrasonic Testing
B-Scan Ultrasonic Testing
Test Data Comparison
Ultrasonic Testing UT Functions Better With: Smooth Surface Profile Homogenous Material Matrix DIP and CIP Matrix is Not Homogenous
Acoustic Techniques Listening for Leaks CIP, DIP, Steel, PCCP and Concrete Pipe Detect Defects, Air Pockets and Leaks Sensors Can Filter Out Background Noise and Hear Leaks
Acoustic Technique Variables Material Pressure Flow Rate Diameter Size of Access Number of Turns Change in Elevation
Acoustic Techniques/Internal Access Higher Cost Tethered Sensor Connected w/ Wire Untethered Sensor Swims/Rolls Miles of Pipe Per Setup Launch/Catch Sensor Monitor Wire Breaks on PCCP
Acoustic Techniques/External Access Intermediate Cost Surface Mounted Sensors Listen to Water Flow Acoustic Signature Correlators Measure the Time The Leak Noise Signal Gets to the Sensors Leak Location is Identified Requires Post Processing of Data
Correlators
Automated Technologies Sonar Sediment Levels Laser Pipe Dimensions Electromagnetics Remote Field Eddy Current Identify Defects Remote Flux Leakage Identify Defects
3D CCTV Panorama 3D Digital CCTV Moves faster than Standard CCTV 2 HD Wide Angle Cameras Data Presented like Google Maps Street View
Manned Entry Safety/Logistics Visual Qualitative Data Physical Quantitative Data
Technology Choice Considerations There is no Silver Bullet What Are You Trying to Determine What is the Required Accuracy Physical Constraints Operational Constraints Budget
Questions Glenn H. Willson gwillson@vaengineering.com