S. Mandayam/ECE Dept./Rowan University Development of an Acoustic Emission Test Platform with a Biaxial Stress Loading System Joseph Oagaro, Shreekanth Mandayam, John L. Schmalzel and Ronnie K. Miller Electrical & Computer Engineering 201 Mullica Hill Road Glassboro, NJ (856) Progress Report for the Period August 22, 2002 – March 31, 2003 PERF STEERING COMMITTEE MEETING Sheraton Seattle Hotel & Towers, Seattle, Washington April 16, 2003

S. Mandayam/ECE Dept./Rowan University Presentation Outline Project Objectives Personnel Test Specimens AE Training and Quality Assurance AE Test Platforms (Design, Development and Results) Version 1 Version 2 Version 3 Summary and Future Work

S. Mandayam/ECE Dept./Rowan University Project Objectives Design and develop test-platforms for performing Acoustic Emission (AE) measurements on defective pipe segments under bi-axial stress conditions Develop empirical relations between stress and AE signal parameters

S. Mandayam/ECE Dept./Rowan University Major Tasks Specimen fabrication Set-up for 2-D Tensile Testing Instrumentation (AE and control) and data acquisition set-up AE testing: collaboration with Physical Acoustics Corporation Signal analysis

S. Mandayam/ECE Dept./Rowan University Conceptual Design: Test Platform Data Acquisition Signal Conditioning Display/ User Interface Specimen Load Cell Simulated Defect Double Acting Hydraulic Ram AE Sensors

S. Mandayam/ECE Dept./Rowan University Test Platform Design Criteria Design Challenges Rigid Frame Biaxial Loading of test specimen 30,000 psi (45,000 lbs) 1 st Dimension 15,000 psi (22,500 lbs) 2 nd Dimension Short manufacturing time Low cost

S. Mandayam/ECE Dept./Rowan University Project Personnel Rowan Dr. Shreekanth Mandayam (PI), Dr. John Schmalzel (Co-PI), Joe Oagaro (Senior ECE), Dan Edwards (Senior ME), John Ludes (Junior ECE), Terry Lott (Junior ME) PAC Dr. Ronnie K. Miller

S. Mandayam/ECE Dept./Rowan University Specimen Fabrication Provided by Shell 0.5” Thick SA-516 grade 70 Steel Coupons Simulated Cracks of varying depths.08”,.16”, and.32” deep Two sets of 3 specimens each

S. Mandayam/ECE Dept./Rowan University In-House Specimen Fabrication ASTM 836 steel specimens Saw-cut defects (80% deep, 2.5” long) Rowan Water Jet Machining Center

S. Mandayam/ECE Dept./Rowan University Collaboration with PAC Rowan personnel were trained on AE system at PAC on August 22, Channel AE system was delivered to Rowan on September 26, 2002 Rowan personnel were trained on system by PAC Project meeting on January 30, 2003 for reviewing test results; design and test modifications suggested

S. Mandayam/ECE Dept./Rowan University AE Test Platforms Version 1 Prototype Design 13.5ksi (20,000 lbs) max load Version 2 Clamping Bracket Modification 20,000ksi (30,000 lbs) max load Version 3 Hydraulic Rams Full Desired load of 30ksi (45,000 lbs)

S. Mandayam/ECE Dept./Rowan University AE Test Platform: Version 1 Frame Load Transducer Specimen Loading Screws Specimen Clamping Bracket

S. Mandayam/ECE Dept./Rowan University FEM Analysis COSMOSWorks FEM analysis of clamping block

S. Mandayam/ECE Dept./Rowan University AE Test Station Construction: Version 1 1/24/2003

S. Mandayam/ECE Dept./Rowan University Testing Parameters Specimen was preloaded to: Axis 1: 10,000 lbs Axis 2: 20,000 lbs AE sensors activated and test run for approximately 30 minutes Crack Depth 60%, Length 2.5”

S. Mandayam/ECE Dept./Rowan University AE Results: Version 1

S. Mandayam/ECE Dept./Rowan University AE Results: Version 1

S. Mandayam/ECE Dept./Rowan University AE Results: Version 1

S. Mandayam/ECE Dept./Rowan University AE Location: Version 1

S. Mandayam/ECE Dept./Rowan University Design Limitations: Version 1 Clamping method caused deformation of specimen producing spurious AE data. Location View shows AE Hit concentration in proximity of clamping brackets Connection from load cell to specimen fixed, causing bending moment and non- uniform loading of specimen Inability to reach desired load

S. Mandayam/ECE Dept./Rowan University AE Test Platform: Version 2 Frame Load Transducer Specimen Loading Screws Specimen Clamping Bracket New Clamping Brackets Pinned connections for ensure uniform loading Max load of 30,000 lbs

S. Mandayam/ECE Dept./Rowan University Testing Parameters AE sensors active throughout loading of specimen Specimen loaded in steps of 2000 lbs up to: Axis 1: 30,000 lbs Axis 2: 15,000 lbs Signal processing to remove spurious data during loading of test platform

S. Mandayam/ECE Dept./Rowan University AE Results: Version 2

S. Mandayam/ECE Dept./Rowan University AE Results: Version 2

S. Mandayam/ECE Dept./Rowan University AE Results: Version 2

S. Mandayam/ECE Dept./Rowan University AE Location: Version 2 COSMOSWorks FEM Model

S. Mandayam/ECE Dept./Rowan University Why Version 3? Hydraulic design Allows for increasing max load to 30 ksi Controlled loading environment New clamping bracket Single pin piece – minimizes noise

S. Mandayam/ECE Dept./Rowan University AE Test Platform: Version 3 Frame Load Transducer Specimen Hydraulic Cylinders Specimen Clamping Bracket

S. Mandayam/ECE Dept./Rowan University Summary of Progress Rowan personnel have been trained in AE testing techniques by PAC Two versions of the biaxial loading test platform constructed – fabrication of third and final version underway AE tests conducted on test specimens fabricated in- house; specimens provided by Shell will be tested on Version 3 AE signatures obtained for 1-D and 2-D loading of the test specimens indicate appreciable differences, demonstrating proof-of-concept of the technique Continuous interaction with PAC for quality assurance.

S. Mandayam/ECE Dept./Rowan University Future Plans Develop Version 3 of the test platform withhydraulic loading Conduct tests on specimens provided by Shell Parameterize AE signature differences between uni- and bi-axial loading of test specimens Generate calibration curves and empirical relationships quantifying 1-D and 2-D stress effects Generate final report summarizing all findings Provide recommendations for design of a pressure vessel test platform