1. 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 08028 (856) 256-5333 http://engineering.rowan.edu/ Progress Report for the Period June 1 – August 31, 2003 PERF 95-11 STEERING COMMITTEE MEETING Adams Mark Hotel, Denver, Colorado September 17, 2003

2. 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

3. 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) along Axis 1 15,000 psi (22,500 lbs) along Axis 2 Low cost

4. S. Mandayam/ECE Dept./Rowan University Specimen Fabrication Provided by Shell Oil Co. 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 Uniaxial and Biaxial Loading simulates axial and hoop stresses of a pressurized pipeline Duplicate specimens machined in-house with saw cut defects

5. S. Mandayam/ECE Dept./Rowan University Construction History: Version 1 Version 2 Clamping method caused deformation of specimen producing spurious AE data Fixed connection caused bending moments and non- uniform loading of specimen Inability to reach desired load - 13.5ksi (20,000 lbs) max load Additional connections for new clamping brackets create extraneous noise producing false AE data Increased loading capability but still not full desired load – 20ksi (30,000 lbs) max load

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

7. S. Mandayam/ECE Dept./Rowan University Why Version 3? Hydraulic design Allows for increasing max load to 30 ksi (45,000 lbs) Controlled loading environment Negligible noise effects with hydraulic loading New clamping brackets Single bracket piece – minimizes noise Designed to withstand forces exceeding maximum loading specs 1” Pinned connections to specimens Allows for movement of specimen to linearize loading Prevents deformation of specimen at connection

8. S. Mandayam/ECE Dept./Rowan University AE Test Platform: Version 3

9. S. Mandayam/ECE Dept./Rowan University Summary of Progress Additional test specimens identical (steel grade and dimensions) to those provided by Shell Oil have been fabricated Version 3 of the AE test platform with hydraulic loading has been built The platform has been tested to provided desired load of 45,000 lbs along Axis 1 and 22,500 lbs along Axis 2 Initial test indicate repeatable loading with minimized extraneous noise

10. S. Mandayam/ECE Dept./Rowan University Future Plans Work with PAC personnel to conduct tests on both in- house and Shell specimens with Version 3 test platform 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 the design of a pressure vessel test platform