A comparative study of acoustic emissions from pencil lead breaks on steel and aluminum substrates using signal analysis.

Fatukasi, Oluseyi S.; Abolle-Okoyeagu, C.J.; Pancholi, K.

Abstract

Pipeline infrastructure plays a crucial role in various industries, such as water management, transportation, oil and gas. Detecting and monitoring potential failures or leaks in pipelines is of paramount importance to ensure safety, prevent environmental damage and optimize maintenance strategies. Acoustic emission (AE) is a passive non-destructive testing technique commonly used in pipeline monitoring. It detects faults caused by leaks, cracks and external impacts in various engineering materials. Calibration is an important aspect of any AE monitoring process, and the Pencil-lead break (PLB) technique is highly effective in the characterization of acoustic wave speed and calibration of the AE experimental setup. Producing a PLB AE source involves breaking a 0.3mm diameter pencil lead by pressing it against the surface of a test structure and applying a bending moment. This produces energy in the form of elastic stress waves, which propagate through the test structure before being recorded and transformed into electrical signals by a transducer mounted on the test surface. In this paper, a comparative study of the behaviour of steel and aluminum substrates based on their time-frequency energy distribution from the burst impact of pencil lead breaks is conducted. This is achieved by simulating AE PLBs in a controlled laboratory experiment on the surfaces of solid steel and aluminium cylinders (200mm diameter) respectively, to generate acoustic emission signals captured by the Piezoelectric transducer attached to the test objects. The acquired signals were analyzed using MATLAB software to study the differences in spectral behaviour on the test objects. The results indicate that the AE energy and average frequency are lower in the solid steel cylinder than in the aluminium cylinder due to differences in their relative density and strength. The response model will serve as a theoretical basis for future structural AE monitoring of oil and gas pipelines.

Citation

FATUKASI, O.S., ABOLLE-OKOYEAGU, C.J. and PANCHOLI, K. 2024. A comparative study of acoustic emissions from pencil lead breaks on steel and aluminum substrates using signal analysis. In Proceedings of the 2024 Society of Petroleum Engineers (SPE) Nigeria annual international conference and exhibition (NAICE 2024), 5-7 August 2024, Lagos, Nigeria. Hosted on OnePetro [online], paper number SPE-221670-MS. Available from: https://doi.org/10.2118/221670-MS

• Presentation Conference Type: Conference Paper (published)
• Conference Name: 2024 Society of Petroleum Engineers (SPE) Nigeria annual international conference and exhibition (NAICE 2024)
• Start Date: Aug 5, 2024
• End Date: Aug 7, 2024
• Acceptance Date: May 20, 2024
• Online Publication Date: Aug 5, 2024
• Publication Date: Aug 5, 2024
• Deposit Date: Aug 6, 2024
• Publicly Available Date: Sep 12, 2024
• Publisher: Society of Petroleum Engineers
• Peer Reviewed: Peer Reviewed
• Article Number: SPE-221670-MS
• ISBN: 9781959025474
• DOI: https://doi.org/10.2118/221670-MS
• Keywords: Acoustic emission; Pencil lead break; Non-destructive testing; Material properties; Wave propagation; Pipeline monitoring; Non-destructive testing
• Public URL: https://rgu-repository.worktribe.com/output/2299302
• Additional Information: The files accompanying this record are the presentation slides. The full-text paper is available to purchase from OnePetro: https://doi.org/10.2118/221670-MS