# Application of Ultrasonic Guided Waves for Inspection of High Density Polyethylene Pipe Systems

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## Abstract

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^{®}Focus+ system was used as the pulser/receiver. Optimum frequency range of inspection was at 15−25 kHz due to the level of attenuation at higher frequencies and the larger dead zone at lower frequencies due to the pulse length. A minimum of 14 transducers around the circumference of a 3 inch pipe were required to suppress higher order flexural modes at 16 kHz. According to the studied condition, 1.84 m of inspection coverage could be achieved at a single direction for pulse-echo, which could be improved by using a higher number of transducers for excitation and using pitch-catch configuration.

## 1. Introduction

## 2. Theoretical Background

#### 2.1. Elastic Waves in Solid Media

#### 2.2. Thermoplastic Pipe Inspection

## 3. Laboratory Experiments

#### 3.1. Experimental Set-Up

^{®}Focus+ system was used to excite the transducers. The data acquisition was conducted in the pulse-echo configuration due to the length limitation of the pipe sample. A frequency sweep was conducted from 10 to 30 kHz in 1 kHz increments. A 5-cycle Hann-windowed excitation pulse was applied for a discrete input excitation signal. Using the velocities of the two longitudinal modes, L(0,1) and L(0,2), obtained from the group velocity dispersion curves, the expected time-of-arrival (ToA) at possible reflections are tabulated in Table 2 for a 16 kHz operating frequency.

#### 3.2. Experimental Results

## 4. Numerical Analysis

#### 4.1. Finite Element Model

_{o}), the following equation was used:

_{0}is the center frequency.

_{l}is the group velocity of the longitudinal wave mode at the operating frequency.

#### 4.2. Parametric Study

## 5. Results and Discussion

_{bw}is the frequency bandwidth, and k

_{i}is the bandwidth of the desired lobe, where k

_{i}= 0 is for the main lobe and k

_{i}= 1 is the side lobe.

## 6. Conclusions and Further Work

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

- Ghazali, M.F.; Priyandoko, G.; Hamat, W.S.W.; Ching, T.W. Plastic pipe crack detection using ultrasonic guided wave method. In Proceedings of the Malaysian Technical Universities Conference on Engineering and Technology, Melaka, Malaysia, 10–11 November 2014. [Google Scholar]
- International Atomic Energy Agency (IAEA). Safety of Nuclear Power Plants: Design; IAEA Safety Standards Series No. SSR-2/1; IAEA: Austria, Vienna, 2012. [Google Scholar]
- Duvall, D.E.; Edwards, D.B. Forensic Analysis of Oxidation Embrittlement in Failed HDPE Potable Water Pipes. In Pipelines 2010; American Society of Civil Engineers (ASCE): Reston, VA, USA, 2010; pp. 648–662. [Google Scholar]
- Hunaidi, O.; Chu, W.; Wang, A.; Guan, W. Detecting leaks in plastic pipes. J. Am. Water Work. Assoc.
**2000**, 92, 82–94. [Google Scholar] [CrossRef] [Green Version] - Hou, Q.; Jiao, W.; Ren, L.; Cao, H.; Song, G. Experimental study of leakage detection of natural gas pipeline using FBG based strain sensor and least square support vector machine. J. Loss Prev. Process. Ind.
**2014**, 32, 144–151. [Google Scholar] [CrossRef] - Liu, Z.; Kleiner, Y. State of the art review of inspection technologies for condition assessment of water pipes. Measurement
**2013**, 46, 1–15. [Google Scholar] [CrossRef] [Green Version] - International Atomic Energy Agency (IAEA). Ageing Management for Nuclear Power Plants; IAEA Safety Standards Series No. NS-G-2.12; IAEA: Austria, Vienna, 2009. [Google Scholar]
- Lowe, P.S.; Sanderson, R.M.; Boulgouris, N.V.; Haig, A.G.; Balachandran, W. Inspection of Cylindrical Structures Using the First Longitudinal Guided Wave Mode in Isolation for Higher Flaw Sensitivity. IEEE Sensors J.
**2015**, 16, 706–714. [Google Scholar] [CrossRef] [Green Version] - Rose, J.L. Standing on the shoulders of giants: An example of guided wave inspection. Mater. Eval.
**2002**, 60, 53–59. [Google Scholar] - Wilcox, P.D.; Lowe, M.J.S.; Cawley, P. Mode and Transducer Selection for Long Range Lamb Wave Inspection. J. Intell. Mater. Syst. Struct.
**2001**, 12, 553–565. [Google Scholar] [CrossRef] - Kharrat, M.; Zhou, W.; Bareille, O.; Ichchou, M. Defect detection in pipes by torsional guided-waves: A tool of recognition and decision-making for the inspection of pipelines. In Proceedings of the 8th International Conference on Structural Dynamics, Leuven, Belgium, 4–6 July 2011. [Google Scholar]
- Lowe, P.S.; Scholehwar, T.; Yau, J.; Kanfoud, J.; Gan, T.-H.; Selcuk, C. Flexible Shear Mode Transducer for Structural Health Monitoring Using Ultrasonic Guided Waves. IEEE Trans. Ind. Inform.
**2018**, 14, 2984–2993. [Google Scholar] [CrossRef] [Green Version] - Rose, J.L. Ultrasonic Guided Waves in Solid Media by Joseph L. Rose; Cambridge University Press (CUP): Cambridge, UK, 2014. [Google Scholar]
- Meitzler, A.H. Mode Coupling Occurring in the Propagation of Elastic Pulses in Wires. J. Acoust. Soc. Am.
**1961**, 33, 435. [Google Scholar] [CrossRef] - Silk, M.; Bainton, K. The propagation in metal tubing of ultrasonic wave modes equivalent to Lamb waves. Ultrasonics
**1979**, 17, 11–19. [Google Scholar] [CrossRef] - Bocchini, P.; Marzani, A.; Viola, E. Graphical User Interface for Guided Acoustic Waves. J. Comput. Civ. Eng.
**2011**, 25, 202–210. [Google Scholar] [CrossRef] - Zhu, J.; Collins, R.P.; Boxall, J.; Mills, R.S.; Dwyer-Joyce, R. Non-Destructive In-Situ Condition Assessment of Plastic Pipe Using Ultrasound. Procedia Eng.
**2015**, 119, 148–157. [Google Scholar] [CrossRef] - Hong, X.-B.; Lin, X.; Yang, B.; Li, M. Crack detection in plastic pipe using piezoelectric transducers based on nonlinear ultrasonic modulation. Smart Mater. Struct.
**2017**, 26, 104012. [Google Scholar] [CrossRef] [Green Version] - Cheraghi, N.; Riley, M.; Taheri, F. A Novel Approach for Detection of Damage in Adhesivelybonded Joints in Plastic Pipes Based on Vibration Method Using Piezoelectric Sensors. In Proceedings of the 2005 IEEE International Conference on Systems, Man and Cybernetics, Waikoloa, HI, USA, 12 October 2005; Institute of Electrical and Electronics Engineers (IEEE): Piscataway, NJ, USA, 2006; Volume 4, pp. 3472–3478. [Google Scholar]
- Zhou, C.; Hong, M.; Su, Z.; Wang, Q.; Cheng, L. Evaluation of fatigue cracks using nonlinearities of acousto-ultrasonic waves acquired by an active sensor network. Smart Mater. Struct.
**2012**, 22, 15018. [Google Scholar] [CrossRef] [Green Version] - Corp, S.M. Macro Fiber Composite. Available online: https://www.smart-material.com/MFC-product-main.html (accessed on 17 January 2020).
- Ren, G.; Yun, D.; Seo, H.; Song, M.; Jhang, K.-Y. Feasibility of MFC (Macro-Fiber Composite) Transducers for Guided Wave Technique. J. Korean Soc. Nondestruct. Test.
**2013**, 33, 264–269. [Google Scholar] [CrossRef] [Green Version] - Na, W.-B.; Yoon, H.-S. Wave-attenuation estimation in fluid-filled steel pipes: The first longitudinal guided wave mode. Russ. J. Nondestruct. Test.
**2007**, 43, 549–554. [Google Scholar] [CrossRef]

**Figure 3.**Displacement patterns of the axisymmetric modes (

**a**) L(0,1) (

**b**) T(0,1), and (

**c**) L(0,2). The black arrow represents the direction of propagation, and the red dashed line represents the central axis.

**Figure 5.**Experimental results over a range of frequencies for different transducer configurations and its corresponding time-domain results at 16 kHz: (

**a**) one transducer; (

**b**) two evenly spaced transducers; (

**c**) four evenly spaced transducers; (

**d**) eight evenly spaced transducers.

**Figure 6.**Experimental results over a range of frequency for excitation using 14 transducers and its corresponding time-domain results at 16 kHz.

**Figure 7.**Experimental results over (

**a**) time and (

**b**) range of frequency for excitation at a different number of transducers, illustrating the incremental amplitude increase when the number of transducers increased.

**Figure 9.**Numerical results of 14 transducer case excited at 16 kHz at a different number of cycles in time-domain.

Material Property | HDPE |
---|---|

Young’s Modulus | 1.1 GPa |

Poisson’s Ratio | 0.45 |

Density | 950 kg/m^{3} |

**Table 2.**Calculated time-of-arrival (ToA) for the expected reflections from pipe ends at 16 kHz operating frequency.

Reflection (m) | Expected ToA (µs) | |
---|---|---|

L(0,1) | L(0,2) | |

0.5 | 803.57 | 444.05 |

1.34 | 2150.00 | 1190.05 |

1.84 | 2953.50 | 1634.10 |

**Table 3.**Number of flexural modes corresponded to each family of fundamental modes over a range of frequencies.

Frequency (kHz) | Number of Higher Order Modes | ||
---|---|---|---|

T(0,1) | L(0,1) | L(0,2) | |

10 | 4 | 7 | 2 |

12 | 5 | 8 | 2 |

14 | 6 | 9 | 3 |

16 | 7 | 10 | 3 |

18 | 8 | 11 | 4 |

20 | 9 | 12 | 5 |

Number of Cycles | Frequency Bandwidth [kHz] | |
---|---|---|

Main Lobe | Side Lobe | |

3 | 5.33–26.67 | 0–32 |

5 | 9.6–22.4 | 6.4–25.6 |

10 | 12.8–19.2 | 11.2–20.8 |

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**MDPI and ACS Style**

Lowe, P.S.; Lais, H.; Paruchuri, V.; Gan, T.-H.
Application of Ultrasonic Guided Waves for Inspection of High Density Polyethylene Pipe Systems. *Sensors* **2020**, *20*, 3184.
https://doi.org/10.3390/s20113184

**AMA Style**

Lowe PS, Lais H, Paruchuri V, Gan T-H.
Application of Ultrasonic Guided Waves for Inspection of High Density Polyethylene Pipe Systems. *Sensors*. 2020; 20(11):3184.
https://doi.org/10.3390/s20113184

**Chicago/Turabian Style**

Lowe, Premesh Shehan, Habiba Lais, Veena Paruchuri, and Tat-Hean Gan.
2020. "Application of Ultrasonic Guided Waves for Inspection of High Density Polyethylene Pipe Systems" *Sensors* 20, no. 11: 3184.
https://doi.org/10.3390/s20113184