A Sound Solution to Pipeline Inspections

Pipelines play a vital role in the transportation of fluids and gasses, serving as the arteries of various industries, including oil and gas, petrochemicals, water supply, and more. These networks of interconnected pipes facilitate the efficient movement of resources over vast distances, providing a cost-effective and reliable means of transport. The advantages of pipelines include reduced transportation costs, minimal environmental impact compared to alternative methods like truck or rail, and a continuous flow of materials.

Despite their numerous benefits, pipelines are susceptible to degradation over time. Factors such as corrosion, erosion, cracking, and deformation can compromise the integrity of the pipes, leading to potentially hazardous consequences. The risks associated with these defects include leaks, which can result in environmental damage, loss of valuable resources, and pose a threat to human safety.

Regular inspections are needed to identify and mitigate potential issues before they escalate. However, managing the inspection of extensive pipeline networks is a complex challenge. The sheer length and often remote locations of these pipelines make it logistically demanding and financially burdensome to conduct routine inspections. As a result, there is a constant need for innovative technologies and strategies to enhance inspection efficiency and accuracy.

A potential solution to our present pipeline inspection woes was recently revealed by a group of engineers at the University of Bristol. Taking advantage of the falling costs associated with purchasing and deploying mobile robots, they have developed a robotic platform that can crawl through pipelines and both detect and localize defects. When large pipelines need to be inspected, many of these robots can be deployed simultaneously to make short work of the job.

The wheeled robots are each equipped with a single omnidirectional guided acoustic wave transducer. This is a relatively simple option for sensing, which keeps expenses down while also simplifying maintenance. Yet these acoustic wave sensors are also quite capable of scanning the inside of a pipe and locating anomalies.

Before the robot sets out to inspect a pipeline, operators first program it with a predefined path that it is to follow. As it travels along this path, signals from the acoustic wave sensor are bounced off of the walls of the pipe, and the reflections are interpreted by a custom algorithm that is tailored to detect specific types of defects. Once a defect has been detected, the robot switches itself into a localization mode in which another set of algorithms is utilized to determine exactly where the defect is located. The custom algorithms are lightweight, which opens up the possibility of the robots performing the computations onboard, eliminating any reliance on wireless connectivity.

To prove the utility of their robot, the team conducted an experiment inside of a 10 foot length of steel pipe, much like the pipes used in a wide range of industries. Nine defects of various types, ranging from cracks and holes to pits, were intentionally introduced into the pipe. The robot was found to be capable of detecting all of the defects, and localization errors were within 30 millimeters.

The researchers noted that their methods would be applicable to pipes made of other materials, and also to alternate pipe geometries. This suggests that the robots could be effective in real-world pipeline inspections. And based on their early successes with the prototype system, the team is currently looking for industry partnerships that will allow them to test that theory out.