Installed UT sensors can provide better visibility around how, when, and why corrosion is happening in assets and allows people to track and monitor with extremely high precision (.001"). Owner operators can then overlay corrosion rate data with process data to analyze Integrity Operating Windows (IOWs) and help them better understand how to most efficiently and safely operate their assets and either remediate or extend their useful life, thus moving from a time-based maintenance interval to that of a predictive based interval. This paper will cover a real-life example of how an owner operator has used permanent or temporarily installed wireless UT sensors to monitor problematic areas, track remediation tactics, and verify the ramification of operational changes.
Many asset owners struggle to identify the root cause of fluctuating corrosion rates due to unreliable inspection data. Facilities worldwide are tasked with monitoring thousands of Condition Monitoring Locations (CMLs) with established NDE techniques such as manual ultrasonic testing and radiography. While these techniques can provide valuable "snapshots" of the condition of particular locations, limitations and inherent errors can compound leading to ill-advised decision making. Manually taken thickness data can vary greatly and result in unwarranted complacency or excessive and costly inspections. Utilizing long range wireless continuous monitoring systems have drastically improved operators understanding of how process changes influence corrosion rates. Installed UT sensors provide near real-time data with a 0.001" accuracy. This influx of data provides a trend line whereas with manually taken data, sometimes only taken a few times a year, only provides a few points on a graph. Asset owners have realized they can use this wealth of new information to validate and discover the effects of operational changes on corrosion rates.
Remote systems supplement piping inspection programs by providing accurate, repeatable data. After locating areas of interest with other established inspection techniques such as manual UT or AUT, remote systems can be used to confirm corrosion rates and help make well informed decisions about the remaining life of stationary equipment. When these systems confirm the absence of corrosion activity at a particular CML, inspection resources can be reallocated to higher risk locations. By helping locate areas of higher and lower likelihoods of corrosion, inspection resources can be optimized while simultaneously decreasing the overall risk of unexpected equipment failure within a unit.
