Knowing that everything is alright at work is now as simple as having access to a computer, tablet, or smart phone. By using wireless sensor technology and cloud data systems to monitor fixed asset corrosion conditions, a user can instantly learn the state of their system and whether it is running properly or if there are any alarms or warnings. Immediate access to critical data, such as wall thickness, can provide engineers and other workers with considerable peace of mind.
In the past, corrosion/erosion monitoring involved manual inspection and the managing of that data. Integrating computers to aid in managing the information was an improvement, but still required collecting it manually and time to transfer the data into the system, which could quickly become obsolete.
Now, however, manual inspection and data entry are no longer required through the use of LoRaWan and the IoT. Instead, users can install sensors in crucial areas of a petrochemical or processing facility (Figure 1). This enables online access to data 24 hours a day, seven days a week, for nearly real-time monitoring.
The ability to retrieve data from the cloud means numerous people have access to the same information regardless of their location (Figure 2). Because of this, the value of the information is multiplied. Researcher Art Leach with Sensor Networks Inc. (State College, Pennsylvania, USA) analyzed the ways in which remote corrosion monitoring can assist asset owners and how it can be of benefit.1
The benefits of remote corrosion monitoring through the use of LoRaWan and IoT technology include the ability to work remotely, increased safety, and long-range capability.
When sensors are fitted onto pipes, tanks, vessels, etc., they are able to determine the ultrasonic thickness measurement and, optionally, a temperature measurement of these assets. This is helpful for facilities in general, but especially during the COVID-19 crisis when personnel have been restricted at some sites. Instead, data can be transmitted via cellular connectivity or radio frequency to a gateway receiver. Through an internet connection, the information is sent to an online software host system. From there, users can retrieve it on virtually any device.
Additionally, because fewer people are required to be on site, the level of safety is increased. Performing manual inspections can be dangerous, but when these are decreased, so is the likelihood of a safety incident. Reducing even one safety incident a year can save a company tens of thousands of dollars.
Utilizing wireless technology also offers the user long-range capability with low-power requirements. One gateway can support thousands of nodes spanning several miles. Furthermore, wireless networks are able to maintain various devices using the same wireless protocol. The battery life of the sensors is long, plus the gateway can connect to third-party cellular networks. The installation is simple and inexpensive, allowing for hundreds or even thousands of sensors to be operated. All of this enables facilities to move from a manual, time-based maintenance interval, to an automated, predictive one.
A Real-World Example
In this example, one refinery asset owner worked cross-functionally with onsite and offsite employees. They were able to make decisions that helped extend the life of a particular area of the plant that historically had problems with wall thickness loss. The departments that worked together included inspection, corrosion, water and chemical, and operations.
First, the inspection team helped the corrosion team identify the cause of localized thinning in critical areas of the unit. Then, the corrosion engineers created a few hypotheses regarding the problem by reviewing data from the prior inspection. Unfortunately, these hypotheses could not be tested since the data was not as precise or timely as needed.
Next, the water and chemical team reviewed the dosage of inhibitor used. They reached out to the operations team for information regarding any changes in operation that may have led to the issues.
Finally, by working together, they determined that operational parameters had changed, plus different feedstock had also been used. Ultimately, by installing wireless ultrasound thickness sensors, they found that during different operating intervals, the use of different types of feedstock and chemical inhibitor, plus operating parameters, allowed them to detect and mitigate the corrosion.
Wireless network technologies have quickly progressed in recent years. Considering the characteristics needed in corrosion monitoring sensors for each particular application is important. These characteristics include power, bandwidth, range, number of nodes, data latency, data security, and cost.
The availability of data thanks to remote ultrasonic monitoring tools means greater productivity. Not only are employees able to monitor corrosion-rate data in almost real time, but they can overlay this information with operational data enabling cross-functional teams to understand the bigger picture.
By employing a wireless system and a cloud-based data repository, asset owners can augment their manual workforce, allowing their employees to “work smarter, not harder.”
1 A. Leach, “Corrosion Monitoring from the Comfort of Your Office, Home, or Car,” CORROSION 2021, paper no. 16519 (Houston, TX: NACE International, 2021).