Latest Electromagnetic Technology Device Improves Inspection Accuracy and Repeatability

Eddy currents are electrical currents induced within conductors by changing magnetic fields. They are commonly used in nondestructive evaluation (NDE) and corrosion monitoring of structures with painted surfaces. The work of eddy current technicians, who specialize in the electromagnetic modality, requires a high degree of accuracy even when working under challenging testing conditions.

Traditionally, technicians relied on service bulletins or paper-based instructions that outline each step of the test to ensure accuracy and their own safety. This, however, can add to the complexity, cost, and timeliness of the testing. It also provides opportunity for error, often requiring a second technician to read the instructions and record the result, which itself is an error trap.

General Electric’s (GE’s) Measurement and Control business recently introduced a first-of-its-kind, handheld electromagnetic inspection technology that integrates testing intelligence and industry experience into an easily adaptable platform. The GE Mentor EM allows technicians to access information and guidance needed to perform efficient and accurate weld, rotary, and surface inspections (Figure 1). By decreasing the need for paper-based service bulletins and cumbersome manuals, the device replaces legacy processes and takes full advantage of the latest technology.

1. Eddy current testing with the GE Mentor EM. On-device workflow applications allow efficient, accurate data collection. Courtesy: GE Measurement and Control

The equipment makes eddy current inspections easier, more accurate, and less time-consuming than in the past. Technicians are given instant access to critical information by simply connecting to a local network to share data, immediately download up-to-date procedures and workflows, and collaborate with Level-3 experts in real time directly from the device. Additionally, reports can be generated on the spot, from the site of inspection. By placing workflows directly on the device, the Mentor helps to ensure strict compliance with codes, guidelines, and standard practices.

According to Lyle Spiess, NDE inspection programs supervisor for South Texas Project (STP) Electric Generating Station, NDE toolboxes need to have the necessary tools to validate material defects. “Intergranular stress-corrosion cracking (IGSCC) on stainless steel material is very difficult to detect with liquid penetrant alone, and the magnetic particle method can’t be utilized. The Mentor is a field unit that provides very reliable IGSCC surface detection with the use of a simple eddy current surface probe,” Spiess said. “We also use the Mentor for our heat exchanger bobbin probe functionality test while our high-end, more expensive, multi-channel units are in the field.”

GE Mentor Create software can be used to create customizable, on-device inspection workflow applications that provide consistent, up-to-date, and easy-to-follow instructions for technicians of all levels. Inspection technicians gain access to on-device photos, procedures, and videos for reference while setting up, acquiring data (Figure 2), or analyzing data. By limiting the range of adjustments available to the operator, the opportunity for error is minimized.

2. Testing in progress. Accessing procedures on the device reduces the potential for errors. Courtesy: GE Measurement and Control

“The menu-driven features of the Mentor allows linking the eddy current technique utilized for examination to the procedures required for guidance,” said Spiess.

“In high-consequence inspection environments, it is essential that technicians have access to the information they need, when they need it,” said Dave Jankowski, North American commercial NPI leader for GE Measurement & Control. “GE Mentor EM with Mentor Create eliminates the cumbersome paper trail traditionally associated with electromagnetic eddy current testing, dramatically improving the safety, efficiency, and accuracy of the testing process. Additionally, GE’s innovative technology will help transform the industry by bridging the skills gap and addressing the current global shortage of experienced inspection personnel in the workforce today.”

The device has a high-resolution display, and its touchscreen is designed to work with gloves. “We at STP find the flexibility of the Mentor useful for many applications,” Spiess said.

Edited by Aaron Larson, a POWER associate editor (@AaronL_Power, @POWERmagazine).