Advanced eddy current is a long-proven non-destructive testing (NDT) technology for detecting cracks and other flaws in conductive materials. Most applications—like inspecting welds in oil and gas pipelines, or corrosion in heat exchanger tubes at power plants—involve tests that take place in the field.
Yet only recently have eddy current instruments become truly portable, allowing technicians perform inspections wherever their work takes them, and to do it without compromise.
For example, last year Zetec introduced the MIZ®-21C, the industry’s first handheld eddy current instrument with surface array capabilities.
The MIZ-21C delivers fast, accurate inspections for a wide range of demanding NDT applications. The ergonomic design, long battery life, and intuitive touchscreen mean that technicians can inspect more areas faster than ever without fatigue, and its industry-leading signal quality provides up to 25% better flaw detection capability. Compared to a handheld pencil probe, the MIZ-21C and a Zetec Surf-X surface array probe can reduce inspection time by up to 95%.
And unlike Liquid Penetrant Testing (PT) and Magnetic Particle Testing (MT), an electronic instrument like the MIZ-21C requires no chemicals and produces a digital record of results that you can easily store, share, and compare over time.
What features do technicians look for in a portable eddy current instrument? Here’s what you should know:
– Ergonomics: A small form factor enables users to inspect hard-to-reach areas and components with less fatigue. One test of good ergonomics is whether the inspector can operate the instrument with one hand—with a glove on.
– Connectivity: The more advanced handheld eddy current instruments today have USB, Wi-Fi, and/or Bluetooth connectivity as well as multiple channels to support different probe types.
– Display: A display should be large enough to handle a wide range of modes—for example, two signals side by side, or a reference signal and a live test signal simultaneously. A touch screen can provide additional functionality and convenience.
– Signal-to-noise ratio: Exceptional signal-to-noise ratio helps inspectors distinguish even a small loss of material. Dual-frequency with mixing nearly eliminates the unwanted signals caused by varying air gaps between layers that can “mask” the signal of interest.
– Software: The software that drives an eddy current tool is becoming more capable, and should support single and dual frequency eddy current, rotating scanners, and conductivity with the viewing tools of Lissajous, Sweep, Waterfall, and C-Scan. Fast access to filters and the ability to manipulate signals and views for each application are also important capabilities.
– Battery life: Longer battery life allows the inspector to work through an entire shift without having to stop to change or re-charge the batteries.
From a practical perspective, eddy current testing is ideal for inspections in the field because it requires minimal site prep or the use of chemicals, and it’s effective on painted or coated surfaces. The findings are immediate and precise, and the instrument produces a digital record that makes it possible to share, store, and analyze results.
Portable instruments like the MIZ-21C make it possible to conduct accurate inspections and bring the power of eddy current testing virtually anywhere. When it comes to affordability, performance, accuracy and dependability, Zetec’s eddy current surface array solutions are second to none. For more information, visit www.zetec.com