TPT May 2020

Above and beyond non-destructive testing EDDY currents are a powerful technology for non-destructive testing (NDT) to check the surface quality of metallic long products. Most of the existing applications are based on the use of differential or absolute coils and probes to find discontinuities due to flaws or any characteristic changes like conductivity or hardness. In addition, these measures can be used for the automatic rolls setting avoiding the different speed between rolls and material that produces defects and cobbles. This is solved through the MASSdiscover family. Eddy technology is enormously reliable and easy to maintain and delivered at an attractive cost.

Other solutions, like laser or vision, are more expensive and environmentally depen - dent, making their application difficult.

There are many possibilities with hot and cold rolled long products. Eddy currents deliver countless value when long bars are rolled, because they are not affected by the manufacturing variables, being resistant to many of them. The Ø5.5 hot rolled wire rod – eddy current coils are used to find surface defects when the bar reaches its end shape and dims. It is usually placed after the finishing block. These coils work at both high temperature and speed, without any influence from steam, water or foreign matter (except incrustations or hairs that

Therefore, eddy current applications cover not only traditional uses, like non- destructive surface testing, but they also measure mass (section) and speed at any point of the rolling mill. And rolling mills can get a powerful map of defects including mass measures that add value to every high quality steel maker.

are considered rolling defects). On the other hand, vision systems are affected by the environment. This is the source of the solutions: HOTdiscover and EDDYeyes. ISEND has applied its technological knowledge in this production environ- ment, developing a new coil generation that can be used at any point of the rolling mill to measure the instant mass and speed accurately.

ISEND www.isend.es

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MAY 2020