World’s First Electromagnetic Liquid Core Detection System

   In 2007, dynamic soft reduction technology was spread among domestic steel plants. But the calculation of solidification end was affected by many factors, including cooling water, water amount, steel grade, and cross section, etc. So there is big deviation between calculated position and actual position. Thus the application of dynamic soft reduction cannot realize its ideal effect. In view of the particularity of continuous casting slab, the accuracy of the model cannot be verified through online test to the slab. We can only correct the model through offline nail-shooting test. It would produce far-reaching effect to the application of dynamic soft reduction system and F-EMS (final electromagnetic stirring), if we could find a way to conduct online real-time solidification liquid core end detection.

   The working principle of electromagnetic ultrasonic technology is realized by the electromagnetic wave transmitted by the electromagnetic sensor installed on the CCM segment. Different signal feedback can be produced when the electromagnetic waves transmit through solidified slab and molten steel. Through signal analysis we can get liquid core shape and position. RAMON, as the master of sensor detection, has keenly captured this information and determined to develop the unprecedented technology. Professor Tian Zhiheng suggested innovating the sensor structure. He creatively adopted “mushroom” type structure to increase the lift-off distance of the sensor up to more than 5mm and the penetrating thickness of the steel plate up to more than 300mm.

   Nowadays this technology is still in the international leading level. The project put themselves into the experiment immediately since its establishment. At the beginning, under the condition of no professional equipments, no professional devices, and no relevant experience, all team members didn’t not fear but to plunge themselves into the project enthusiastically. The field experiments lasted from October to December, 2007, without collecting any ultrasonic signal from the slab. Instead of feeling discouraged, the project members constantly tried new inspiration and new ideas. Perseverance can always be paid off. At the end of December, the project finally fulfilled zero breakthrough. They have detected weak ultrasonic echo waves from the slab and were greatly encouraged by this progress.

   After numerous attempts, the project team finally achieved online non-contact detection of the solidification end position of the slab with its surface temperature up to 1000℃. The detection precision is ±300mm and the maximum slab thickness is 400mm. They also realized its linkage with dynamic soft reduction system.

   In 2013, RAMON has successfully realized the application of electromagnetic liquid core detection system and dynamic soft reduction system to Liuzhou Steel. Currently, as for this technology, only RAMON has successful application case.

   Sharing our story:

   Mr. Zhang Zhiwei

   Factory director of BOF steel plant of Liuzhou Steel

   Liuzhou Steel has applied many products of RAMON, including electromagnetic liquid core detection system, the application effect of which is remarkable. I wish RAMON will become better and better.