A study on electromagnetic transducers for the continuous casting process

• Autorzy: Kim, I. S. , Son, J. S. , Kim, H. J. , Chin, B. A.
• Języki publikacji: EN

Abstrakty

EN

Purpose: One of the areas in the continuous casting process that has not been definitively instrumented is a method for reliably locating the part of a continuously cast strand that remains liquid for a period after the outer portion has solidified. Therefore, this paper is focused on the measurement of the solidification point made by a through transmission technique based on the relationship between ultrasonic speed and measured temperature using an EMAT sensor. Design/methodology/approach: An EMAT (Electro Magnetic Acoustic Transducer) has been designed and fabricated with an elongated spiral coil and a permanent magnetic core. Al75×75mm and 75×100mm simulators with 2, 4, 8, 16 and 32 mm holes were produced and demonstrated that the location of the final solidification point during the continuous casting process can be monitored using a 1.0 MHz frequency. Findings: The solidification point in a continuous casting bloom could be detected through a series of tests with the use of a fabricated probe and the amplitude extent of ultrasonic wave decreases as the hole diameter of the simulators increases. Furthermore, through a test of lift-off effect it was found that the extent of amplitude decreases as lift-off increases, thus one of the most important factors for a field application. Research limitations/implications: As cutting speed and cutting length can be predicted from a miniaturization of the sensor and construction of an on-line system for a field installation, a considerable amount of time and energy can be saved by reducing mistake ratio and curtailing unnecessary processes. Originality/value: The measured ultrasonic waves allow for prediction of the casting speed necessary to correctly locate the liquid core and thereby maximize the benefits of soft reduction and the productivity of the machine.

Słowa kluczowe

PL

analiza; modelowanie; proces ciągłego odlewania; przetwornik elektromagnetyczny; temperatura krzepnięcia; pomiar temperatury

EN

analysis; modeling; continuous casting process; electromagnetic transducers; solidification point; measured temperature

• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2006
• Tom: Vol. 17, nr 1-2
• Strony: 357--360
• Opis fizyczny: Bibliogr. 15 poz., rys., wykr.

Twórcy

autor

Kim, I. S.

• Department of Mechanical Engineering, Mokpo National University, Jeonnam, 534-729, Korea,

autor

Son, J. S.

• Department of Mechanical Engineering, Mokpo National University, Jeonnam, 534-729, Korea

autor

Kim, H. J.

• Korea Institute of Industrial Technology, Chungnam, 330-820, South Korea

autor

Chin, B. A.

• Mechanical Engineering Department, Auburn University, AL, 36849-5341, USA

Bibliografia

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