Performance Evaluation of Hydraulic and Magnetic Clamp Crane for Transporting Curved Steel Plate for Shipbuilding, with Permanent Magnet Applied

영구자석을 적용한 선박용 곡면 철판 이송용 유압식 마그네틱 클램프 이송장치의 성능평가에 대한 고찰

Moon, Byung Young;Lee, Sung Bum;Lee, Ki Yeol

  • Received : 2015.06.09
  • Accepted : 2015.08.19
  • Published : 2015.08.31


As a new technical approach, a hydraulic and magnetic clamp device was developed to realize a magnetic clamp crane system by simultaneously actuating eight individual hydraulic cylinders. In this approach, an Sr-type of ferritic permanent magnet (SrO· 6Fe2O3), rather than the previous electromagnet, was utilized for the purpose of lifting and transporting the large curved steel plates used for manufacturing ships. This study had the goal of developing and manufacturing a hydraulic, magnetic clamp prototype composed of three main parts, including the base frame, cylinder joint, and magnet joint, in order to safely transport curved steel plates. Furthermore, this research included a performance evaluation of the manufactured prototype and acquired the purposed quantity value in the performance test. The most significant item, the magnetic adhesive force (G), was evaluated in a performance test, which utilized a ferritic permanent magnet (Sr type) with 3700~4000 G of residual induction (Br) and 2640/2770 Oe of coercive force (Hc). In particular, relevant items such as the hoist tension (kN), transportation time (s), and applied load (Kgf) on the hydraulic cylinders were also evaluated in order to determine the optimum values.


Hydraulic and magnetic clamp;Curved steel plates;Performance evaluation;Ferritic permanent magnet;Residual Induction;Coercive force;Adhesive force


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