We designed and constructed a eryocooler cooled 5 T superconducting magnet with a horizontal room temperature bore of 50 mm and a vertical room temperature bore of 90 mm without liquid helium. The magnet, which is directly cooled by 4 K Gifford-McMahon cryocooler in vacuum, consists of NbTi coil, Bi(2223) bulk current leads and cryostat. The coil with an inner diameter of 130 mm, an outer diameter of 301 mm, a height of 66 mm and a gap of 80 mm is made using NbTi wires and Cu-plated SUS bobbin. Bi(2223) bulk current leads are thin-walled sintered cylindrical tube. The outer diameter, height and weight of the magnet are 510 mm, 730 mm and 260 kg, respectively. The magnet is cooled down to 3.8K in approximately 62 hours. A continuous operation at 5 T, which is generated by an operating current of 122 A, has been performed.
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