Characteristics of AC Surface Spark Voltage of Pipes Composed with High Strength Polyethylene Fiber Reinforced Plastics in Coolant

摘要

High strength polyethylene fiber reinforced plastics (DFRP's) have large negative thermal expansion coefficients. Then they are suitable for bobbins for superconducting magnets of AC use. One of the most important problems on AC magnets is insulation property of bobbins and coolant such as Liq.N_2 or Liq.He. We carried out some experiments of surface spark voltages of DFRP's and GFRP's generally used for the bobbins. The experimental results show that DFRP is suitable for bobbins for AC superconducting magnets.