Superconducting magnetic separators

In a magnetic separator of the type having at least one superconducting magnet coil in an evacuated cryostat housing which presents a generally vertical outer wall, means for feeding a stream containing magnetically responsive and non-responsive particles adjacent said wall, the magnetically responsive particles of said stream being drawn closer to the wall by magnetic action of said coil than the non-responsive particles, and a splitter for separating a fraction of said stream which is closer to said wall from a fraction farther from said wall,

• the improvement wherein,
• said each coil is in a generally vertical plane and has approximately straight horizontal upper and lower portions which are joined by ends,
• said outer wall is generally parallel to and closely adjacent said coil and tends to flex inwardly between said upper and lower portions when said housing is evacuated,
• insulation is provided between said coil and said outer wall,
• a vertical coil-confining member extends within the housing from below the lower portion to above the upper portion of the coil to hold said portions against vertical displacement by electromagnetic repulsion force acting on them in operation,
• transverse support means within the housing and engaging said wall between the upper and lower coil portions and holding said wall away from the coil when the housing is evacuated, so that said wall does not press said insulation against the coil,
• said transverse support means and coil-confining member passing one another within said housing without touching so that said transverse support means does not conduct heat from the wall to said coil-confining member.