b'Ball Bearing ComponentsNCH ISelection Bushing and Ball CageChartOperating Condition Selection ChartType I Type IIaContinuous Preload Preload Partially RelievedType IIb Type IIIPreload Relieved DisengagedCaution: Be sure bushing does not strike punch holder or demountable pin clamping screw atminimum shut height. If this condition exists, use a shorter bushing and corresponding ball cage.18'