Abstract: Improved drive shafting elements suitable for use in high speed rotating crushing machinery are disclosed comprising a central cantilever shaft mounted within a surrounding sleeve to which the cantilever shaft 15 rigidly connected at one end and within which the cantilever shaft has substantial radial play at the other end to permit a rotating impeller or similar element mounted thereon to center itself automatically for rotation on its center of gravity at speeds above the first critical speed. Means are included for damping radial vibrations as the shafting rotates through the first critical speedand for damping whirl due to shaft instabilities and self-excited vibrations above the first critical speed. Improved impactor targets for use in centrifugal crushing machines and and improved centrifugal crushing method are also disclosed.

Abstract: Improved drive shafting elements suitable for use in high speed rotating crushing machinery are disclosed comprising a central cantilever shaft mounted within a surrounding sleeve to which the cantilever shaft is rigidly connected at one end and within which the cantilever shaft has substantial radial play at the other end to permit a rotating impeller or similar element mounted thereon to center itself automatically for rotation on its center of gravity at speeds above the first critical speed. Means are included for damping radial vibrations as the shafting rotates through the first critical speed and for damping whirl due to shaft instabilities and self-excited vibrations above the first critical speed. Improved impactor targets for use in centrifugal crushing machines and .[.and.]. .Iadd.an .Iaddend.improved centrifugal crushing method are also disclosed.