Abstract: Improved rail grinding apparatus for correcting flatness errors in the slew bearings of large earthmoving machines is disclosed. The grinding apparatus includes a grinding wheel (22) rotated by a motor (24) and forced against a rail (13) by lead screws (28). The latter are controlled by means of displacement sensors (31) and associated control means (33 and 34) so as to grind a profile along the rail (13). The displacement sensors follow guide rails (29) which conform to the desired profile to be ground along the rail (13). The control means (33) may be interfaced with suitable computing means to modify the displacement of the lead screws (28) relative to the guide means (29).

Abstract: There is provided load measuring apparatus for determining loads applied to a rolling element bearing. A rolling element of such a bearing is provided with a substantially centrally disposed cavity within which is supported sensing means adapted to monitor a dimension of said cavity. When a bearing is loaded, the rolling elements will distort and the applied load is a function of the amount of distortion of the rolling elements. The load measuring apparatus is calibrated to provide the load from the output of the sensing means.