(1) Big gears need to be pre-grinded after carburizing treatment, in order to eliminate heat treatment deformation before machining locating pin hole of large gears, so that the reference teeth will be in the correct position during subsequent machining locating pin hole.
(2) The angular position error of the center line of the reference teeth and the center line of the positioning pin hole is not more than 0.003 degrees, which is calculated according to the indexing circle diameter of 882 mm. The position error of the center line of the reference teeth and the center line of the groove is not more than 0.023 mm.As shown in the figure.
(3) The turning and milling machining center with on-line measuring mechanism is needed for locating pin hole. First, the center position (angular position) of the reference teeth of the large gear is found out with the probe of the on-line measuring device and recorded; then, the recorded angular position is used for cutting, and the locating pin hole is machined according to the drawing requirements by drilling and boring method, and the marking is made on the reference teeth.
(4) The machined locating pin hole needs to measure whether the angular position is correct or not. It can be measured online on the machine tool or offline on the three coordinates.