1. Adjustment transposition method: change the direction of the worn gear and continue to use the gear that is not worn or slightly worn.
2. Displacement cutting method: turn the scrapped big gear outer diameter to remove the corresponding value, and then roll the gear again to remove the corroded part of the tooth surface. The big gear has negative displacement and the small gear has positive displacement.
3. Tooth inlay repair method: For gears with low load and low rotation speed, in the repair process, the trapezoidal groove at the root of the bad gear is planed on the planer, and the new gear blank with the same groove shape is pressed in, welded firmly or fixed with bolts, and processed and formed.