Abstract: Jack-up drilling platform lifting device equipment (TYPE:D60H) is imported from NOV (made by BLM), which has been used for many years, and consequently the gearbox gear is worn. In order to achieve the independent repair and manufacture of imported equipments, we explored the inspection and repair of gearbox gears. Through inspection and repair construction, gear parameter measurement, analysis and calculation of gear parameters, the technical parameters of the gearbox gears are determined, which fills the gap of the technology. It provides a basis for the independent repair and manufacture of equipment, and lays a foundation for the localization and standardization of the imported equipments.