Suitable for double-sided grinding and polishing of silicon wafers, sapphire, quartz crystals, glass ceramic sheets and other hard and brittle materials. The equipment adopts independent 4 motor motion control system. The center gear, the inner ring gear and the upper and lower grinding discs are rotated according to the set rotary ratio. For the workpiece bracket fixed between the upper and lower grinding discs, the planetary gears are used for precise two-side grinding. Or polished. The lower grinding disc is carried on a high-precision oil dynamic pressure platform and is manufactured by the latest grinding technology to ensure high-precision grinding disc end jump, high rigidity parts and precision assembly to bring stable processing performance and precision.