Clamping device for rotating table

According to the clamping device for the rotating table, the rotating table comprises a table body, a gear ring fixedly connected to the lower portion of the table body and a sliding seat body rotationally connected to the table body and located below the gear ring, the clamping device comprises a plurality of clamping assemblies evenly distributed in the circumferential direction of the gear ring, and each clamping assembly comprises a clamping block, a clamping block and a clamping block, one end of the clamping block is connected to the sliding seat body, and the other end is arranged on the upper end face of the gear ring; the first piston is slidably connected to the lower end face of the other end of the clamping block in the vertical direction; the second piston is slidably connected to the upper end face of the sliding seat body in the vertical direction, and the second piston is axially aligned with the first piston; the oil way communicates with the first piston and the second piston so as to drive