Tubular object under-mud cutting device

The invention relates to the technical field of marine mechanical equipment, in particular to a tubular object under-mud cutting device which comprises a tubular object fixing frame, a plurality of hoops for tightly holding a tubular object are arranged on one side of the tubular object fixing frame, and a cutting guide frame is rotationally connected to the other side of the lower portion of the tubular object fixing frame. A first hydraulic cylinder connected with the cutting guide frame is arranged in the tubular object fixing frame and controls the cutting guide frame to rotate around the tubular object fixing frame. A U-shaped cutting frame is arranged in a side frame of the cutting guide frame, a second hydraulic cylinder connected with the U-shaped cutting frame is arranged in the cutting guide frame, a rope saw guide wheel is arranged at the lower end of the U-shaped cutting frame, and a rope saw for cutting tubular objects is arranged on the rope saw guide wheel. In the cutting process, the number of