Deep buried pipeline low-disturbance cutting and discarding equipment and construction method

The invention discloses a deeply buried pipeline low-disturbance cutting and discarding device and a construction method, and the device comprises a shell which is erected on the ground and is internally provided with a vertical slide way; the right-angle supports are arranged on the two sides of the shell and used for supporting the shell. The cut-off support is arranged in the vertical slide way and used for aligning the deeply-buried pipeline, the cut-off support comprises a pipe fitting, the pipe fitting is arranged in the vertical slide way in a sliding mode and provided with a movable cavity, and a plurality of sets of positioning grooves are sequentially formed in the inner wall of the movable cavity in the pipe diameter direction of the deeply-buried pipeline; the multiple groups of circular pipes are arranged in the movable chamber in a straight line; the horizontal length of the spliced round pipes is larger than the pipe diameter of the deeply-buried pipeline. The static pressure device is arranged