Opening aligning device for welding large-diameter pipeline

The utility model discloses an aligning device for welding a large-diameter pipeline, which relates to the technical field of pipeline connection and comprises two large support frames, each large support frame is provided with a support I, each support I is provided with a circular-arc-shaped mounting groove for placing a large-diameter circular pipe, the two circular-arc-shaped mounting grooves are concentrically arranged, and the two circular-arc-shaped mounting grooves are arranged in parallel. A lead screw is installed between the two large supporting frames, the lead screw is connected with a sliding block through threads, the lead screw can rotate in the axial direction, a second support used for containing large-diameter round pipes is arranged on the upper portion of the sliding block, and a supporting assembly used for supporting the inner wall of each large-diameter round pipe is arranged in each large-diameter round pipe. The driving motor and the speed reducer drive the lead screw to rotate, so t