High-precision underground hydraulic pipe fitting butt joint device

The invention relates to a high-precision underground hydraulic pipe fitting butt joint device which comprises a mounting frame and a hydraulic cylinder mounted on the mounting frame, and further comprises a lifting plate movably arranged on the mounting frame and connected with the movable end of the hydraulic cylinder through an elastic triggering mechanism, and the two ends of the lifting plate are arranged in a circular shape; the two ends of the lifting plate are each provided with a circumferential clamping mechanism used for fixing a heat exchange tube, the two circumferential clamping mechanisms are connected with a power mechanism installed on the lifting plate, the two sliding plates are movably arranged on the lifting plate, the lifting plate is connected with lifting pushing mechanisms installed on the sliding plates, and the lifting pushing mechanisms are connected with the sliding plates. The sliding plate is provided with a thread fixing mechanism used for fixing the electric melting sleeve, th