Ultrasonic thickness gauge for pipeline detection

The utility model relates to the technical field of pipeline measurement, and discloses an ultrasonic thickness gauge used for pipeline detection, which comprises an instrument body, and a connector is arranged at the top end of the instrument body; the fixing mechanism is arranged at the top end of the instrument body, and the fixing mechanism comprises a fixing groove. The fixing groove is formed in the top end of the instrument body, then the rotating rod can be rotated to drive the moving plate to ascend, the moving plate drives the connecting rod to move in the moving groove, when the connecting rod moves, the first moving block is pushed to move on the surface of the limiting rod, and the first moving block drives the fixing block to move; and then the fixing block enters the fixing groove, so that the connector is fixed through the fixing block, the use stability and the working efficiency of the instrument are improved, and the situation that the connector is far away from the top end of the instrumen