Detection pin assembly

A detection pin assembly disclosed by the present invention comprises a detection tool support, a lineation pin and a center pin, the detection tool support is provided with a mounting hole along the longitudinal direction in a penetrating manner, the lineation pin is slidably arranged in the mounting hole in a penetrating manner and can rotate around the axial direction of the mounting hole, the lineation pin is provided with a guide hole coaxial with the mounting hole in a penetrating manner, and the center pin is slidably arranged in the guide hole in a penetrating manner and can rotate around the axial direction of the guide hole. The center pin is provided with a detection end extending out of the two ends of the guide hole and a handle end, the detection end comprises a first detection section and a second detection section which are sequentially arranged in the direction away from the handle end, and the center pin slides in the guide hole till the first detection section extends out of the guide hole