Ring stiffness inner diameter positioning device for engineering detection

The utility model relates to the technical field of engineering detection, and particularly discloses a ring stiffness inner diameter positioning device for engineering detection, which comprises a base and two inner positioning mechanisms, each inner positioning mechanism comprises a positioning motor, a positioning threaded rod, a cuboid positioning cylinder and an inner positioning shaft, two power grooves, a positioning groove and a positioning opening are formed in the top face of the base, the positioning groove communicates with the positioning opening and the two power grooves, the two positioning motors are fixed into the two power grooves correspondingly, one ends of the two positioning threaded rods are fixedly connected with motor shafts of the positioning motors, and the other ends of the two positioning threaded rods are in threaded connection with the positioning cylinder. The two positioning cylinders slide in the positioning groove and abut against the two opposite side faces of the positioni