Automatically-adjusted centering device

The utility model relates to an automatically-adjusted centering device, and belongs to the technical field of drilling equipment. The clamp comprises a clamp body, a positioning block and limiting mechanisms, the positioning block is movably mounted in the middle of the clamp body, the limiting mechanisms are symmetrically arranged on the clamp body on two sides of the positioning block, each limiting mechanism comprises a guide plate, a connecting plate and a compression spring, the connecting plate is movably inserted into the clamp body, the guide plate is fixedly mounted on one side of the connecting plate, and the compression spring is fixedly mounted on the other side of the connecting plate. And a compression spring is arranged between the other side of the connecting plate and the clamp body. The roller shaft on the guide plate is in contact with the tubular column, so that the friction force between the guide plate and the tubular column is effectively reduced, and the service life of the guide plat