Self-aligning valve element

The invention relates to a self-aligning valve element. The self-aligning valve element comprises a valve element rod (5) and a spherical valve element (1) which are connected, wherein a rod head end spherical surface and a back end spherical surface are arranged on a valve element head (3) of the valve element rod (5). The self-aligning valve element is characterized in that a spherical top plate (2) is fixedly installed in a valve element groove in the back surface of the spherical valve element (1); the rod head end spherical surface of the valve element head (3) stretches in the valve element groove; and the top end of the rod head end spherical surface of the valve element head (3) contacts with the spherical top plate (2), and a gap is left between the side end of the rod head end spherical surface and the valve element groove. A trial proves that after using a three-spherical surface contact structure of the self-aligning valve element disclosed by the invention, the valve element rod and the spherical top plate are capable of carrying out relative circumferential rotation, and the valve element and a valve seat are also capable of realizing a transversal movement of the valve element head due to a thrust of an execution mechanism during contact of the valve element and the valve seat, thus greatly increasing the adjustable range of the valve element head.