Necking well ring of well hole of inspection well

The utility model relates to a necking well ring of a well hole of an inspection well, comprising the well hole, a well seat and a connecting pipe piece, wherein the well hole is fixed at the top part of the well seat; the connecting pipe piece penetrates through the well head and is fixedly connected with the well seat; the inner wall of the well hole is provided with a around the well hole; the upper part of the well hole is provided with a necking section; and the outer side of the necking section is provided with the necking well ring. In the necking well ring, the structure is simple and reasonable, the fracture caused by extrusion of the necking section of the well hole is effectively prevented by adding the necking well ring, and the necking well ring is movably connected with the well hole, so that the operation is also convenient and the time is saved.