A shaft seal includes first and second rings, each formed from first and second discrete arc segments, mounted on a shaft. The first ring includes a central opening and a flange projecting axially away from a first axial surface of the first ring around the central opening, and the flange has a radially outer surface. The second ring has a radial inner face defining a central opening that includes a first portion extending from a first axial face of the second ring and a second portion extending from a second axial face of the second ring, and the second ring is mounted to the first ring with the second portion in contact with the radially outer surface of the flange. A plurality of fasteners extend from the second ring into an axial surface of the first ring or from the first ring into an axial face of the second ring.