A rotary joint for connecting a stationary body to a rotating body. The rotary joint has a rotatable wear plate connectable to the rotating body and a seal ring seated in the wear plate. A spring-biased piston engages the seal ring against the wear plate by compressed springs between an end flange and the piston. The end flange and the piston are at least partially disposed within a shroud, wherein the shroud has at least one aperture extending there through. Alignment rings are formed on the piston and viewable through the aperture in the shroud to confirm the proper distance between the end flange and the piston and the proper force applied to the piston. A seal wear indicator is connected to the piston and moves between an exposed position, wherein the seal ring is not worn, and a non-exposed position, wherein the seal ring is worn.