A carrier head for supporting a workpiece is provided. The carrier head comprises a mount plate having an aperture therethrough, and a clamp ring having a foot portion and a first leg portion extending therefrom. The first leg portion extends through the aperture, and the foot portion abuts the mount plate proximate the aperture. A flexible bladder has first and second ribs that are received between the mount plate and the foot portion. An annular fastener is removably coupled to the leg portion, and engages the mount plate to cause the first and second ribs to be sealingly secured between the mount plate and the foot portion.