Retaining rings are used for integral rubber flange type expansion joints and connectors to distribute the
bolting pressure evenly and prevent rubber flange damage during bolt tightening.
They are drilled to match the specification of mating pipe flange and installed behind the flange of the expansion joint. They are normally cut in half or quarter at the bolt holes to ensure proper seal at all points when bolts are tightened. Metal washers are used where the rings are split.
Kurbo's normal retaining ring material is hot-dipped galvanized carbon steel for corrosion resistance. Stainless and other materials available as material selection varies due to environmental conditions.