Model Testing of an Oval-Shaped Seal for Sealing of Large Gaps Between Mating Surfaces

A pressure chamber was designed and manufactured in two parts, which were clamped together at their flanges using a clamping ring. An "O" ring seal was used for sealing the gap between the mating surfaces. The clamping ring held the two flanges together while the chamber was pressurized with mixed gas. The internal chamber pressure caused the gap to widen (unseat with pressure), resulting in a final gap in which the O-ring could no longer maintain an adequate seal. The O-ring seal groove was designed with an undercut or dove-tail groove to capture the O-ring. The dovetail groove cross-sectional area was designed to accept 100 percent of the O-ring area. The pressure chamber could not be taken out of service to redesign the mating connection and to accomplish the related production work. To solve this problem, an oval-shaped seal was designed to fit into the existing dovetail groove, but with a greater standoff height to allow for the larger gap (Fig. 1).Fig. 1Pressure chamber assembly