Fundamental Study on New Gasketless Flange and New Gasket Using Elastic Deformation.

This paper deals with a new seal system between two flanges without using gaskets. The system includes a groove and an annular lip that is held by one of the flange with its highest point in contact with the other flange to form a seal line when the flanges are assembled. The condition whether the system leaks or not depends on the shape and dimension of the thinned area with the annular lip deformed during the contact. In this study several gasketless flanges are prepared with varing the fundamental dimensions of the flange to investigate the condition through an experimental and FEM analysis. The analysis indicates that the conditions can be expressed in terms of the maximum contact stress and the plastic zone size when the flanges are assembled.