Rupture disc assembly

Abstract

Disclosed is a rupture disc assembly for use in making a temporary seal in a vessel such as a casing string. The rupture disc assembly may include a rupture disc having a side surface that has a shallow angle taper inward towards a bottom surface of the rupture disc, and a mounting apparatus to support the rupture disc so that the rupture disc forms the temporary seal. When a disc working pressure is applied to a top surface of the rupture disc, engagement/force transmission between the rupture disc and the mounting apparatus produces enough radial compression in the rupture disc due to the shallow angle taper to significantly mitigate or cancel tensile stresses thereby avoiding the rupture disc from breaking. The rupture disc may be configured to break when the rupture disc is subjected to a disc working pressure that is greater than the disc rupture pressure, thereby removing the temporary seal. An axial abutment surface feature may be provided which is configured and operable to limit downward axial movement of the rupture disc relative to said disc support mechanism and thus be operable to restrict the amount of compression said tapered wall surface of said disc support mechanism can exert on said at least a portion of said rupture disc when the top surface of the rupture disc is subjected to said hydraulic pressure within the well.