Low forward pressure burst-high backpressure resistant rupture disc

Abstract

A fluid pressure relief assembly for a system operating under an elevated pressure includes a support structure having means defining a bore therethrough of desired cross-sectional configuration, the support structure being provided with a shoulder extending transversely into the bore and presenting a peripheral abutment surface which divides the bore into a first zone an a second zone. The assembly further includes a bidirectional relief means having a central frangible section, and means mounting the relief means across the bore of the support structure in normal flow blocking relationship thereto. A peripheral portion of the central frangible section is disposed to engage the shoulder for support thereby. The central portion of the frangible section within the innermost margin of the shoulder is constructed to undergo rupture only when the pressue in the first zone exceeds the pressure in the second zone by a preselected first magnitude. The peripheral portion of the frangible section which engages the shoulder includes means causing the frangible section to rupture when the pressure in the second zone exceeds the pressure in the first zone by a preselected second magnitude, and means extending around a substantial part of the circumferential extent of the peripheral portion for increasing its structural integrity. A method for constructing a fluid pressure relief assembly for a system operating under an elevated pressure is also disclosed. Also disclosed is an embodiment of the invention wheren the relief means is unidirectional.