Patent ID: 8789582
Filing Date: 2014-07-29
Classification: E21B

Abstract:
1. A method for regulating flow of a fluid during primary cementing of a subterranean well, the fluid having a fluid-flow rate, and the well having a borehole and at least one casing string, comprising: (i) circulating a process fluid through the casing interior and into an annular region outside the casing; (ii) launching into the casing interior an apparatus for regulating fluid flow, the apparatus comprising: (a) a cementing plug fitted with at least one membrane; (b) an adjustable one-way valve incorporated inside the plug interior; and (c) a releasable device inside the plug interior, wherein the device is a ball that is expelled from the plug; (iii) continuing to pump process fluid until the apparatus reaches and becomes lodged at the end of the casing string; and (iv) continuing to pump process fluid until the plug membrane ruptures, thereby allowing process fluid to enter the plug interior.