Fike Corporation

Jeffrey A Stokes

Eddie R Malcolm

Donald R Hibler, Jr

Gene Hill

Lindsey Lee

A cementing tool () capable of being installed in a casing string () and configured to selectively permit the flow of cement through one or more ports () in the tool is provided. The ports () are normally sealed by rupture disc assemblies () comprising a rupture disc () that can be opened to permit flow of cement through the casing string central bore () and into the annulus () defined by the casing string () and the downhole formation (). The cementing tool () is particularly useful during cementing operations in which the annulus () has become blocked by a collapsed portion of the formation by allowing the obstruction () to be bypassed and the flow of cement () into the annulus to be continued without substantial interruption. Tool () may also be used in multistage cementing operations.

Method and apparatus for cementing a wellbore

An activation rupture disc unit is provided that is capable of withstanding a substantially higher back pressure than its burst activation pressure. The unit includes a tubular housing having a fluid passage. Tapered wall structure defines at least a portion of the passage with the fluid outlet thereof being of greater area than the fluid inlet. A rupture disc is carried by the housing and has a central bulged section in fluid-blocking relationship to the passage. A tapered, self-releasing solid plug is positioned in and conforms to the tapered portion of the passage. The plug has a curved surface conforming to and positioned in full supporting relationship to the central section of the rupture disc. The plug is of sufficient mass to prevent rupture of the central section of the disc under a back pressure substantially greater than the activation pressure of the disc.

Growing community of inventors

Grain Valley, MO, United States of America

Jeffrey A Stokes