Abstract: Systems and methods for activating a down hole tool in a wellbore. A piston is moveable from a first position to a second position for activating the down hole tool. The piston includes a first side exposed to an activation chamber, and a second side operatively coupled to the down hole tool. A rupture member has a first side exposed to the activation chamber and a second side exposed to the interior of a base pipe. The rupture member is configured to rupture when a pressure differential between the activation chamber and the interior reaches a predetermined threshold value, at which point the rupture member allows fluid communication between the interior and the activation chamber to pressurize the activation chamber and move the piston, thereby activating the down hole tool.

Abstract: Systems and methods for activating a down hole tool in a wellbore. A piston is moveable from a first position to a second position for activating the down hole tool. The piston includes a first side exposed to an activation chamber, and a second side operatively coupled to the down hole tool. A rupture member has a first side exposed to the activation chamber and a second side exposed to the interior of a base pipe. The rupture member is configured to rupture when a pressure differential between the activation chamber and the interior reaches a predetermined threshold value, at which point the rupture member allows fluid communication between the interior and the activation chamber to pressurize the activation chamber and move the piston, thereby activating the down hole tool.

Abstract: An apparatus for indicating the orientation of a structure which includes an orienting sub releasably connected at an outer case. The orienting sub is at a preselected orientation relative to the structure. A change in fluid pressure of a predetermined magnitude of flow rate through the orienting sub will indicate that the structure is at a desired orientation in the well.

Abstract: An apparatus for indicating the orientation of a structure which includes an orienting sub releasably connected at an outer case. The orienting sub is at a preselected orientation relative to the structure. A change in fluid pressure of a predetermined magnitude of flow rate through the orienting sub will indicate that the structure is at a desired orientation in the well.

Abstract: Methods and apparatus for subterranean well bore operations. An exemplary embodiment of a method is a method of activating a device in a subterranean well bore, the device having a baffle adapter configured to achieve sealing contact with a cementing plug, the cementing plug having an outer body and a detachable inner mandrel attached to the outer body, including the steps of: displacing the cementing plug into contact with the baffle adapter so that the outer body of the cementing plug achieves sealing contact with the baffle adapter; and applying a differential pressure across the cementing plug, thereby activating the device. An exemplary embodiment of an apparatus is a baffle adapter, having an inner bore designed to engage and seal against the outer body of a plug.

Abstract: A dart may include a foam body, a filtering material at least partially covering the foam body, and a mandrel. The foam body may surround the mandrel.

Abstract: A dart may include a foam body, a filtering material at least partially covering the foam body, and a mandrel. The foam body may surround the mandrel.

Abstract: A method of cementing a casing string in a subterranean well bore. An exemplary embodiment of a method includes injecting a cement composition into a casing string, and deploying within the casing string at least one cementing plug having an outer body and a detachable inner mandrel attached to the outer body.

Abstract: Methods and apparatus for subterranean well bore operations. An exemplary embodiment of a method is a method of activating a device in a subterranean well bore, the device having a baffle adapter configured to achieve sealing contact with a cementing plug, the cementing plug having an outer body and a detachable inner mandrel attached to the outer body, including the steps of: displacing the cementing plug into contact with the baffle adapter so that the outer body of the cementing plug achieves sealing contact with the baffle adapter; and applying a differential pressure across the cementing plug, thereby activating the device. An exemplary embodiment of an apparatus is a baffle adapter, having an inner bore designed to engage and seal against the outer body of a plug.

Abstract: Methods and devices useful in stage cementing operations are provided. One example of an apparatus may comprise a catcher tube assembly and a deformable device. One example of a method is a method of stage cementing a casing string comprising: positioning a catcher tube on top of a float collar; pumping a first fluid through the casing string; placing a first deformable device in the casing string; and pumping a second fluid through the casing string, thereby causing the first deformable device to translate downward in the casing string and into the catcher tube.

Abstract: A method of cementing a casing string in a subterranean well bore is provided. An exemplary embodiment of a method includes injecting a cement composition into a casing string, and deploying within the casing string at least one cementing plug having an outer body and a detachable inner mandrel attached to the outer body.

Abstract: Methods and apparatus for subterranean well bore operations are provided. An exemplary embodiment of a method of the present invention is a method of activating a device in a subterranean well bore, the device having a baffle adapter configured to achieve sealing contact with a cementing plug, the cementing plug having an outer body and a detachable inner mandrel attached to the outer body, including the steps of: displacing the cementing plug into contact with the baffle adapter so that the outer body of the cementing plug achieves sealing contact with the baffle adapter; and applying a differential pressure across the cementing plug, thereby activating the device. An exemplary embodiment of an apparatus of the present invention is a baffle adapter, having an inner bore designed to engage and seal against the outer body of a plug.

Abstract: Zonal isolation of well bores is often desirable for performing downhole operations such as stimulation operations. In certain embodiments, diverter plugs for achieving zonal isolation in a casing string in a well bore may comprise a mandrel having a first end and a second end; a compressible body attached to and surrounding a longitudinal portion of the mandrel; and a sealing nose attached to the first end of the mandrel. In certain embodiments, systems for achieving zonal isolation of a casing string in a well bore may comprise a diverter plug comprising a mandrel having a first end and a second end, a compressible body attached to and surrounding a longitudinal portion of the mandrel, and a sealing nose attached to the first end of the mandrel; and a landing collar sized to mate with a portion of the sealing nose of the diverter plug. Associated methods are also provided.

Abstract: Zonal isolation of well bores is often desirable for performing downhole operations such as stimulation operations. In certain embodiments, diverter plugs for achieving zonal isolation in a casing string in a well bore may comprise a mandrel having a first end and a second end; a compressible body attached to and surrounding a longitudinal portion of the mandrel; and a sealing nose attached to the first end of the mandrel. In certain embodiments, systems for achieving zonal isolation of a casing string in a well bore may comprise a diverter plug comprising a mandrel having a first end and a second end, a compressible body attached to and surrounding a longitudinal portion of the mandrel, and a sealing nose attached to the first end of the mandrel; and a landing collar sized to mate with a portion of the sealing nose of the diverter plug. Associated methods are also provided.

Abstract: A regulating valve assembly for regulating fluid flow through a passage, the assembly having: a back-flow valve comprising a seat and a closure element, wherein the closure element engages with the seat in a closed configuration and disengages from the seat in an open configuration; a lock in mechanical communication with the back-flow valve to lock the backflow valve in the open configuration; and a forward-flow valve in mechanical communication with the lock and comprising a seat and a closure element, wherein the closure element engages with the seat in a closed configuration and disengages from the seat in an open configuration.

Abstract: A method for controlling a fluid pressure applied to a cementing plug comprises disposing the cementing plug within a casing string to define a trapped volume of fluid within the casing string, isolating a portion of the trapped volume of fluid adjacent the cementing plug to define an isolated volume of fluid, and relieving the fluid pressure within the isolated volume of fluid at a first rate sufficient to prevent damage to or inadvertent release of the cementing plug. An apparatus for relieving fluid pressure within a casing string being run into a well bore comprises at least one equalizer valve connected to a work string extending into the casing string, and a sealing device disposed above the equalizer valve to seal an annular space formed between the work string and the casing string.

Abstract: The present invention relates to subterranean cementing operations, and more particularly to an apparatus useful in loading cementing plugs and darts into tubulars, and methods of using such apparatus in subterranean cementing operations. An example of a method of the present invention is a method of placing a compressible object having a cross-section within a tubular, including the steps of: reducing the cross-section of the compressible object; placing the compressible object with the reduced cross-section in a tubular; and releasing the compressible object within the tubular. Another example of a method of the present invention is a method of reducing the radial cross-section of a compressible object. Other examples of apparatus of the present invention include apparatus for placing a compressible object into a tubular.

Abstract: The present invention relates generally to subterranean well construction, and more particularly, to improved darts and methods of using these darts in subterranean wells. In one embodiment, the present invention provides a dart for activating a plug located within a subterranean well bore, the dart comprising a mandrel, and a foam body attached to the mandrel. Optionally, an elastic tether can be included, inter alia, to absorb the deformation of the foam body.

Abstract: The present invention provides plugs, plug systems and methods for using these plugs and systems in subterranean wells. An example of a system of the present invention is a plug system for separating fluids successively introduced into a passage comprising: an assembly comprising a plurality of plugs, wherein at least one plug comprises an outer body and a detachable inner mandrel attached to the outer body; and wherein the plurality of plugs are releasably attached to each other.

Abstract: The present invention is directed to plugs, plug systems and methods for using the plugs and systems in subterranean wells. The plugs comprise an inner mandrel and an outer sleeve formed of a compressible foam. The plug systems include an assembly comprising a top plug and a bottom plug having foam outer sleeves. The plug systems further comprise a float valve into which the assembly fits. In the method, the bottom plug is deployed ahead of the top plug to separate a second fluid from a first fluid and wipe the inside of the pipe string clean of the first fluid. The top plug is used to wipe the inside of the pipe string clean of the second fluid and stop the displacement of the second fluid into the annulus between the casing string and the well bore.