Abstract: Improved casing strings, and methods of using improved casing strings in subterranean cementing operations, are provided. An example of an apparatus is a pipe string comprising at least one pipe section and a delivery system of an activator. Another example of an apparatus is a pipe string comprising at least one pipe section and a delivery system of a set retarder. An example of a method is a method of cementing in a subterranean formation. Other examples of methods are methods of cementing in a subterranean formation comprising a well bore.

Abstract: Methods and systems for reverse-circulation cementing in subterranean formations are provided. An example of a method is a method of cementing casing in a subterranean well bore, comprising inserting a casing into the well bore, the casing comprising a casing shoe; equipping the casing with a well head, and a casing inner diameter pressure indicator; flowing an equilibrium fluid into the well bore; flowing a cement composition into the well bore after the equilibrium fluid; determining from the well-bore pressure indicator when the well bore pressure has reached a desired value; discontinuing the flow of cement composition into the well bore upon determining that the well bore pressure has reached a desired value; and permitting the cement composition to set in the subterranean formation. Examples of systems include systems for cementing casing in a well bore.

Abstract: Methods and systems for cementing casing in well bores drilled in subterranean formations, and more particularly, methods and systems for cementing casing in a well bore without surface casing or a well head are provided. A method provided herein may comprise sealing an annulus at the mouth of the well bore with a seal; pumping a cement composition into the annulus through the seal; and taking circulation fluid returns from the inner diameter of the casing. A system provided herein may comprise a seal of an annulus at the mouth of the well bore; a cement composition pump fluidly connected to the annulus through the seal; and a coupling connected to the exposed end of the casing for taking circulation fluid returns from the inner diameter of the casing.

Abstract: Improved casing strings, and methods of using improved casing strings in subterranean operations, are provided. An example of a method is a method of cementing a pipe string in a subterranean formation. Another example of a method is a method of cementing a pipe string in a well bore. An example of an apparatus is an improved pipe string comprising at least one pipe section; and a delivery system of an activator; wherein the delivery system of an activator is disposed adjacent an outer surface of the at least one pipe section.

Abstract: A method of initiating fluid circulation in a well bore through a casing inner diameter and an annulus outside the casing, the method having the following steps: inducing an increase in the annulus fluid pressure; flowing cement composition into the annulus at the top of the well bore; maintaining a difference in pressure between the fluid pressure of the casing inner diameter and the fluid pressure of the annulus until enough cement composition has entered the annulus to drive fluid circulation by the added cement composition weight.

Abstract: Methods and apparatus for preventing or limiting the rotation of downhole tools, such as cementing plugs, in a casing string during drillout. The apparatus includes an outer case and a radially expandable sleeve disposed therein. The sleeves will engage cementing plugs received therein. The sleeves radially expand when cementing plugs are received therein to grippingly engage the outer case and prevent or limit rotation thereof during drillout.

Abstract: An apparatus for preventing or limiting the rotation of cementing plugs in a casing string during drillout. The apparatus includes an outer housing with a sleeve disposed therein. The sleeve has an inner surface configured to engage cementing plugs received therein to cause an interference fit. The sleeve will hold the cementing plugs when rotational forces, such as drilling forces, are applied so that during drillout, rotation of the cementing plug is prevented or is at least limited.

Abstract: An apparatus for preventing or limiting the rotation of cementing plugs in a casing string during drillout. The apparatus includes an outer housing with a sleeve disposed therein. The sleeve has an inner surface configured to engage cementing plugs received therein to cause an interference fit. The sleeve will hold the cementing plugs when rotational forces, such as drilling forces, are applied so that during drillout, rotation of the cementing plug is prevented or is at least limited.

Abstract: An apparatus for preventing or limiting the rotation of cementing plugs in a casing string during drillout. The apparatus includes an outer housing with a sleeve disposed therein. The sleeve has an inner surface configured to engage cementing plugs received therein to cause an interference fit. The sleeve will hold the cementing plugs when rotational forces, such as drilling forces, are applied so that during drillout, rotation of the cementing plug is prevented or is at least limited.

Abstract: A screen provides increased erosion resistance and collapse resistance without uneconomical overcompensation and without requiring an increase in the screen's outer diameter. In a preferred embodiment, a sand control screen has a support material radially between a tubular base pipe and a filtering portion. The support material radially outwardly supports the filtering portion to help prevent radially inward collapse of the filtering portion. In another preferred embodiment, a screen has a coating applied to a filtering portion's exterior surface. The coating may alternatively or combinatively provide erosion resistance, radially inwardly retain a support material, and selectively vary flow through the filtering portion.

Abstract: A method and apparatus for use in setting sidetrack plugs in a well bore. The apparatus comprises an inflation packer assembly which may be attached to the lower end of the tubing string. The packer is inflated to seal against the well bore at the lower end of the sidetrack plug. The inflation packer is attached to a tubing string with a length of tail pipe. The tail pipe is releasably attached to the tubing string. After the inflation packer is sealed against the well bore, a cementitious fluid is circulated above the bladder to form the sidetrack plug. The tailpipe is then released and the tail pipe and the inflation packer remain in the hole and form a part of the sidetrack plug. An additional embodiment includes a whipstock connected to the inflation packer assembly.

Abstract: A method of forming a kickoff plug in a borehole is disclosed. The method includes a first phase in which the interval to be cemented is treated to remove gelled mud and mud cake from the walls of the borehole and in which drilling fluid is conditioned for subsequent cementing operations. The method includes a second phase in which a hydrostatically balanced plug of a hydraulic cement slurry is placed in the interval to be cemented and then permitted to harden to form the kickoff plug. Each phase of the method features the injection of high velocity streams of fluid, e.g. drilling fluid and cement slurry, into the borehole in a plane or planes which are substantially parallel to the cross section of the borehole and at linear velocities sufficient to cause circulation of gelled mud, mud cake, and drilling cutting from the borehole.

Abstract: A casing packer apparatus includes a mandrel having a mandrel exterior, a longitudinal mandrel bore defined therethrough, and a power port defined in the mandrel communicating the mandrel bore with the mandrel exterior. A packer element is concentrically received about the mandrel. An annular piston is concentrically received about the mandrel and has an annular differential pressure area defined thereon and communicated with the mandrel bore through the power port. The annular piston and packer element are operably associated so that the packer element is set by sliding motion of the piston in response to increased fluid pressure in the mandrel bore. Either a compression set packer element or an inflatable packer element may be utilized.

Abstract: The present invention provides an apparatus for casing a well. The inventive apparatus comprises: an outer casing; an inner casing positionable inside the outer casing; and a squeeze packer assembly incorporatable in the inner casing. The squeeze packer assembly is mechanically operable for sealing the annulus between the inner casing and the outer casing.The present invention also provides a method of installing an inner casing inside an outer casing. The inventive method comprises the steps of: (a) incorporating a mechanically operable squeeze packer assembly in the inner casing and (b) inserting the inner casing into the outer casing.