Abstract: A positive displacement motor (PDM) is provided comprising an outer housing, a thermoplastic stator and a rotor. The PDM may additionally include a mechanism that allows the stator to be removable from the PDM when the PDM is not in operation and resists rotational movement of the stator with reference to a longitudinal axis of the stator and axial movement of the stator along the longitudinal axis of the stator when the PDM is operating, and a rotor disposed within the stator and configured to rotate within the stator when a fluid flows through the stator.

Abstract: A positive displacement motor (PDM) is provided comprising an outer housing, a thermoplastic stator and a rotor. The PDM may additionally include a mechanism that allows the stator to be removable from the PDM when the PDM is not in operation and resists rotational movement of the stator with reference to a longitudinal axis of the stator and axial movement of the stator along the longitudinal axis of the stator when the PDM is operating, and a rotor disposed within the stator and configured to rotate within the stator when a fluid flows through the stator.

Abstract: A plug release apparatus for use in a well bore, the apparatus having a canister, a liner plug, and a sub. The liner plug may be releasably attached to the canister via a first release mechanism. The sub may be releasably attached to the canister via a second release mechanism. The first release mechanism may be configured to release the liner plug from the canister at a first pressure and the second release mechanism may be configured to release the canister from the sub at a second pressure.

Abstract: A method of sealing an annulus formed between a casing string and a surface in a well may include: positioning a seal element in the annulus with a swellable material of the seal element positioned between the casing string and the surface; and flowing cement through a channel formed between the swellable material and the casing string. A method of sealing in a well may include the steps of: positioning an annular seal element in the well, wherein the element may include a swellable material; and flowing cement into at least one channel formed longitudinally through the seal element. A method of sealing an annulus between two casing strings may include: providing multiple arcuate segments that may include a swellable material; and installing the segments in the annulus, wherein each of the segments may occupy a respective circumferential portion of the annulus.

Abstract: A valve system for cementing including a valve and a sleeve shifter. The valve may have a moveable sleeve with openings and a housing situated about the moveable sleeve and having flow passages. The sleeve shifter may be configured to be opened and/or closed multiple times. The valve may be used in reverse cementing and/or squeeze jobs.

Abstract: A method of sealing an annulus formed between a casing string and a surface in a well includes: positioning a seal element in the annulus, a swellable material of the seal element being positioned between the casing string and the surface; and flowing cement through a channel formed between the swellable material and the casing string. A method of sealing in a well includes the steps of: positioning an annular seal element comprising a swellable material in the well; and flowing cement into at least one channel formed longitudinally through the seal element. A method of sealing an annulus between two casing strings includes: providing multiple arcuate segments, each of the segments comprising a swellable material; and installing the segments in the annulus, each of the segments thereby occupying a respective circumferential portion of the annulus.

Abstract: A method of sealing an annulus formed between a casing string and a surface in a well includes: positioning a seal element in the annulus, a swellable material of the seal element being positioned between the casing string and the surface; and flowing cement through a channel formed between the swellable material and the casing string. A method of sealing in a well includes the steps of: positioning an annular seal element comprising a swellable material in the well; and flowing cement into at least one channel formed longitudinally through the seal element. A method of sealing an annulus between two casing strings includes: providing multiple arcuate segments, each of the segments comprising a swellable material; and installing the segments in the annulus, each of the segments thereby occupying a respective circumferential portion of the annulus.

Abstract: A method of sealing an annulus formed between a casing string and a surface in a well includes: positioning a seal element in the annulus, a swellable material of the seal element being positioned between the casing string and the surface; and flowing cement through a channel formed between the swellable material and the casing string. A method of sealing in a well includes the steps of: positioning an annular seal element comprising a swellable material in the well; and flowing cement into at least one channel formed longitudinally through the seal element. A method of sealing an annulus between two casing strings includes: providing multiple arcuate segments, each of the segments comprising a swellable material; and installing the segments in the annulus, each of the segments thereby occupying a respective circumferential portion of the annulus.

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 valve system for cementing including a valve and a sleeve shifter. The valve may have a moveable sleeve with openings and a housing situated about the moveable sleeve and having flow passages. The sleeve shifter may be configured to actuate the valve by moving the sleeve. The valve may be configured to be opened and/or closed multiple times. The valve may be used in reverse cementing and/or squeeze jobs.

Abstract: A plug release apparatus for use in a well bore, the apparatus having a canister, a liner plug, and a sub. The liner plug may be releasably attached to the canister via a first release mechanism. The sub may be releasably attached to the canister via a second release mechanism. The first release mechanism may be configured to release the liner plug from the canister at a first pressure and the second release mechanism may be configured to release the canister from the sub at a second pressure.

Abstract: A method for bonding a well bore to a casing may include several steps. Casing may be introduced into the well bore and pulses of fluid may be directed from within the casing into the well bore. An annulus between an inner surface of the well bore and an outer surface of the casing may be filled with fluid. A method for reducing fluid or gas migration into a fluid in the annulus may include inducing pressure pulses in the fluid before the fluid has cured.

Abstract: Methods for cleaning or stimulating a well include providing an isolation device, providing a penetration device, isolating a zone, and penetrating a portion of the formation utilizing the penetration device. Isolating and penetrating may occur in a single trip into the well. The isolation device may include one or more packers. The penetration device may be a pulsating/oscillating hydrajet that introduces fluid pressure waves into the formation.

Abstract: A method for cementing a casing in a wellbore, the method having the following steps: attaching a valve to a casing; locking the valve in an open configuration; running the casing and the valve into the wellbore; reverse circulating a cement composition down an annulus defined between the casing and the wellbore; injecting a plurality of plugs into the annulus; unlocking the valve with the plurality of plugs; and closing the valve.

Abstract: Apparatuses and methods for generating fluid pressure pulses are disclosed. An example apparatus may include a chamber that can collect fluid and an upstream ported disc coupled to a downstream end of the chamber. The upstream ported disc may rotate about a central axis. The upstream ported disc includes an upstream eccentric port that rotates about the central axis as the upstream ported disc rotates. The example apparatus may include a downstream ported disc coupled to a downstream end of the upstream ported disc such that the downstream ported disc remains substantially rotationally fixed relative to the upstream ported disc. The downstream ported disc includes a downstream eccentric port that may align with the upstream eccentric port to form a passageway for fluid to exit from the chamber to outside of the apparatus, at some time in a rotation cycle of the upstream ported disc.

Abstract: The present invention is directed to an apparatus and method for reverse circulation cementing a casing in an open-hole wellbore. The apparatus includes a surface pack-off device, which has a housing defined by an upper section and lower section. A load bearing plate is secured to the housing between the upper and lower sections. The load plate and lower section of the housing cooperate to prevent sloughing of the earth at the surface of the wellbore via a section of casing string. The surface pack-off device also includes a casing hanger, which couples to the casing in the wellbore. Fluid inlets allow the cement to be pumped into the wellbore in the annulus formed between the casing and wellbore sidewall. The method includes the steps of installing the surface pack-off device and operation on reverse circulation of the cement down the annulus.

Abstract: A system for cementing a casing in an open wellbore having no surface casing, wherein an annulus is defined between the casing and the wellbore, the system having: an annular plug around the casing at the mouth of the wellbore; 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: A back pressure valve assembly for use in a well casing string. The valve assembly comprises a housing with a stationary and a floating plate therein. The floating plate is moveable between an open position spaced from the stationary plate and a closed position engaging the stationary plate. Fluid flow downwardly through the valve assembly tends to move the floating plate toward the open position, and fluid flow upwardly through the valve assembly tends to move the floating plate toward the closed position. A finger or key may be used to prevent rotation of the floating plate with respect to the housing.

Abstract: The present invention is directed to a removable surface pack-off device adapted for use in reverse cementing applications. The device includes a housing adapted to be mounted between the ends of an inner casing and an outer casing at or near the surface of a well and at least one fluid passage disposed within the housing, which is adapted to pass fluid, such as cement, from a location outside of the well into an annulus formed between the inner and outer casings. It also includes a first pressure-activated seal disposed between the inner casing and the housing and a second pressure-activated seal disposed between the outer casing and the housing. The device further includes an attachment assembly, which enables the device to be easily removed from the well.