Abstract: In one embodiment, an optical fiber includes a first layer having a first refractive index and a second layer surrounding the first layer, where the second layer has a second refractive index, an inner radius, and an outer radius. The optical fiber also includes a third layer surrounding the second layer, where the third layer has a third refractive index, where the first refractive index is less than the second refractive index, where the third refractive index is less than the second refractive index, and where a ratio of the outer radius to the inner radius is less than 1.5.

Abstract: In one embodiment, an optical fiber includes a first layer having a first refractive index and a second layer surrounding the first layer, where the second layer has a second refractive index, an inner radius, and an outer radius. The optical fiber also includes a third layer surrounding the second layer, where the third layer has a third refractive index, where the first refractive index is less than the second refractive index, where the third refractive index is less than the second refractive index, and where a ratio of the outer radius to the inner radius is less than 1.5.

Abstract: A method and apparatus for selectively reciprocating a downhole device in a wellbore relative to an upper portion of production tubing, so that the upper portion of production tubing does not need to be lifted to operate the downhole device. A shift tool between the upper production tubing and the deflector assembly is designed to lift a deflector assembly independently of the upper production tubing. The shift tool is operated by pressurized fluid delivered from the surface, for example with a fluid-delivery device on the end of coiled tubing lowered through the production tubing.

Abstract: A jetting hose is conveyed downhole retracted on the end of a tubing string (coiled tubing) for jetting lateral boreholes from a main wellbore. The apparatus allows the operator to sense the speed at which the jetting hose and nozzle are penetrating the formation and adjust the coiled tubing feed-in rate accordingly, optimizing both the direction and length of the lateral borehole relative to the main wellbore.

Abstract: An apparatus and method for improving control over the milling force applied to a milling bit that is turned through a rotary drive to form a hole in a wellbore casing. A bit-weighting sub is applied between the tubing used to lower the rotary drive's motor into the wellbore and the rotary drive itself, the sub serving to take the weight of the tubing off the rotary drive when the motor lands in operative connection with the drive, and further serving to apply a known milling force to the drive (and thus to the bit) independent of the weight of the tubing. In a preferred form the sub includes a spring that is compressed against the drive when the tubing and motor are landed.

Abstract: A jetting hose is conveyed downhole retracted within a tubing string for jetting lateral boreholes from a main wellbore, is released at the jetting depth and pumped from the tubing string and into a lateral borehole with jetting fluid. A piston is secured to the upper end of the jetting hose, and the pumped jetting fluid drives the piston. A speed control regulates the penetration rate of the jetting hose into the formation independent of the tubing string weight.

Abstract: A jetting hose is conveyed downhole retracted on the end of a tubing string (coiled tubing) for jetting lateral boreholes from a main wellbore. The apparatus allows the operator to sense the speed at which the jetting hose and nozzle are penetrating the formation and adjust the coiled tubing feed-in rate accordingly, optimizing both the direction and length of the lateral borehole relative to the main wellbore.

Abstract: An apparatus and method for improving control over the milling force applied to a milling bit that is turned through a rotary drive to form a hole in a wellbore casing. A bit-weighting sub is applied between the tubing used to lower the rotary drive's motor into the wellbore and the rotary drive itself, the sub serving to take the weight of the tubing off the rotary drive when the motor lands in operative connection with the drive, and further serving to apply a known milling force to the drive (and thus to the bit) independent of the weight of the tubing. In a preferred form the sub includes a spring that is compressed against the drive when the tubing and motor are landed.

Abstract: The present application is directed to an apparatus for forming one or more holes in a wellbore casing, the apparatus comprising a deflector assembly and a drive assembly to drive said deflector assembly, wherein the deflector assembly may be optionally assembled at a surface of the wellbore prior to casing hole formation, and to methods employing the apparatus.

Abstract: The present application is directed an apparatus for installing boreholes in the formation surrounding a main wellbore, the apparatus comprising an indexing tool comprising an indexing deflector and a deflector shoe; the deflector shoe comprising an opening therethrough configured to receive a borehole forming member; wherein the indexing deflector is configured to direct the deflector shoe from a first setting to at least a second setting for the installation of boreholes at each setting through said opening; to methods employing the apparatus, and methods for using the indexing tool to locate and access boreholes.

Abstract: A jetting hose is conveyed downhole retracted within a tubing string for jetting lateral boreholes from a main wellbore, is released at the jetting depth and pumped from the tubing string and into a lateral borehole with jetting fluid. A piston is secured to the upper end of the jetting hose, and the pumped jetting fluid drives the piston. A speed control regulates the penetration rate of the jetting hose into the formation independent of the tubing string weight.

Abstract: The present application is directed to an apparatus for forming one or more holes in a wellbore casing, the apparatus comprising a deflector assembly and a drive assembly to drive said deflector assembly, wherein the deflector assembly may be optionally assembled at a surface of the wellbore prior to casing hole formation, and to methods employing the apparatus.

Abstract: The present application is directed an apparatus for installing boreholes in the formation surrounding a main wellbore, the apparatus comprising an indexing tool comprising an indexing deflector and a deflector shoe; the deflector shoe comprising an opening therethrough configured to receive a borehole forming member; wherein the indexing deflector is configured to direct the deflector shoe from a first setting to at least a second setting for the installation of boreholes at each setting through said opening; to methods employing the apparatus, and methods for using the indexing tool to locate and access boreholes.