Schlumberger Technology Corporation

Anadrill, Inc.

Smith International, Inc.

Warren E Askew

Alan M Eddison

Peter Thomas Cariveau

Geoffrey Charles Downton

Lance D Underwood

Gokturk Tunc

Maxim Pushkarev

Lawrence C Lee

Brian P Jarvis

William E Murray

Shunetsu Onodera

Andrei Plop

Brian Williams

Nigel Wilcox

Daniel D Alvarado

Jean-Michel Hache

Mark Milkovisch

Steven E Buchanan

Richard Dan Ward

Bo Yang

Adam Cygan

Gokhan Erol

Bernhard Prevedel

Techniques involve a motor assembly including a rotor and a stator. The stator includes a contact surface for contacting an outer surface of the rotor. The contact surface includes a rigid material. The motor assembly also includes at least one constraint disposed along a length of the motor assembly, where the constraint constrains a radial and/or tangential movement of the rotor relative to the stator. The at least one constraint may be disposed at one or more proximate ends of the motor assembly, and/or along the length of the motor assembly. The contact surface of the stator may have a profile including peaks and valleys, and in some embodiments, the contact surface may be treated to reduce friction and/or wear.

Apparatus and method for controlling or limiting rotor orbit in moving cavity motors and pumps

A moving cavity motor or pump, such as a mud motor, comprising: a rotor, a stator, and one or more apparatus for constraining (i.e., controlling or limiting) the movement of the rotor relative to the stator.

A downhole coring tool conveyable within a borehole extending into a subterranean formation, wherein the downhole coring tool comprises a housing, a hollow coring bit extendable from the housing, a first motor operable to rotate the coring bit, and a second motor operable to extend the coring bit into the subterranean formation through a sidewall of the borehole in a direction not substantially parallel to a longitudinal axis of the borehole proximate the downhole coring tool. A static sleeve disposed in but rotationally independent of the coring bit receives a portion of a core sample of the formation resulting from extension of the coring bit into the formation. The static sleeve comprises a protrusion extending radially inward toward the core sample sufficiently to mark the core sample.

Downhole coring tools and methods of coring

The present invention provides a hydraulically actuated downhole adjustable bent housing for use in directional drilling of bore holes and wells that allows adjustment of the housing from aligned to a bent configuration without raising or lowering the drillstring. The present invention also provides a method of directionally drilling a bore hole or a well using an downhole adjustable bent housing that can be operated without raising or lowering the drillstring.

Downhole adjustable bent housing for directional drilling

An articulated directional drilling tool assembly for use in drilling a borehole having a short radius of curvature includes a mud motor having an upper housing that is pivotally connected to a lower housing having upper and lower sections. Such sections are joined together in a manner to define a bend angle. The drill bit box carries a stabilizer that centers it in the borehole. The upper housing section carries an eccentric stabilizer assembly which tilts it toward the low side of the borehole to increase the effectiveness of the bend angle. A hydraulic piston also can be used to increase the side loading on the bit and cause it to drill a sharply curving borehole. The upper housing of the motor is connected to the lower housing by an articulative, torque transmitting coupling, and the upper motor housing is connected to an orientation measuring sub thereabove in the same manner.

Articulated directional drilling motor assembly

In accordance with illustrative embodiments of this invention, a downhole adjustable stabilizer includes a sleeve having outwardly extending blades and mounted for limited rotation on a mandrel, vertically aligned sets of radially movable buttons mounted in bores in the blades, and longitudinal flats on the outer periphery of the mandrel that when radially aligned with the respective sets of buttons allows them to shift inward to positions where the stabilizer becomes undergage and can be tilted in the borehole. Some spring loaded buttons drag against the borehole wall to provide frictional restraint against rotation of the housing. The blades can each have an inclined side surface that causes the sleeve to be rotated to its position relative to the mandrel where the sets of buttons are retracted as the stabilizer slides downward in the borehole. In another embodiment a hydraulic delay is provided which restrains relative rotation in the direction which cause the buttons to extend to their full gauge diameter.

Downhole adjustable stabilizer

Methods are provided for controlling the direction of a borehole drilled by a downhole motor, including the steps of positioning downhole adjustable bent housing and near-bit stabilizer in the drill string, adjusting the bent housing from its normally straight condition to its bent condition to effect borehole curvature, and using the stabilizer in its undergage condition to enhance the inclination. The Measurements are made from which the inclination with respect to the vertical and the azimuth can be determined and telemetered uphole for processing, display, and recording. Preferably the directional measurements are made at two locations, one below the bent point and one above it. These two sets of measurements can be compared to confirm the bend angle and to obtain a definition of the orientation of the plane of the bend angle so that the drilling path can be accurately controlled. Use of the present invention eliminates having to superimpose rotation of the deflected drill string in order to drill straight ahead because the bend angle can be eliminated by downhole adjustment.

Directional drilling methods and apparatus

In accordance with an illustrative embodiment of the present invention, a downhole adjustable apparatus for creating a bend angle in a drill string includes a mandrel mounted for rotation between first and second angular positions within a housing, the mandrel being telescoped into the housing on an axis that is inclined with respect to the principle axial centerline of the housing, so that in one rotational position of the mandrel the housing is axially aligned with the centerline of a drilling motor and in another rotational position that is 180.degree. from the initial position the housing is slightly inclined with respect to the centerline of such drilling motor to establish a bend angle. Further manipulation of the mandrel is used to return the members to their original positions for straight-ahead drilling.

Downhole adjustable bent assemblies

In accordance with an illustrative embodiment of the present invention, a hydraulic drilling jar includes a mandrel and a housing movable between extended and retracted relative positions to deliver jarring blows to a struck object, a piston on the mandrel that slides in a cylinder in the housing, and a restriction assembly on the housing having an internal seal that engages an enlarged section of the mandrel to enclose a high pressure, oil-filled chamber between the piston and the restriction assembly, the restriction assembly including a pin check valve that provides a very slow leakage of oil from the high pressure chamber while the enlarged section of the mandrel is engaged with the seal. An oil-filled compensating chamber on the opposite side of the restriction means from the high pressure chamber has its pressure equalized with the pressure inside the mandrel by ports through the wall of the mandrel.

Growing community of inventors

Houston, TX, United States of America

Warren E Askew