Smith International, Inc.

Other

Camco International (uk) Limited

Schlumberger Technology Corporation

Reedhycalog UK Limited

Reedhycalog, L.p.

Reedhyealog L.p.

Brian P Jarvis

Peter Thomas Cariveau

Lance D Underwood

William E Murray

Brian Williams

Nigel Wilcox

Geoffrey Charles Downton

Gokturk Tunc

Maxim Pushkarev

Lawrence C Lee

Andrei Plop

Daniel D Alvarado

Marcel Boucher

Aaron E Schen

Warren E Askew

Shunetsu Onodera

Craig R Ivie

Shun'etsu Onodera

Malcolm Roy Taylor

Andrew D Murdock

David John Jelley

Simon Johnson

Tim McCarthy

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

Techniques relate to a moving cavity motor or pump, such as a mud motor, including 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, where the apparatus for constraining is operable with the rotor catch. The motor may include a top sub, power section having a progressive cavity motor with a stator and rotor, a rotor catch, and an apparatus between a proximal and distal end of the rotor catch shaft. The apparatus may constrain the radial and/or tangential movement of the rotor catch shaft and the rotor.

Positive displacement motor with radially constrained rotor catch

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, where the apparatus for constraining is operable with the rotor catch.

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.

Disclosed is a method of comparing the relative lateral stability among drill bits (that is, the tendency for a bit to whirl). This allows improved bit selection in applications where whirl is apparent. Because there will likely be many different acceptable bit designs produced by the above method, the comparison of the regenerative forces among these bits allows a customer to make a more informed choice between stability and other performance features among a range of bit designs.

Representation of whirl in fixed cutter drill bits

The present invention is generally directed to a tool for obtaining downhole measurements and methods of using such a tool. In one illustrative embodiment the tool comprises a body, at least one strain gauge cavity in the body, the strain gauge cavity having a strain gauge mounting surface that is located at a position such that a region of approximately zero strain due to at least one downhole operating condition exists on the mounting surface when the tool is subjected to downhole operating conditions, and a strain gauge operatively coupled to the mounting face above the region of approximately zero strain. In another illustrative embodiment, the method comprises providing a measurement tool comprised of a body, at least one strain gauge cavity in the body, the strain gauge cavity having a strain gauge mounting surface that is located at a position such that a region of approximately zero strain due to at least one downhole operating condition exists on the mounting surface when the tool is subjected to downhole operating conditions, and a strain gauge coupled to the mounting face above the region of approximately zero strain. The method further comprises positioning the tool in a subterranean well bore and obtaining measurement data using the strain gauge in the tool.

Apparatus for weight on bit measurements, and methods of using same

The present invention is generally directed to a tool for obtaining weight-on-bit (WOB) measurements and methods of using such a tool. In one illustrative embodiment the tool comprises a body, at least one strain gauge cavity in the body, the strain gauge cavity having a strain gauge mounting surface that is located at a position such that a region of approximately zero axial strain due to downhole pressures during drilling operations exists on the mounting surface when the tool is subjected to downhole pressures during drilling operations, and a weight-on-bit strain gauge operatively coupled to the mounting face above the region of approximately zero axial strain. In another illustrative embodiment, the method comprises providing a weight-on-bit measurement tool comprised of a body, at least one strain gauge cavity in the body, the strain gauge cavity having a strain gauge mounting surface that is located at a position such that a region of approximately zero axial strain due to downhole pressures during drilling operations exists on the mounting surface when the tool is subjected to downhole pressures during drilling operations, and a weight-on-bit strain gauge coupled to the mounting face above the region of approximately zero axial strain. The method further comprises positioning the tool in a drill string comprised of a drill bit, drilling a well bore with the drill string, and obtaining weight-data-on-bit measurement data using the weight-on-bit strain gauge in the tool.

An accelerometer caliper while drilling arrangement comprising a drill bit having an axis of rotation and a gauge region, a caliper tool body, a first accelerometer mounted upon the caliper tool body and arranged to measure acceleration in a first direction, and a second accelerometer mounted upon the caliper tool body and arranged to measure acceleration in a second direction orthogonal to the first direction, wherein the caliper tool body and the drill bit are coupled to one another in such a manner that the first and second accelerometers are mounted in a known relationship to the drill bit.

Accelerometer caliper while drilling

The invention provides a method of detecting, at the surface, the occurrence of torsional vibration in a bottomhole assembly mounted on the drill string of a rotary drilling system. The method includes the steps of: ascertaining natural frequencies of torsional vibration of the bottomhole assembly prior to drilling, and noting at least one reference frequency for an integer wavelength mode of torsional vibration of the bottomhole assembly. During subsequent drilling, the drill string mean square torque at the surface is monitored for a bandwidth around the reference frequency. It is found that peaks in the mean square torque, close to the reference frequency, are indicative of the occurrence of torsional vibration in the bottomhole assembly.

Methods and apparatus for detecting torsional vibration in a bottomhole assembly

A torque transmitting device for use with a rotary drill bit connected to a drill collar, comprises a first member connected to the drill collar, a second member connected to the drill bit, and coupling means connecting the two members together for rotation about a common central axis. The coupling means permits limited relative rotation between the members about the axis, but provides a resistance to rotation of the first member relative to the second member in a forward drilling direction which is greater than its resistance to relative rotation in the reverse direction. The comparatively lower resistance to rotation in the reverse direction prevents momentary reverse rotation of the drill collar, due for example to torsional oscillations, being transmitted to the drill. bit. This reduces the likelihood of damage to the cutters on the drill bit, which might otherwise result from such momentary reverse rotation of the bit.

Growing community of inventors

Bristol, United Kingdom

Brian P Jarvis