Schlumberger Technology Corporation

Keith Nelson

Franz Aguirre

Todor K Sheiretov

Alexander H Slocum

Douglas W Grant

Gohar Saeed

Irene Gabler

James Bayless

Brandon Martin

A technique facilitates conveyance of equipment along a wellbore or other tubular structure. A tractor is provided with a plurality of wheels oriented to engage a surrounding wall. Rotation of the wheels drives the tractor and causes longitudinal movement of the tractor with respect to the surrounding wall via a tangential force created between each wheel and the surrounding wall. Each wheel comprises teeth having a wheel tooth geometry which enhances cooperation with the surrounding wall. For example, the wheel tooth geometry may be designed to cooperate with the tangential force to push debris out of the teeth of each wheel during rotation of the wheel along the surrounding wall. In some applications, the wheel tooth geometry is designed to present a plurality of raised, rounded surfaces which engage the surrounding wall with a low stress impact.

System and method for conveying

A transmission for rotatably coupling an input shaft with an output shaft about a longitudinal axis is disclosed, which may include a continuous variable transmission and an output torque sensing control mechanism. The continuous variable transmission may be a toroidal disc continuous variable transmission. The output torque sensing control mechanism may include a spring and an intermediary output shaft rotatably connected with an output rotating member of the continuous variable transmission, and the output shaft may be externally threaded and matable with an internally threaded portion of the intermediary output shaft.

Controllable mechanical transmission for downhole applications

A downhole tractor assembly that is configured for open-hole applications. The assembly includes a force monitoring mechanism to help monitor and control forces imparted through a drive mechanism of the tractor in real time. As such, damage to open-hole formations due to excessive tractoring forces may be minimized along with mechanical damage to the tractor. Furthermore, the drive mechanism of the tractor may include multiple sondes and bowsprings with gripping saddles specially configured for contacting the well wall across a large area in a non-point and line manner so as to avoid digging into and damaging the well wall during tractoring.

Force monitoring tractor

A mechanism to enhance disengagement of release assembly portions from one another when disposed in a well. The mechanism may be disposed at an internal rod of the release assembly and configured to prevent frictional resistance to shifting of the rod.

Friction reduction mechanism for a downhole release assembly

A downhole tractor assembly that is configured for open-hole applications and of a self-aligning nature. The self-aligning nature of the assembly is effectuated through a tractor portion which is rotable about an axis of an elongated body of the assembly independent of a separate centralizing portion of the assembly. That is, the tractor portion, configured for interfacing an open-hole well wall of potentially irregular morphology, is independently rotable so as to maintain a position of substantially optimized driving friction at the interface during tractoring. Maintenance of optimized driving friction in this manner may occur irrespective of the orientation of the centralizing portion of the assembly.

Self-aligning open-hole tractor

A passive centralizer for stably centering within a well. The centralizer may be of a retracted profile for advancement within the well and deployable for centralization upon reaching an operation site. Deployment may be achieved in an automated manner without the requirement of operator interaction therefor. Furthermore, the centralizer may be truly passive in that energy for deployment may be stored entirely within the passive centralizer prior to its insertion within the well. The passive centralizer may also be compressed following centralization by any number of downhole restrictions. In this manner the passive centralizer may also be readily withdrawn from the well.

Growing community of inventors

Sugar Land, TX, United States of America

Keith Nelson