A powered surgical tool includes a motor, a motor control module for controlling the actuation of the motor, and a trigger assembly for allowing the user to enter user-selected commands indicative of desired motor rotation. The trigger assembly includes a number of moving magnets located adjacent the sealed housing that contains the circuitry forming the motor control module. There are a set of magnetic field sensors in the motor control module housing. As the magnets are displaced in response to the user's actuation of the switches, the sensors generate signals representative of the user-selected motor commands. The motor control module further includes a motor control circuit and a direction controller circuit that allow the motor to be driven in either forward, reverse or oscillatory rotation. When the motor is driven the oscillatory rotation, the direction control circuit and the motor control circuit cooperate to ensure the periodic reversal of the motor does not generate significant mechanical vibrations.

Cordless, battery operated surical tool

A directional drilling downhole steering and survey tool for detecting ferromagnetic bodies from an off vertical borehole, transmitting the signals from the downhole sensors to surface equipment while drilling, and for calculation of the range and direction to the detected ferromagnetic body for the use of the directional driller in intercepting or avoiding the ferromagnetic body. In combination with the steering and range and direction to ferromagnetic body capabilities, the downhole tool may also include sensors for detecting formation bed interface, apparatus for electric or gamma ray or radioactive logging, neutron density sensor apparatus and other formation evaluation or correlation apparatus. The downhole tools may be packaged in either an electric line transmitted tool of MWD transmitted tool.

Downhole combination tool

An in situ process for treating an oil containing formation is provided. The process may include providing heat from one or more heaters to at least a portion of the formation. The heat may be allowed to transfer from the one or more heaters to a part of the formation such that heat from the one or more heat sources pyrolyzes at least some hydrocarbons within the part. Hydrocarbons may be produced from the formation.

In situ thermal processing of an oil reservoir formation

In an embodiment, a method of treating a kerogen and liquid hydrocarbon containing formation in situ may include providing heat from one or more heat sources to at least a portion of the formation. Heat may be allowed to transfer from the one or more heat sources to a part of the formation. In some embodiments, at least a portion of liquid hydrocarbons in the part may be mobilized. At least a portion of kerogen in the part may be pyrolyzed. In certain embodiments, a pressure within at least a part of the formation may be controlled. The pressure may be controlled to be at least about 2.0 bars absolute. A mixture may be produced from the formation.

In situ recovery from a kerogen and liquid hydrocarbon containing formation

A process may include providing heat from one or more heaters to at least a portion of a subsurface formation. Heat may transfer from one or more heaters to a part of a formation. In some embodiments, heat from the one or more heat sources may pyrolyze at least some hydrocarbons in a part of a subsurface formation. Hydrocarbons and/or other products may be produced from a subsurface formation. Certain embodiments describe apparatus, methods, and/or processes used in treating a subsurface or hydrocarbon containing formation.

Thermal processes for subsurface formations

A method for determining the distance and direction from a first borehole to a second borehole includes generating, by way of a rotating magnetic field source at a first location in a second borehole, and elliptically polarized magnetic field in the region of the first borehole. First and second sensors positioned at an observation point in the first borehole measure the amplitude and relative phase of respective first and second components of the polarized magnetic field and from these measurements, the direction, relative to the sensors, from the observation point to the first location is determined. The distance between these points is determined by measuring at plural observation points amplitude variations with depth of the rotating magnetic field in the first borehole, and computing theoretical variations in the amplitude for different assumed distances between the observation points and the location of the magnetic field source. The measured amplitude variations are compared with theoretical variations to determine the distance between the first and second boreholes.

Rotating magnet for distance and direction measurements from a first borehole to a second borehole

Logging apparatus for measuring alternating magnetic fields generated by electric current flow on a subterranean target near a borehole is disclosed. Electric current of a predetermined temporal form is made to flow on the target; the resulting magnetic field is measured by magnetometers in a downhole sonde. The orientation of the sonde is fixed by various combinations of gyroscope, accelerometer, magnetometer measurements, and borehole survey data.

Method for determining the location of a deep-well casing by magnetic field sensing

A method and apparatus for precise measurement of the distance and direction from a magnetic field sensor to a nearby magnetic field source includes an elongated iron core solenoid driven by a repetitive, nonsinusoidal current source. In the near field the solenoid has two spaced, temporally varying magnetic poles, and measurement of the distance and direction to this source includes analysis of field components which vary in synchronism with the current source.

Method for near field electromagnetic proximity determination for guidance of a borehole drill

A method and apparatus for determining the distance and direction of a well from a borehole. A toroidal inductor surrounds a drill stem within a borehole. The inductor acts as a primary for a transformer, with the drill stem, the earth surrounding the borehole, and electrically conductive material at the target well forming a single loop transformer secondary. An oscillator is connected to the primary to produce an induced AC current in the secondary. Secondary current flowing in the target well produces an AC secondary magnetic field which is detected at the borehole.

Apparatus for locating an elongated conductive body by electromagnetic measurement while drilling

Methods for determining the distance from a borehole to a nearby, substantially parallel target well for use in guiding the drilling of the borehole, including positioning a magnetic field sensor in the borehole at a known depth and providing a magnetic field source in the target well. The wells may be vertical or horizontal, and the source preferably is a solenoid movable in the target to a location at approximately the same depth as that of the sensor. The distance between the borehole and the solenoid is determined, in one embodiment, by moving the solenoid to depths above and below the depth of the sensor, and detecting maximum field vectors. The distance the solenoid moves between the maxima is the distance between the wells. In another embodiment, the ratio of solenoid magnetic field vectors is used to determine the ratio of the difference in depth z between the solenoid and the sensor to the lateral distance R between the wells. This ratio z/r is then used to determine the separation of the wells.

Arthur F. Kuckes

Papers

Rotating magnet for distance and direction measurements from a first borehole to a second borehole

Method for determining the location of a deep-well casing by magnetic field sensing

Method for near field electromagnetic proximity determination for guidance of a borehole drill

Apparatus for locating an elongated conductive body by electromagnetic measurement while drilling

Method and apparatus for measuring distance and direction by movable magnetic field source