The present invention provides systems utilizing fiber optics for monitoring downhole parameters and the operation and conditions of downhole tools. In one system fiber optics sensors are placed in the wellbore to make distributed measurements for determining the fluid parameters including temperature, pressure, fluid flow, fluid constituents and chemical properties. Optical spectrometric sensors are employed for monitoring chemical properties in the wellbore and at the surface for chemical injection systems. Fiber optic sensors are utilized to determine formation properties including resistivity and acoustic properties compensated for temperature effects. Fiber optic sensors are used to monitor the operation and condition of downhole devices including electrical submersible pumps and flow control devices. In one embodiment, a common fluid line is used to monitor downhole parameters and to operate hydraulically-operated devices. Fiber optic sensors are also deployed to monitor the physical condition of power lines supplying high electric power to downhole equipment. A light cell disposed downhole is used to generate electric power in the wellbore, which is used to charge batteries.

Monitoring of downhole parameters and tools utilizing fiber optics

An electric power tool includes: a brushless motor having a plurality of stator windings and configured to rotate in accordance with voltages applied to the plurality of stator windings, an induced voltage being generated in accordance with a rotation of the brushless motor; a rectifier circuit configured to rectify an AC voltage; a smoothing capacitor configured to smooth the AC voltage rectified by the rectifier circuit to a pulsation voltage having a maximum value larger than the induced voltage and a minimum value smaller than the induced voltage; and an inverter circuit configured to perform switching operations to output the pulsation voltage to the plurality of stator windings by rotation.

Electric power tool

A steerable rotary drilling system has a bottom hole assembly which includes, in addition to the drill bit, a modulated bias unit and a control unit, the bias unit comprising a number of hydraulic actuators around the periphery of the unit, each having a movable thrust member which is hydraulically displaceable outwardly for engagement with the formation of the borehole being drilled. Each actuator may be connected, through a control valve, to a source of drilling fluid under pressure and the operation of the valve is controlled by the control unit so as to modulate the fluid pressure supplied to the actuators as the bias unit rotates. If the control valve is operated in synchronism with rotation of the bias unit the thrust members impart a lateral bias to the bias unit, and hence to the drill bit, to control the direction of drilling. Pulses transmitted through the drilling fluid as a result of operation of the bias unit are detected and interpreted at the surface, or at a different location downhole, to obtain information regarding the operation of the bias unit or other parts of the bottom hole assembly. Data signals from downhole sensors may be arranged to modify the control and operation of the bias unit in such manner that the data is encoded as pulses generated in the drilling fluid by the bias unit.

Steerable rotary drilling system

The invention provides an apparatus and method for perforating and treating multiple intervals of one or more subterranean formations (86) intersected by a wellbore by deploying a bottom-hole assembly having a perforating device (134) and at least one sealing mechanism (120) within said wellbore. The perforating device (134) is used to perforate the first interval to be treated. Then the bottom-hole assembly is positioned within the wellbore such that the sealing mechanism (120), when actuated, establishes a hydraulic seal in the wellbore to positively force fluid to enter the perforations (230, 231) corresponding to the first interval to be treated. A treating fluid is then pumped down the wellbore and into the perforations (230, 231) created in the perforated interval. The sealing mechanism (120) is released, and the steps are then repeated for as many intervals as desired, without removing the bottom hole assembly from said wellbore.

Method and apparatus for stimulation of multiple formation intervals

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 and system for lateral drilling with respect to a main well which is cased by a casing string. At least a part of the casing string provides a lateral opening adapted to enable drilling of a lateral well. A guiding device is positioned at a part of the casing string in front of the lateral opening and the guiding device is controlled from the surface of the main well. A lateral casing string equips the lateral well and provided a sub for connecting the lateral casing string to the main string in the main well.

Device, system and method for drilling and completing a lateral well

A process for installing seismic sensors inside a petroleum production well equipped with a cemented casing involves arranging the seismic sensors along an outer surface of the casing before being descended into a drilled well and cementing a ring-shaped space between the casing and the well so as to acoustically connect the sensors to geological formations. The sensors and transmission cables which link them to the surface are secured to centering devices guiding the descent of the casing or to the casing outer wall, possibly by means of a coating of damping material. The sensors may be inserted into sleeves secured outside the casing.

Process and device for installing seismic sensors inside a petroleum production well

A well tool such as a measuring sonde is arranged in a protective housing and introduced into a well at the end of a tubing. A retractable latching device fastens the tool to the housing and to an electrical transmission cable. The tubing is connected with a pumping assembly capable of circulating up to the housing a cooling fluid at a temperature lower than the temperature prevailing in the well and the tool is operated by moving the tool out of the housing and by bringing the tool regularly back into the housing, which is permanently cooled by the fluid.

Method and device for carrying out interventions in wells where high temperatures prevail

A method for effecting logging or servicing operations in a predetermined zone of a well, following an initial portion thereof, comprising fastening a logging or servicing tool body at the end of a string of rods lowered into the well, said tool body being provided with an electric male connector, lowering at the end of an electric transmission cable, from the surface, a female connector adapted to fit the male connector, coupling said female and male connectors by the action of a force generated at least partly by the pressure of a fluid pumped through the string of rods, supplying electric power, through said transmission cable and said connectors, to said logging or servicing tool for its operation in said predetermined zone, and with rotating means located between the string of rods and said tool, rotating the tool without rotating the whole string of rods.

Method and device for effecting, by means of specialized tools, such operations as measurements in highly inclined to the vertical or horizontal well portions

A system for carrying out measurements and/or services in a wellbore or a well in the process of being drilled includes an electrical link connecting a surface control unit to a sonde comprising measuring and/or servicing devices fastened to a lower end of a cable section; an assembly including a sub for anchoring the sonde; a cable section having at an upper end thereof a first intermediate electrical connector integral with a support; the electrical link being provided by a cable linked to the surface control unit and having at a lower end thereof a second intermediate electrical connector adapted to be connected to the first intermediate electrical connector. The support is adapted to be made integral with an inner wall or a drill string.

Christian Wittrisch

Papers

Device, system and method for drilling and completing a lateral well

Process and device for installing seismic sensors inside a petroleum production well

Method and device for carrying out interventions in wells where high temperatures prevail

Method and device for effecting, by means of specialized tools, such operations as measurements in highly inclined to the vertical or horizontal well portions

System, support for carrying out measurings and/or servicings in a wellbore or in a well in the process of being drilled and uses thereof