US20120193144A1 - Magnetic ranging system for controlling a drilling process - Google Patents

Magnetic ranging system for controlling a drilling process Download PDF

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Publication number
US20120193144A1
US20120193144A1 US13/500,085 US201013500085A US2012193144A1 US 20120193144 A1 US20120193144 A1 US 20120193144A1 US 201013500085 A US201013500085 A US 201013500085A US 2012193144 A1 US2012193144 A1 US 2012193144A1
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US
United States
Prior art keywords
tool
drilling
magnetic field
ranging system
borehole
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US13/500,085
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English (en)
Inventor
Jørgen Hallundbæk
Mathias Francke
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Welltec AS
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Welltec AS
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Filing date
Publication date
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Assigned to WELLTEC A/S reassignment WELLTEC A/S ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: HALLUNDBAEK, JORGEN
Assigned to WELLTEC A/S reassignment WELLTEC A/S ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: Francke, Mathias
Publication of US20120193144A1 publication Critical patent/US20120193144A1/en
Abandoned legal-status Critical Current

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    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B7/00—Special methods or apparatus for drilling
    • E21B7/04—Directional drilling
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B47/00—Survey of boreholes or wells
    • E21B47/02—Determining slope or direction
    • E21B47/022—Determining slope or direction of the borehole, e.g. using geomagnetism
    • E21B47/0228—Determining slope or direction of the borehole, e.g. using geomagnetism using electromagnetic energy or detectors therefor

Definitions

  • the present invention relates to a ranging system for controlling a drilling process downhole.
  • the ranging system has a longitudinal direction and comprises a drilling tool for drilling a first borehole, the drilling tool having a tool axis and comprising a magnetic field source in the form of an electromagnet generating a magnetic field and having a magnetic field source axis.
  • the ranging system comprises a sensing tool arranged in a second borehole for measuring the magnetic field by means of a sensor unit.
  • the purpose is to meet the existing well or borehole at a certain position and, in other cases, the purpose is to drill a new borehole at an exact distance to the existing borehole or well, while ensuring that the distance between the two is substantially the same along a certain stretch.
  • Known tools comprise different solutions to determine this distance.
  • the tools are used to detect magnetic fields for the purpose of determining the distance. Some tools use current in a wire in the existing borehole while others use a magnet rotating in the drilling head.
  • the magnet in the drilling head needs to rotate in order for the sensor to be able to detect the magnetic field and thus the distance of the drilling head in relation to a known position.
  • the drilling heads stops, making it impossible to detect the magnetic field and thus determine the distance and the drilling direction of the drilling head.
  • the drilling process has to be stopped to allow the magnet to be rotated and the tool to be slid back and forth further than the interwell separation, i.e. further than 5-10 meters.
  • the magnetic field sensing device is positioned in the drilling tool. Since the drilling head of the drilling tool is driven by high-pressurised fluid delivered through the drill string, transmission of data from the measurements conducted by the sensing device is very difficult. These tools produce waves in the fluid as a means of communicating data, which is a very slow means of communication and may moreover inhibit the drilling process.
  • a ranging system for controlling a drilling process downhole having a longitudinal direction and comprising:
  • the electromagnet does not have to move in order to make sufficient measurements to be able to calculate the position of the magnet relative to the sensing tool.
  • an imprecise distance between two sets of measurements may occur as a result; however, this is not the case when two sensor units are arranged at a fixed mutual distance.
  • the magnetic field source axis may be substantially parallel to the tool axis.
  • the magnetic field source axis may also be substantially coincident with the tool axis.
  • the sensor units may each comprise a three axis magnetometer for measuring the magnitude and direction of the magnetic field.
  • the magnetometers may be arranged in the same plane in the sensor unit.
  • the second borehole may be an existing borehole.
  • the sensor unit and/or the drilling tool may be driven by a driving unit.
  • the ranging system may further comprise a positioning tool for determining the position of the sensing tool in the second borehole or the position of the drilling tool in the first borehole.
  • This sensing tool may also have means for controlling and/or measuring the position of the sensing tool.
  • the magnetic field source may have a through hole, allowing fluid for driving a drilling head of the drilling tool to pass through the magnetic field source.
  • the ranging system may also comprise a calculation unit for processing magnitude and direction measurements of the magnetic field measured by the sensing tool.
  • the ranging system may comprise a second drilling tool, and the sensing tool may be arranged in or in connection with the second drilling tool so that the first drilling tool comprises the magnetic field source and the second drilling tool comprises the sensing tool.
  • the invention further relates to a method for using the ranging system according to the invention, comprising the steps of:
  • the steps of measuring and calculating are performed simultaneously with drilling the first borehole, meaning that the steps of measuring and calculating are performed at least once an hour, preferably at least once every 0.5 hour, more preferably at least once every 10 minutes.
  • the method may comprise the step of calculating the direction of the drilling head.
  • the method may comprise the step of adjusting the drilling direction based on the calculated relative position of the drilling tool in relation to the sensing tool.
  • the method may comprise the step of adjusting the drilling direction based on the calculated direction and relative position of the drilling tool.
  • the invention relates to any use of the ranging system according to the invention.
  • FIG. 1 shows a cross-sectional view of a ranging system according to the invention arranged in two boreholes downhole
  • FIG. 2 shows a partly cross-sectional view of the drilling tool
  • FIG. 3 shows the magnetic field source in perspective
  • FIG. 4 shows the sensing unit
  • the present invention relates to a ranging system 1 for controlling a drilling process downhole, the ranging system having a longitudinal direction.
  • a ranging system 1 for controlling a drilling process downhole, the ranging system having a longitudinal direction.
  • SAGD steam assisted gravity drainage
  • the ranging system comprises a drilling tool 2 for drilling a new borehole near an existing borehole as shown in FIG. 1 .
  • the drilling tool 2 comprises a drilling head 14 for drilling a first borehole into the formation, and it further comprises a magnetic field source 5 generating a magnetic field 6 , which can be detected by a sensing tool 8 arranged in a second borehole in order to determine the distance between the drilling tool 2 and the sensing tool 8 while drilling and to determine the orientation of the drilling head.
  • the ranging system 1 may also be used while drilling two new boreholes.
  • the magnetic field source 5 is arranged in one drilling tool 2 and a sensor unit 10 of the sensing tool 8 is arranged in, or in connection with, another drilling tool 2 .
  • the drilling direction of the drilling tools 2 can be adjusted to ensure that the distance between the two boreholes remains substantially the same.
  • one of the drilling tools 2 may comprise a positioning tool which is able to determine the position of the drilling tools in relation to the starting point or another known position.
  • the drilling tool 2 has a tool axis 4 and the magnetic field source 5 has a magnetic field source axis 7 which is substantially coincident with the tool axis 4 .
  • the magnetic field source 5 may be any suitable electromagnet. By using an electromagnet, the poles can switch, and the sensor units 10 are thereby able to conduct measurements where the contribution from the earth magnetic field is effectively cancelled out.
  • the sensing tool comprises at least two sensor units 10 arranged at a distance D from each other along an axis of the sensing tool. This means that independent measurements of the magnetic field can be made simultaneously, i.e. there is no need for moving the magnet along the tool axis and thus stop drilling while conducting the measurements.
  • the conducting of measurements is dependent on the magnetic field source rotating and sliding while conducting the measurements. Thus, in prior art tools, measurements can only be performed when the drilling process is stopped.
  • the sensing tool 8 of the present invention is still capable of sensing the magnetic field 6 and thus of continuing to conduct measurements.
  • the sensing tool 8 comprises at least two sensor units 10 .
  • the sensor tool 8 comprises at least two magnetometers, enabling it to calculate the exact position of the drilling head 14 in relation to the sensing tool as well as the direction in which the drilling head 14 is drilling.
  • Each magnetometer measures the local magnitude and direction of the magnetic field 6 and thus provides independent vector measurements without having to move the magnet in relation to the sensors, as is the case in the prior art.
  • sufficient measurements can be conducted to calculate the position of the drilling tool in relation to the sensing tool 8 without having to stop the drilling process.
  • the first vector corresponding to the magnitude and direction of the magnetic field 6 measured in a first sensor unit and the second vector corresponding to the magnitude and direction of the magnetic field 6 measured in a second sensor unit are used to calculate the position of the magnet in the drilling tool.
  • the measurements in the two sensor units 10 are conducted at the same time and, as the distance between the sensor units is known, the position of the magnet can be calculated.
  • the drilling direction of the drilling head 14 can be adjusted so that the direction is the intended direction or so that the distance to a second borehole is the same as the predetermined distance, meaning that the first and second boreholes thus become parallel again.
  • the sensing tool may comprise even more sensing units. Having three or even four sensor units instead of only the two mentioned above will increase the accuracy of the calculated position as well as the direction of the magnetic source and thus the drilling tool. The method described above still applies when using more than two sensor units.
  • the magnet When having an electromagnet as the magnetic field source, the magnet does not have to rotate in order to produce useful measurements as the electromagnet is instead pulsed.
  • the direction of the magnetic field is thus the same relative to the rest of the drill string, simplifying the calculation of the position of the magnet substantially. Even though the electromagnet is rotated, its rotational axis can be coincident with the rotational axis of the drilling tool, thus not affecting the direction of the magnetic field.
  • the sensing tool 8 comprises a driving unit 11 for driving the tool in the longitudinal direction of the second borehole 9 .
  • the sensing tool 8 may comprise means 12 for adjusting the position of the sensing tool, enabling the sensing tool to move back and forth in the borehole to be within the desired range of the drilling tool.
  • the desired range is the range within which the sensing tool 8 has a distance to the magnet of the drilling tool 2 , enabling measurements of good enough quality to accurately and precisely calculate the position of the drilling tool in relation to the sensing tool.
  • the drilling tool 2 may also comprise a driving tool if the drilling process is not performed by means of coiled tubing or drill pipes.
  • the first borehole 3 is the borehole to be drilled
  • the second borehole 9 is an existing borehole, but the second borehole may also be a well or another kind of hole in the formation.
  • the second borehole 9 may be a vertical part of a well which the drilling tool drilling the first borehole deliberately is to collide with or deliberately is to avoid while drilling.
  • the drilling tool 2 typically runs on a high-pressurized fluid.
  • the magnetic field source 5 has a through hole 13 , allowing the fluid to pass through the magnetic field source 5 without losing energy. This is especially convenient when the drilling tool 2 is driven by pressurised fluid through drill pipes or coiled tubing.
  • the ranging system 1 comprises a calculation unit 15 for processing magnitude and direction measurements of the magnetic field 6 measured by the sensor unit 10 .
  • the calculation unit 15 is placed in the sensor unit 10 .
  • the position, r, of the magnet relative to the sensor is calculated as the solution to a minimisation problem.
  • the expression for the field, B, of a magnetic dipole in vector notation is:
  • ⁇ is the permeability
  • d is the dipole vector being substantially coincident with the magnetic field source axis 7
  • r is the position vector
  • r is the distance, i.e. the length of the position vector.
  • ⁇ r ⁇ 3 ⁇ ( B 1 - 3 2 ⁇ ⁇ r ⁇ 2 ⁇ ( r ⁇ B 1 ) ⁇ r ) ⁇ r + s ⁇ 3 ⁇ ( B 2 - 3 2 ⁇ ⁇ r + s ⁇ 2 ⁇ ( ( r + s ) ⁇ B 2 ) ⁇ ( r + s ) )
  • the dipole vector can be calculated directly by insertion into the equation for d.
  • the method using the ranging system comprises the steps of:
  • the steps of measuring and calculating are performed simultaneously with drilling the first borehole, meaning that the steps of measuring and calculating are performed at least once an hour, preferably at least once every 0.5 hours, more preferably at least once every 10 minutes. It is also possible to do this more often, such as several times per second.
  • either the drilling tool 2 or the sensing tool 8 may also have a positioning tool.
  • fluid or well fluid any kind of fluid which may be present in oil or gas wells downhole, such as natural gas, oil, oil mud, crude oil, water, etc.
  • gas is meant any kind of gas composition present in a well, completion, or open hole
  • oil is meant any kind of oil composition, such as crude oil, an oil-containing fluid, etc.
  • Gas, oil, and water fluids may thus all comprise other elements or substances than gas, oil, and/or water, respectively.
  • a casing any kind of pipe, tubing, tubular, liner, string, etc. used downhole in relation to oil or natural gas production.
  • a downhole tractor can be used to push the tools all the way into position in the well.
  • a downhole tractor is any kind of driving tool capable of pushing or pulling tools in a well downhole, such as a Well Tractor®.

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  • Geology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mining & Mineral Resources (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Electromagnetism (AREA)
  • Geophysics (AREA)
  • Geophysics And Detection Of Objects (AREA)
  • Excavating Of Shafts Or Tunnels (AREA)
  • Drilling And Boring (AREA)
  • Processing Of Stones Or Stones Resemblance Materials (AREA)
US13/500,085 2009-10-30 2010-10-29 Magnetic ranging system for controlling a drilling process Abandoned US20120193144A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
EP09174667A EP2317069A1 (fr) 2009-10-30 2009-10-30 Système de télémetrie par magnétisme pour contrôler un procès de forage
EP09174667.7 2009-10-30
PCT/EP2010/066443 WO2011051431A1 (fr) 2009-10-30 2010-10-29 Système de télémétrie magnétique pour contrôler un processus de forage

Publications (1)

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US20120193144A1 true US20120193144A1 (en) 2012-08-02

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US13/500,085 Abandoned US20120193144A1 (en) 2009-10-30 2010-10-29 Magnetic ranging system for controlling a drilling process

Country Status (8)

Country Link
US (1) US20120193144A1 (fr)
EP (2) EP2317069A1 (fr)
CN (1) CN102782250A (fr)
AU (1) AU2010311357A1 (fr)
BR (1) BR112012009224A2 (fr)
CA (1) CA2774292A1 (fr)
MX (1) MX2012004930A (fr)
WO (1) WO2011051431A1 (fr)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014089402A2 (fr) * 2012-12-07 2014-06-12 Halliburton Energy Services Inc. Système de télémétrie à excitation superficielle pour application de drainage par gravité au moyen de vapeur (sagd)
US20150240623A1 (en) * 2012-09-18 2015-08-27 Shell Oil Company Method of orienting a second borehole relative to a first borehole
US20170211374A1 (en) * 2014-09-11 2017-07-27 Halliburton Energy Services, Inc. Rare earth alloys as borehole markers
US20180038984A1 (en) * 2014-09-10 2018-02-08 Beijing Nano Tesla Technology Co. Ltd Rotating Magnetic Field Range Finder and its Measurement Method for Relative Separation Between Drilling Wells
US10408044B2 (en) 2014-12-31 2019-09-10 Halliburton Energy Services, Inc. Methods and systems employing fiber optic sensors for ranging
EP3725998A1 (fr) * 2019-04-18 2020-10-21 Sandvik Mining and Construction Oy Appareil et procédé pour déterminer la position d'un outil de forage pendant le forage
US11781421B2 (en) 2020-09-22 2023-10-10 Gunnar LLLP Method and apparatus for magnetic ranging while drilling

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CN103573248B (zh) * 2012-07-25 2017-02-08 中国石油化工股份有限公司 钻井的磁干扰测量装置
CN104919136B (zh) * 2012-12-21 2018-07-10 哈利伯顿能源服务公司 使用第三井参照来执行距离测量的系统和方法
CN107989601B (zh) * 2017-12-22 2020-12-15 西安石油大学 一种用于同时钻多口垂直井的磁测距方法
CN108166972A (zh) * 2017-12-22 2018-06-15 西安石油大学 一种控制平行井钻进的磁测距系统及方法
CN115949388B (zh) * 2023-02-20 2024-05-07 四川轻化工大学 一种套管防碰测距预警方法及测量单元

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US20090308657A1 (en) * 2008-06-13 2009-12-17 Schlumberger Technology Corporation Magnetic ranging and controlled earth borehole drilling
US20110133741A1 (en) * 2008-06-25 2011-06-09 Brian Clark System and method for employing alternating regions of magnetic and non-magnetic casing in magnetic ranging applications

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Publication number Priority date Publication date Assignee Title
US20070278008A1 (en) * 2006-06-05 2007-12-06 Vector Magnetics Llc Electromagnetically determining the relative location of a drill bit using a solenoid source installed on a steel casing
US20090308657A1 (en) * 2008-06-13 2009-12-17 Schlumberger Technology Corporation Magnetic ranging and controlled earth borehole drilling
US20110133741A1 (en) * 2008-06-25 2011-06-09 Brian Clark System and method for employing alternating regions of magnetic and non-magnetic casing in magnetic ranging applications

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150240623A1 (en) * 2012-09-18 2015-08-27 Shell Oil Company Method of orienting a second borehole relative to a first borehole
US9932819B2 (en) * 2012-09-18 2018-04-03 Shell Oil Company Method of orienting a second borehole relative to a first borehole
WO2014089402A3 (fr) * 2012-12-07 2014-08-28 Halliburton Energy Services Inc. Système de télémétrie à excitation superficielle pour application de drainage par gravité au moyen de vapeur (sagd)
WO2014089402A2 (fr) * 2012-12-07 2014-06-12 Halliburton Energy Services Inc. Système de télémétrie à excitation superficielle pour application de drainage par gravité au moyen de vapeur (sagd)
US10145231B2 (en) 2012-12-07 2018-12-04 Halliburton Energy Services, Inc. Surface excitation ranging system for SAGD application
US10760407B2 (en) 2012-12-07 2020-09-01 Halliburton Energy Services, Inc. Surface excitation ranging system for SAGD application
US10520632B2 (en) * 2014-09-10 2019-12-31 Beijing Nana Tesla Technology Co. Ltd Rotating magnetic field range finder and its measurement method for relative separation between drilling wells
US20180038984A1 (en) * 2014-09-10 2018-02-08 Beijing Nano Tesla Technology Co. Ltd Rotating Magnetic Field Range Finder and its Measurement Method for Relative Separation Between Drilling Wells
US20170211374A1 (en) * 2014-09-11 2017-07-27 Halliburton Energy Services, Inc. Rare earth alloys as borehole markers
US10539006B2 (en) * 2014-09-11 2020-01-21 Halliburton Energy Services, Inc. Rare earth alloys as borehole markers
US10408044B2 (en) 2014-12-31 2019-09-10 Halliburton Energy Services, Inc. Methods and systems employing fiber optic sensors for ranging
EP3725998A1 (fr) * 2019-04-18 2020-10-21 Sandvik Mining and Construction Oy Appareil et procédé pour déterminer la position d'un outil de forage pendant le forage
US11781421B2 (en) 2020-09-22 2023-10-10 Gunnar LLLP Method and apparatus for magnetic ranging while drilling

Also Published As

Publication number Publication date
AU2010311357A1 (en) 2012-04-12
CN102782250A (zh) 2012-11-14
MX2012004930A (es) 2012-05-22
BR112012009224A2 (pt) 2016-08-23
EP2317069A1 (fr) 2011-05-04
EP2494148A1 (fr) 2012-09-05
CA2774292A1 (fr) 2011-05-05
WO2011051431A1 (fr) 2011-05-05

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Effective date: 20120322

Owner name: WELLTEC A/S, DENMARK

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