CN102996120B - A kind of relief well based on three electrode systems is communicated with detection system with accident well - Google Patents

Abstract

The present invention relates to a kind of relief well based on three electrode systems and be communicated with detection system with accident well.This system comprises surface power supply equipment, ground signal collecting device, ground relief well and is communicated with accident well and detects computing system, Surface electrode, down-hole three electrode system, underground probe; Surface power supply equipment is that down-hole three electrode system, ground signal collecting device and ground relief well are communicated with to detect with accident well and calculate system power supply; Ground signal collecting device is communicated with to detect in computing system with accident well calculates being sent to ground relief well after the data conversion format received, and shows in the mode of numeral, word and/or figure.The present invention adopts down-hole three electrode system as current signal emission source, ensure that the electric current flowed out from main electrode can not flow along relief well borehole axis direction, can direct detection relief well shaft bottom to the distance and bearing of accident well, avoid accumulated error, be applicable to cannot be close near accident well well head operating mode, normally can work in deep-well.

Description

A kind of relief well based on three electrode systems is communicated with detection system with accident well

Technical field

The invention belongs to subterranean resource drilling field of engineering technology, particularly, relate to a kind of relief well based on three electrode systems and be communicated with detection system with accident well.

Background technology

In recent years, the frequent of offshore drilling platform oil spill disaster causes serious ecological disaster and extremely bad social influence.Relief well be at sea with land drilling well in occur Oil/gas Well catch fire or gas blowout accident time the accident settlement method that often adopts, its general principle is that a bite directional well is made in the safety zone near accident well, the track of its well track and accident well is converged in certain layer of position on stratum, by highdensity drilling fluid or cement by relief well input accident well, to reach the object of the fire extinguishing of oil (gas) well or uniform blowout.On April 20th, 2010, there is blowout and cause the deep sea drilling crude oil leakage reaching the several months in Gulf of Mexico well MC252#1, not only makes BP company be subject to great economic loss, and cause serious ecological disaster and social influence.After in this accident, BP company have employed the emergency measure of multiple process draining accident, finally utilize the pressure test operation of relief well to obtain the final victory of process draining accident, relief well technology is subject to extensive concern at home and abroad again.At present, relief well is still the most reliable method thoroughly solving Leakage.

In the process of boring deep-well Oil/gas Well, because accident well and relief well can not be only straight well, well type will be more complicated, and the accurate control of well track is also more difficult.Due to the uncertainty of well track, the accurately detecting of relief well and accident well offset well distance and bearing is one of successful key link of relief well technology.And general more dangerous near accident well well head, in order to ensure the safety of personnel and drilling equipment, the pithead position of relief well is general even farther apart from accident well pithead position hundreds of rice.In order to make relief well crossing with accident well, the general more complicated of well track of relief well, which exasperates in the uncertainty needing to be communicated with position accident well and relief well relative position.The Wellspot instrument of external development meets the engineering demand of relief well and accident well accurate commutation substantially at present.Owing to generally catching fire near accident well well head or discharging toxic gas, be conventionally used to the rotating excitation field guiding distance measurement system (RotatingMagnetRangingSystem of offset well distance electromagnetic positioning, be called for short RMRS) and electromagnetic guide instrument (MagneticGuidanceTool, be called for short MGT) etc. prospecting tools cannot insert in accident well, and all measureing equipments of Wellspot steering tool are all placed in relief well, can distance in relief well between direct detection relief well and accident well and its orientation relative to accident borehole axis line, therefore this instrument can guide relief well crossing with the well depth place that accident well is designing, be widely applied in being communicated with of its relief well abroad and accident well.

Wellspot instrument is a kind of efficient tool controlling relief well and be communicated with accident well, and it can guide relief well to realize docking with the success of accident well with various well type according to actual formation situation.When accident well is oil/gas deep well, well track has great uncertainty, and relief well needs to be communicated with accident well less parallel, and relief well well type now can be designed to five-part form.But in actual applications, the well depth of some accident well is more shallow, therefore relief well is comparatively near to the connectivity points distance well head of accident well, causes the object that cannot be reached kill-job by the relief well of routine.In this case, relief well will need to be communicated with wide-angle with accident well, and even close to intersecting vertically, relief well well type now can be designed to five-part form.

At present, the core technology of external designed Wellspot steering tool is still maintained secrecy and is monopolized, and China still lacks further investigation in this respect.Therefore, present inventor special research and design " a kind of relief well based on three electrode systems is communicated with detection system with accident well ", the present invention adopts three electrode systems as current signal emission source, the intensity of current signal emission source can be improved, the Low-frequency alternating currents that greatly increase accident casing is assembled, thus make the inserting tube in relief well relatively larger low frequency alternating magnetic field can be detected, be easy to increase finding range.

Summary of the invention

For overcoming above-mentioned defect, the invention provides a kind of relief well based on three electrode systems and be communicated with detection system with accident well, native system accurately can measure spacing and the orientation of relief well and accident well within the specific limits, for the accurate commutation of relief well and accident well provides one effectively to detect and control device.

For achieving the above object, the present invention adopts following scheme:

Relief well based on three electrode systems is communicated with detection system with accident well, comprising: surface power supply equipment, ground signal collecting device, ground relief well are communicated with accident well and detect computing system, Surface electrode, down-hole three electrode system, underground probe; Surface power supply equipment is positioned near relief well well head, and for providing Low-frequency alternating currents for down-hole three electrode system, to be also simultaneously ground signal collecting device with ground relief well be communicated with to detect with accident well calculates system power supply; Surface electrode is connected with the wellhead casing pipe of relief well and contact is good, the output of surface power supply equipment be connected with down-hole three electrode system, input is connected with Surface electrode; Underground probe is for the low frequency alternating magnetic field detecting the gravitational field at underground probe place, earth's magnetic field and produced by the Low-frequency alternating currents that accident casing is assembled, ground signal collecting device is connected with underground probe by logging cable, and receives the data that underground probe detects, reached ground by logging cable; Ground signal collecting device is communicated with to detect in computing system with accident well calculates being sent to ground relief well after the data conversion format received, obtain the relative spatial location data of underground probe in relief well and accident casing, show in the mode of numeral, word and/or figure.

Preferably, surface power supply equipment comprises 380V AC power, step-up transformer, AC/DC converter and frequency controller; First the output of 380V AC power passes through step-up transformer, the voltage that 380V AC power provides is risen to 1000V by step-up transformer, after AC/DC converter, convert the high direct voltage of 1000V to, three electrode systems 7 are exported and can reach the electric current that amplitude is 20A, utilize Single-chip Controlling frequency controller to make it high pressure of 1000V be converted to the alternation square-wave voltage of 0.25Hz frequency, then this alternation square-wave voltage is sent to electrode system place, down-hole three and does again and export further; The input of 380V AC power is connected with Surface electrode.

Preferably, down-hole three electrode system comprises electrode system cable interface, electrode system metal shell, two bucking electrodes, two insulating trips and main electrodes; Down-hole three electrode system is connected with seven core cable by electrode system cable interface; Two bucking electrodes and main electrode are cylinder, and main electrode is positioned at centre, and length is 0.15m, and two bucking electrodes are arranged in the upper and lower both sides of main electrode symmetrically, and the length of bucking electrode is 0.7m, and two bucking electrodes are connected by short-circuit line in inside; Separate with insulating trip between bucking electrode and main electrode, the thickness of insulating trip is 0.025m; Two bucking electrodes, two insulating trips are identical with the diameter of main electrode.

Preferably, the output of two-way identical polar is divided into after the alternation square-wave voltage that the amplitude that surface power supply equipment provides is 1000V, frequency is 0.25Hz is sent to electrode system place, down-hole three, wherein a road keeps voltage constant output directly to supply main electrode, and another road supplies two bucking electrodes after voltage-regulation.

Preferably, underground probe comprises inserting tube without magnetic shell, metal without magnetic support, cable interface circuit board, sensor signal processing circuit plate, three axis fluxgate sensors, 3-axis acceleration sensor and inserting tube cable interface; Cable interface circuit board, sensor signal processing circuit plate, three axis fluxgate sensors and 3-axis acceleration sensor are installed in inserting tube without the metal in magnetic shell without in magnetic support; Inserting tube is hermetically-sealed construction without magnetic shell; Underground probe is connected with logging cable by inserting tube cable interface, and utilizes insulating cord to be connected with down-hole three electrode system, and the data that logging cable is used for underground probe to detect are sent to ground signal collecting device; Three axis fluxgate sensors in underground probe are used for detecting the resultant magnetic field numerical value of the low frequency alternating magnetic field that Low-frequency alternating currents that the three axle earth's magnetic fields at underground probe place and accident casing are assembled produces, for determining spacing and the orientation of underground probe and accident casing; 3-axis acceleration sensor is used for detecting the three axle acceleration of gravity numerical value at underground probe place, for determining the placing attitude of underground probe self; The 3-axis acceleration data that 3-axis acceleration sensor detects and the three-axle magnetic field data that three axis fluxgate sensors detect are sent on logging cable by cable interface circuit board by sensor signal processing circuit plate.

Preferably, ground signal collecting device comprises power circuit, cable interface circuit and cable signal decoding circuit; Power circuit is used for providing power supply to cable interface circuit and cable signal decoding circuit; Cable interface circuit is connected with logging cable, convert the high-pressure data signal that logging cable transmits to low-voltage signal, then cable signal decoding circuit is sent to, the Data Analysis sent by underground probe by cable signal decoding circuit out, is transferred to ground relief well by USB interface and is communicated with accident well and detects computing system.

Preferably, ground relief well is communicated with accident well and detects computing system and comprise relief well and be communicated with detection analysis software for calculation and ground display system with accident well, ground relief well is communicated with accident well and detects computing system and utilize the down-hole image data received, detection analysis software for calculation is communicated with accident well by relief well, obtain the relative spatial location data of inserting tube in relief well and accident casing, ground display system is utilized to show in the mode of numeral, word and/or figure, feed back to drilling engineer, instruct creeping into further of relief well.

Preferably, Surface electrode is rectangle metal derby;

Preferably, down-hole three electrode system and underground probe are at least at a distance of 30m.

The method that relief well is communicated with accident well, the relief well based on above-mentioned three electrode systems is communicated with detection system with accident well, and concrete steps are as follows:

Step 1: the hole condition information extracting relief well and accident well: the casing programme of the brill dish level of the mouth coordinate of the well track metrical information of relief well and accident well 6, relief well and accident well, relief well and accident well and EGL, accident well;

Step 2: the hole condition information of the relief well that process is extracted and accident well, obtains the deviational survey data that relief well has bored part and accident well;

Step 3: utilize seven core cable down-hole three electrode system and underground probe to be sent to the bottom of relief well brill part by drilling rod or crawl device equipment, surface power supply equipment provides Low-frequency alternating currents for down-hole three electrode system;

Step 4: ground signal collecting device receives inserting tube detects, the data that reached ground by logging cable, to be communicated with accident well to detect in computing system by being sent to ground relief well after Data Format Transform;

Step 5: utilize the image data of the hole condition information of the relief well after above-mentioned process and accident well, underground probe, work as geomagnetic declination, to be communicated with accident well by ground relief well and to detect computing system, obtain the relative spatial location data of underground probe in relief well and accident casing, utilize ground display system to show in the mode of numeral, word and/or figure;

Step 6: after the relief well obtaining this measuring point place and accident well relative spatial location data, down-hole three electrode system and underground probe are proposed, under enter drill bit and drilling rod, in conjunction with relief well and accident well deviational survey data, continue to creep into relief well to next measuring point place;

Step 7: at this measuring point place, proposes drill bit and drilling rod, repeats above-mentioned step 1 to step 6, until relief well and accident well accurate commutation.

Relief well based on three electrode systems of the present invention is communicated with detection system with accident well and has the following advantages:

1, relief well based on three electrode systems is communicated with detection system with accident well and adopts down-hole three electrode system as current signal emission source, ensure that the electric current flowed out from main electrode can not flow along relief well borehole axis direction, make more electric current flow into stratum then to assemble on accident casing, thus make the inserting tube in relief well relatively larger low frequency alternating magnetic field can be detected, the intensity being simultaneously communicated with the detectable signal of detection system with accident well based on the relief well of three electrode systems also can be controlled by the mode increasing earth's surface current strength, therefore be easy to increase finding range, go for deep-well to be communicated with,

2, based on the relief well of three electrode systems to be communicated with accident well detection system can direct detection relief well shaft bottom to the distance and bearing of accident well, avoid traditional MWD produces accumulated error defect with well depth;

3, to be communicated with the current signal emission source (down-hole three electrode system) of detection system with accident well based on the relief well of three electrode systems and signal sensor (underground probe) is all put in relief well, be therefore applicable to cannot be close near accident well well head operating mode.

4, do not comprise the sensor of very high degree of precision in the underground probe being communicated with detection system with accident well due to the relief well based on three electrode systems, its limit of working temperature can reach 200 DEG C, and therefore this detection system normally can work in deep-well.

Accompanying drawing explanation

Fig. 1 is the structural representation being communicated with detection system based on the relief well of three electrode systems with accident well;

Fig. 2 is the structural representation of surface power supply equipment;

Fig. 3 is the structural representation of down-hole three electrode system;

Fig. 4 is the structural representation of underground probe;

Fig. 5 is the internal circuit schematic diagram of underground probe;

Fig. 6 is the structural representation of ground signal collecting device;

Fig. 7 is columnar electrode electric Field Calculation model;

Fig. 8 is accident casing injects the electric current on stratum response schematic diagram to three electrode systems;

Fig. 9 is relief well and accident well relative position computation model;

In figure: 1, surface power supply equipment, 2, ground signal collecting device, 3, ground relief well is communicated with accident well and detects computing system, 4, Surface electrode, 5, relief well, 6, accident well, 7, down-hole three electrode system, 8, underground probe, 9, Low-frequency alternating currents, 10, alternating magnetic field, 11, seven core cable, 12, insulating cord, 13, logging cable, 14, electrode system cable interface, 15, electrode system metal shell, 16, bucking electrode, 17, insulating trip, 18, main electrode, 19, inserting tube is without magnetic shell, 20, metal is without magnetic support, 21, cable interface circuit board, 22, sensor signal processing circuit plate, 23, three axis fluxgate sensors, 24, 3-axis acceleration sensor, 25, inserting tube cable interface.

Detailed description of the invention

As shown in Figure 1, relief well based on three electrode systems is communicated with detection system with accident well, comprising: surface power supply equipment 1, ground signal collecting device 2, ground relief well are communicated with accident well and detect computing system 3, Surface electrode 4, down-hole three electrode system 7, underground probe 8, surface power supply equipment 1 is positioned near relief well 5 well head, for providing Low-frequency alternating currents for down-hole three electrode system, simultaneously also detecting computing system 3 power for ground signal collecting device 2 and ground relief well are communicated with accident well, Surface electrode 4 is rectangle metal derby, to be connected with the wellhead casing pipe of relief well 5 and contact is good, the output of surface power supply equipment 1 be connected with down-hole three electrode system, input is connected with Surface electrode 1, surface power supply equipment 1 utilizes seven core cable 11 to pass into Low-frequency alternating currents for down-hole three electrode system 7, Surface electrode 4 for receive inject stratum by down-hole three electrode system 7 after the electric current upwards flowed assembled on accident well 6 sleeve pipe and the portion of electrical current injecting stratum by down-hole three electrode system 7, do not assemble on accident well 6 sleeve pipe, to form current loop, down-hole three electrode system enters for 7 times under position will ensure do not have sleeve pipe, thus down-hole three electrode system 7 is directly contacted with relief well 5 borehole wall, so that by the current injection electrode system surrounding formation that receives, this electric current is spherical in shape in stratum to be dispersed, have portion of electrical current to assemble on accident well 6 sleeve pipe simultaneously, formed along sleeve pipe upwards, the Low-frequency alternating currents 9 flowed downward, according to Biot-Savart law, this Low-frequency alternating currents 9 will produce low frequency alternating magnetic field 10 in accident well 6 its vicinity stratum, the magnetic field produced due to the electric current upwards flowed is contrary with the magnetic direction that the electric current flowed downward produces, therefore there is negative function in the magnetic field that the electric current upwards flowed produces to the field signal that underground probe 8 detects, in order to avoid the impact of upwards streaming current, require down-hole three electrode system 7 and underground probe 8 at least at a distance of 30m, be connected with insulating cord 12 between underground probe 8 with down-hole three electrode system 7, and underground probe 8 enters the bottom of relief well 5 under will trying one's best, the magnetic field intensity that the Low-frequency alternating currents of the position of electrode system 7, down-hole three own produces at underground probe 8 place is simultaneously zero, therefore the Weak magentic-field signal that underground probe 8 detects is not affected, underground probe 8 is for the low frequency alternating magnetic field 10 detecting the gravitational field at underground probe 8 place, earth's magnetic field and produced by the Low-frequency alternating currents 9 that accident well 6 sleeve pipe is assembled, require that when measuring underground probe 8 must be static, otherwise the rotation of underground probe 8 or vibrations by cause its cannot accurately detecting to faint field signal, ground signal collecting device 2 is connected with underground probe 8 by logging cable 13, and receives the data that underground probe 8 detects, reached ground by logging cable 13, ground signal collecting device 2 is communicated with to detect in computing system 3 with accident well calculates being sent to ground relief well after the data conversion format received, obtain the underground probe 8 in relief well 5 and the relative spatial location data of accident well 6 sleeve pipe, show in the mode of numeral, word and/or figure.

As shown in Figure 2, surface power supply equipment comprises 380V AC power, step-up transformer, AC/DC converter and frequency controller; First the output of 380V AC power passes through step-up transformer, the voltage that 380V AC power provides is risen to 1000V by step-up transformer, after AC/DC converter, convert the high direct voltage of 1000V to, three electrode systems 7 are exported and can reach the electric current that amplitude is 20A, utilize Single-chip Controlling frequency controller to make it high pressure of 1000V be converted to the alternation square-wave voltage of 0.25Hz frequency, then this alternation square-wave voltage is sent to electrode system place, down-hole three and does again and export further; The input of 380V AC power is connected with Surface electrode.

As shown in Figure 3, down-hole three electrode system 7 is the current signal emission sources being communicated with detection system based on the relief well of three electrode systems with accident well; Down-hole three electrode system 7 comprises electrode system cable interface 14, electrode system metal shell 15, two bucking electrodes 16, two insulating trips 17 and main electrode 18; Down-hole three electrode system 7 is connected with seven core cable 11 by electrode system cable interface 14; Two bucking electrodes 16 and main electrode 18 are cylinder, main electrode 18 is positioned at centre, and length is 0.15m, and two bucking electrodes 16 are arranged in the upper and lower both sides of main electrode 18 symmetrically, the length of bucking electrode 16 is 0.7m, and two bucking electrodes 16 are connected by short-circuit line in inside; Separate with insulating trip 17 between bucking electrode 16 and main electrode 18, the thickness of insulating trip is 0.025m; Two bucking electrodes, 16, two insulating trips 17 are identical with the diameter of main electrode 18.As shown in Figure 2, the amplitude that surface power supply equipment provides is 1000V, frequency is the output being divided into two-way identical polar after the alternation square-wave voltage of 0.25Hz is sent to electrode system 7 place, down-hole three, wherein a road keeps voltage constant to export directly supply main electrode 18, another road supplies two bucking electrodes 16 after voltage-regulation, the current potential on three electrodes is made to be tending towards equal, at this moment the electric potential gradient along down-hole three electrode system 7 longitudinal direction is zero, thus ensure that the electric current flowed out from main electrode 18 can not flow along borehole axis direction, ensure that more electric current flows into stratum and then assembles on accident well 6 sleeve pipe.

As shown in Figure 4, Figure 5, underground probe 8 comprises inserting tube without magnetic shell 19, metal without magnetic support 20, cable interface circuit board 21, sensor signal processing circuit plate 22, three axis fluxgate sensor 23,3-axis acceleration sensor 24 and inserting tube cable interface 25; Cable interface circuit board 21, sensor signal processing circuit plate 22, three axis fluxgate sensor 23 and 3-axis acceleration sensor 24 are installed in inserting tube without the metal in magnetic shell 19 without in magnetic support 20; Inserting tube is hermetically-sealed construction without magnetic shell 19, prevents underground probe 8 surrounding liquid from entering inserting tube, affects circuit working; Underground probe 8 is connected with logging cable 13 by inserting tube cable interface 25, and utilizes insulating cord 12 to be connected with down-hole three electrode system 7, and the data that logging cable is used for inserting tube to detect are sent to ground signal collecting device; Three axis fluxgate sensors 23 in underground probe 8 and the z-axis of 3-axis acceleration sensor 24 and the dead in line of underground probe 8, x-axis and y-axis are perpendicular to the axis of underground probe 8; The x-axis of two sensors is positioned in same plane, and parallel to each other, and the y-axis of two sensors is also positioned in same plane, also parallel to each other; Three axis fluxgate sensors 23 in underground probe 8 are used for detecting the resultant magnetic field numerical value of the low frequency alternating magnetic field 10 that Low-frequency alternating currents 9 that the three axle earth's magnetic fields at underground probe 8 place and accident well 6 sleeve pipe are assembled produces, for determining spacing and the orientation of underground probe 8 and accident well 6 sleeve pipe; 3-axis acceleration sensor 24 is used for detecting the three axle acceleration of gravity numerical value at underground probe 8 place, for determining the placing attitude of underground probe 8 self; The 3-axis acceleration data that 3-axis acceleration sensor 24 detects and the three-axle magnetic field data that three axis fluxgate sensors 23 detect are sent on logging cable 13 by cable interface circuit board 21 by sensor signal processing circuit plate 22.The certainty of measurement of three axis fluxgate sensors 23 reaches 0.01nT, and the certainty of measurement of 3-axis acceleration sensor 24 reaches 0.01g.

As shown in Figure 6, ground signal collecting device 2 comprises power circuit, cable interface circuit and cable signal decoding circuit; Power circuit is used for providing power supply to cable interface circuit and cable signal decoding circuit; Cable interface circuit is connected with logging cable 13, convert the high-pressure data signal of transmission on logging cable 13 to low-voltage signal, then cable signal decoding circuit is sent to, the Data Analysis sent by underground probe 8 by cable signal decoding circuit out, is transferred to ground relief well by USB interface and is communicated with accident well and detects computing system 3.Ground relief well is communicated with accident well and detects computing system 3 and comprise relief well and be communicated with detection analysis software for calculation and ground display system with accident well, ground relief well is communicated with accident well and detects computing system 3 and utilize the down-hole image data received, detection analysis software for calculation is communicated with accident well by relief well, obtain the relative spatial location data of inserting tube in relief well 5 and accident well 6 sleeve pipe, ground display system is utilized to show in the mode of numeral, word and/or figure, feed back to drilling engineer, instruct creeping into further of relief well.

It is as follows that relief well and accident well based on three electrode systems are communicated with detection system operating principle: as shown in Figure 7, down-hole three electrode system 7 is approximately the line electrode of naked ring, current density j is uniformly distributed; Down-hole three electrode system 7 total length is 2L ₀, main electrode 18 total length is 2L, and down-hole three electrode system 7 radius is r ₀, and meet r ₀< < L ₀; It is σ that down-hole three electrode system 7 is positioned at electrical conductivity _eeven stratum in.The mid point getting down-hole three electrode system 7 is the origin of coordinates, simultaneously the dead in line of z-axis and down-hole three electrode system 7.As z=0, the field intensity at distance initial point l place is

$E(l,0)=\frac{I_0}{4\mathrm{\&pi;}{\mathrm{\&sigma;}}_{e}L}\frac{L_0}{l\sqrt{l^2+{L_0}^2}}$

As shown in Figure 8, for the semi-infinite long metal sleeve surrounded by even stratum at distance electrode system 7R place, down-hole three, the electric current that it is assembled is

$I_{\mathrm{\&rho;}}=\frac{{\mathrm{\&sigma;}}_c{r}_c{h}_c{I}_0}{2{\mathrm{\&sigma;}}_{e}L}\frac{L_0}{R\sqrt{R^2+L_0^2}}$

Meet below three assumed conditions prerequisite under: 1) stratum homogeneous isotropism; 2) sleeve pipe endless; 3) radius of sleeve pipe is much smaller than down-hole three electrode system 7 in relief well 5 and the distance between accident well 6 casing axis, and accident well 6 sleeve pipe is r by radius _estratum cylinder substitute, the resistance of this cylinder unit length is identical with accident well 6 sleeve pipe, and this stratum cylinder radius is expressed as

$r_e=\sqrt{\frac{{2\mathrm{\&sigma;}}_c}{{\mathrm{\&sigma;}}_e}{r}_c{h}_c}$

To layer cylinder radius r approx _ebring into the electric current assembled on accident well 6 sleeve pipe is

$I_{\mathrm{\&rho;}}=\frac{r_e^2{I}_0}{4R\sqrt{R^2+L_0^2}}\frac{L_0}{L}$

The mirror position of accident well 6 sleeve pipe is arrived for the origin of coordinates, with the axis of accident well 6 sleeve pipe for z-axis sets up cylindrical coordinate with down-hole three electrode system 7.Low-frequency alternating currents 9 along casing axis z place is

$I\left(z\right)=\frac{L}{L_0}\frac{z/R}{{[1+{(z/R)}^2]}^{3/2}}{I}_{\mathrm{\&rho;}}=\frac{z/R}{{[1+{(z/R)}^2]}^{3/2}}\&CenterDot;\frac{r_e^2}{4R\sqrt{R^2+L_0^2}}{I}_0$

Suppose that Electrodes In Shallow Wells system 7 position A point and underground probe 8 position B point are in same vertical plane, the distance between A, B is d.Well depth, the hole angle of known A, B point are respectively D _a, D _b, α _a, α _b, inclination section radius of curvature is R _z, the average hole angle surveying section is with season then

$\left\{\begin{array}{c}{R}_z=\frac{d}{2\sin {\mathrm{\&alpha;}}_d}\\ R=r+d\sin {\mathrm{\&alpha;}}_c\\ z=d\cos {\mathrm{\&alpha;}}_c\end{array}\right.$

The pass overlapped between tube pitch r to accident well 6 because of the electric current I (z) flowed downward that the accident well 6 sleeve pipe is assembled and underground probe 8 is

$I\left(z\right)=\frac{d\cos {\mathrm{\&alpha;}}_c(r+d\sin {\mathrm{\&alpha;}}_c)}{{(r^2+2\mathrm{rd}\sin {\mathrm{\&alpha;}}_c+d^2)}^{3/2}{[{(r+d\sin {\mathrm{\&alpha;}}_c)}^2+L_0^2]}^{1/2}}\&CenterDot;\frac{r_e^2{I}_0}{4}$

According to Biot-Savart law, the magnetic field intensity of the low frequency alternating magnetic field 10 at underground probe 8 place is

$H=\frac{d\cos {\mathrm{\&alpha;}}_c(r+d\sin {\mathrm{\&alpha;}}_c)}{{(r^2+2\mathrm{rd}\sin {\mathrm{\&alpha;}}_c+d^2)}^{3/2}{[{(r+d\sin {\mathrm{\&alpha;}}_c)}^2+L_0^2]}^{1/2}}\&CenterDot;\frac{{\mathrm{\&mu;}}_0{r}_e^2{I}_0}{8\mathrm{\&pi;r}}$

Thus, after the magnetic field intensity recording the alternating magnetic field 10 that underground probe 8 place is produced by the Low-frequency alternating currents 9 on accident well 6 sleeve pipe, utilize the inversely prroportional relationship between magnetic field intensity H and distance r, the distance between accident well 6 sleeve pipe and relief well 5 underground probe 8 can be obtained theoretically.

As shown in Figure 9, be relief well 5 and accident well 6 relative position computation model.Be n along accident well 6 axis drilling direction ₁, be n along underground probe 8 axis drilling direction ₂, H is the magnetic field intensity of the low frequency alternating magnetic field 10 that in accident well 6 sleeve pipe, electric current I produces at underground probe 8 place, H three axis fluxgate sensor 23x axles and y-axis magnetic-field component in the plane be projected as H _p, this component is respectively H along the component in three axis fluxgate sensor 23x axles and y-axis direction ₁and H ₂, and meet h _dfor H magnetic-field component along the z-axis direction; H and vector r is positioned at same plane, and n ₂perpendicular to this plane.H=H can be obtained thus _p+ H _dh _d=-(H _pn ₁)/(n ₁n ₂)

r/(r·r)＝(2π)(H×n ₁)/μ ₀I

Therefore H is worked as _pafter being recorded by three axis fluxgate sensors 23, substitute into above formula and just can determine H and r uniquely, thus also just determine the spacing of relief well 5 and accident well 6.

Meanwhile, the gravitational vectors at underground probe 8 place measured by 3-axis acceleration sensor 24 is perpendicular to the component G of z-axis _pg is respectively at the component in 3-axis acceleration sensor 24x axle and y-axis direction ₁and G ₂, and meet angle α is component G _pwith x-axis component G ₁between angle, angle β is component G _pwith H _pbetween angle.As shown in Figure 9, cos (alpha+beta)=H ₁/ H _p, sin (alpha+beta)=H ₂/ H _p, cos α=G ₁/ G _p, sin α=G ₂/ G _p, the cosine deriving angle β thus can be expressed as

$\cos \mathrm{\&beta;}=\frac{G_1{H}_1+G_2{H}_2}{G_1^2+G_2^2}\&CenterDot;\frac{\sqrt{G_1^2+G_2^2}}{\sqrt{H_1^2+H_2^2}}$

Therefore, by H that three axis fluxgate sensors 23 and 3-axis acceleration sensor 24 record ₁, H ₂, G ₁and G ₂substitute into above formula and just can try to achieve angle β, thus also just determine the relative bearing of relief well 5 to accident well 6.

The method that relief well is communicated with accident well, the relief well based on above-mentioned three electrode systems is communicated with detection system with accident well, and concrete steps are as follows:

Step 1: the hole condition information extracting relief well 5 and accident well 6; The well track metrical information of relief well 5 and accident well 6; The mouth coordinate of relief well 5 and accident well 6; The brill dish level (KB) of relief well 5 and accident well 6 and EGL (GL); The casing programme of accident well 6;

Step 2: the relief well 5 that process is extracted and the hole condition information of accident well 6, obtain the deviational survey data that relief well has bored part and accident well;

Step 3: utilize seven core cable 11 down-hole three electrode system 7 and underground probe 8 to be sent to the bottom of relief well brill part by drilling rod or crawl device equipment, surface power supply equipment 1 provides Low-frequency alternating currents for down-hole three electrode system 8;

Step 4: ground signal collecting device 2 receives that inserting tube 8 detects, reached ground by logging cable 13 data, to be communicated with accident well to detect in computing system 3 by being sent to ground relief well after Data Format Transform;

Step 5: utilize the image data of the hole condition information of the relief well after above-mentioned process 5 and accident well 6, underground probe 8, work as geomagnetic declination, to be communicated with accident well by ground relief well and to detect computing system 3, obtain the underground probe 8 in relief well 5 and the relative spatial location data of accident well 6 sleeve pipe, utilize ground display system to show in the mode of numeral, word and/or figure;

Step 6: after the relief well obtaining this measuring point place and accident well relative spatial location data, down-hole three electrode system 7 and underground probe 8 are proposed, under enter drill bit and drilling rod, in conjunction with relief well and accident well deviational survey data, continue to creep into relief well to next measuring point place;

Step 7: at this measuring point place, proposes drill bit and drilling rod, repeats above-mentioned step 1 to step 6, until relief well and accident well accurate commutation.

Claims (8)

1. the relief well based on three electrode systems is communicated with detection system with accident well, comprising: surface power supply equipment, ground signal collecting device, ground relief well are communicated with accident well and detect computing system, Surface electrode, down-hole three electrode system, underground probe; It is characterized in that: surface power supply equipment is positioned near relief well well head, for providing Low-frequency alternating currents for down-hole three electrode system, to be also simultaneously ground signal collecting device with ground relief well be communicated with to detect with accident well calculates system power supply; Surface electrode is connected with the wellhead casing pipe of relief well and contact is good, the output of surface power supply equipment be connected with down-hole three electrode system, input is connected with Surface electrode; Underground probe is for the low frequency alternating magnetic field detecting the gravitational field at underground probe place, earth's magnetic field and produced by the Low-frequency alternating currents that accident casing is assembled, ground signal collecting device is connected with underground probe by logging cable, and receives the data that underground probe detects, reached ground by logging cable; Ground signal collecting device is communicated with to detect in computing system with accident well calculates being sent to ground relief well after the data conversion format received, obtain the relative spatial location data of underground probe in relief well and accident casing, show in the mode of numeral, word and/or figure;

Surface power supply equipment comprises 380V AC power, step-up transformer, AC/DC converter and frequency controller; First the output of 380V AC power passes through step-up transformer, the voltage that 380V AC power provides is risen to 1000V by step-up transformer, after AC/DC converter, convert the high direct voltage of 1000V to, three electrode systems are exported and can reach the electric current that amplitude is 20A, utilize Single-chip Controlling frequency controller to make it high pressure of 1000V be converted to the alternation square-wave voltage of 0.25Hz frequency, then this alternation square-wave voltage is sent to electrode system place, down-hole three and does again and export further; The input of 380V AC power is connected with Surface electrode;

Down-hole three electrode system comprises electrode system cable interface, electrode system metal shell, two bucking electrodes, two insulating trips and main electrodes; Down-hole three electrode system is connected with seven core cable by electrode system cable interface; Two bucking electrodes and main electrode are cylinder, and main electrode is positioned at centre, and length is 0.15m, and two bucking electrodes are arranged in the upper and lower both sides of main electrode symmetrically, and the length of bucking electrode is 0.7m, and two bucking electrodes are connected by short-circuit line in inside; Separate with insulating trip between bucking electrode and main electrode, the thickness of insulating trip is 0.025m; Two bucking electrodes, two insulating trips are identical with the diameter of main electrode.

2. the relief well based on three electrode systems according to claim 1 is communicated with detection system with accident well, it is characterized in that: the output being divided into two-way identical polar after the alternation square-wave voltage that the amplitude that surface power supply equipment provides is 1000V, frequency is 0.25Hz is sent to electrode system place, down-hole three, wherein a road keeps voltage constant output directly to supply main electrode, and another road supplies two bucking electrodes after voltage-regulation.

3. the relief well based on three electrode systems according to claim 2 is communicated with detection system with accident well, it is characterized in that: underground probe comprises inserting tube without magnetic shell, metal without magnetic support, cable interface circuit board, sensor signal processing circuit plate, three axis fluxgate sensors, 3-axis acceleration sensor and inserting tube cable interface; Cable interface circuit board, sensor signal processing circuit plate, three axis fluxgate sensors and 3-axis acceleration sensor are installed in inserting tube without the metal in magnetic shell without in magnetic support; Inserting tube is hermetically-sealed construction without magnetic shell; Underground probe is connected with logging cable by inserting tube cable interface, and utilizes insulating cord to be connected with down-hole three electrode system, and the data that logging cable is used for underground probe to detect are sent to ground signal collecting device; Three axis fluxgate sensors in underground probe are used for detecting the resultant magnetic field numerical value of the low frequency alternating magnetic field that Low-frequency alternating currents that the three axle earth's magnetic fields at underground probe place and accident casing are assembled produces, for determining spacing and the orientation of underground probe and accident casing; 3-axis acceleration sensor is used for detecting the three axle acceleration of gravity numerical value at underground probe place, for determining the placing attitude of underground probe self; The 3-axis acceleration data that 3-axis acceleration sensor detects and the three-axle magnetic field data that three axis fluxgate sensors detect are sent on logging cable by cable interface circuit board by sensor signal processing circuit plate.

4. the relief well based on three electrode systems according to claim 3 is communicated with detection system with accident well, it is characterized in that: ground signal collecting device comprises power circuit, cable interface circuit and cable signal decoding circuit; Power circuit is used for providing power supply to cable interface circuit and cable signal decoding circuit; Cable interface circuit is connected with logging cable, convert the high-pressure data signal that logging cable transmits to low-voltage signal, then cable signal decoding circuit is sent to, the Data Analysis sent by underground probe by cable signal decoding circuit out, is transferred to ground relief well by USB interface and is communicated with accident well and detects computing system.

5. the relief well based on three electrode systems according to claim 4 is communicated with detection system with accident well, it is characterized in that: ground relief well is communicated with accident well and detects computing system and comprise relief well and be communicated with detection analysis software for calculation and ground display system with accident well, ground relief well is communicated with accident well and detects computing system and utilize the down-hole image data received, detection analysis software for calculation is communicated with accident well by relief well, obtain the relative spatial location data of inserting tube in relief well and accident casing, utilize ground display system with numeral, the mode of word and/or figure shows, feed back to drilling engineer, instruct creeping into further of relief well.

6. the relief well based on three electrode systems according to claim 5 is communicated with detection system with accident well, it is characterized in that: Surface electrode is rectangle metal derby.

7. the relief well based on three electrode systems according to claim 6 is communicated with detection system with accident well, it is characterized in that: down-hole three electrode system and underground probe are at least at a distance of 30m.

8. the method that is communicated with accident well of relief well, the relief well based on three electrode systems one of the claims 1-7 Suo Shu is communicated with detection system with accident well, and concrete steps are as follows:

Step 1: the hole condition information extracting relief well and accident well: the casing programme of the brill dish level of the mouth coordinate of the well track metrical information of relief well and accident well, relief well and accident well, relief well and accident well and EGL, accident well;

Step 2: the hole condition information of the relief well that process is extracted and accident well, obtains the deviational survey data that relief well has bored part and accident well;

Step 3: utilize seven core cable down-hole three electrode system and underground probe to be sent to the bottom of relief well brill part by drilling rod or crawl device equipment, surface power supply equipment provides Low-frequency alternating currents for down-hole three electrode system;

Step 4: ground signal collecting device receives inserting tube detects, the data that reached ground by logging cable, to be communicated with accident well to detect in computing system by being sent to ground relief well after Data Format Transform;

Step 5: utilize the image data of the hole condition information of the relief well after above-mentioned process and accident well, underground probe, work as geomagnetic declination, to be communicated with accident well by ground relief well and to detect computing system, obtain the relative spatial location data of underground probe in relief well and accident casing, utilize ground display system to show in the mode of numeral, word and/or figure;

Step 6: after obtaining relief well and accident well relative spatial location data, proposes down-hole three electrode system and underground probe, under enter drill bit and drilling rod, in conjunction with relief well and accident well deviational survey data, continue to creep into relief well to next measuring point place;

Step 7: at this measuring point place, proposes drill bit and drilling rod, repeats above-mentioned step 1 to step 6, until relief well and accident well accurate commutation.