CN105974478A - While-drilling VSP measurement sensor mounting equipment and measurement tool - Google Patents

Abstract

The invention relates to a sensor mounting equipment and a measurement tool, belongs to the geophysical exploration technology field and particularly relates to a while-drilling VSP measurement sensor mounting equipment and a measurement tool. The equipment comprises a push-on block driven by a push rod mounted on a VSP measurement tool body, wherein the push-on block comprises a vertically-arranged measurement probe and a sensor mounting body, one end of the sensor mounting body not connected with the measurement probe is provided with a locking ring, and a sensor is fixed in a chamber in the sensor mounting body through the locking ring. The equipment is advantaged in that (1), during measurement, the sensor is driven out through a driving mechanism to couple with a borehole wall, during drilling, the sensor is accommodated in the measurement tool, so strong vibration and impact on the sensor in the drilling process are prevented; and (2), through a sealing ring, slurry is prevented from entering an inner chamber of the push-on block.

Description

A kind of VSP during drilling measures sensor installation device and survey tool

Technical field

The present invention relates to a kind of sensor installation device and survey tool, belong to geophysical exploration technology Field, is specifically related to a kind of VSP during drilling and measures sensor installation device and survey tool.

Background technology

Along with the increasing of oil-gas exploration and development difficulty, vertical seismic profiling (VSP) (Vertical Seismic Profiling, VSP) using value of drilling measuring technology day by day shows especially, especially visits before its stratum Function, investigative range is much larger than other LWD tool.Deep & ultra-deep well Karst cave is accurately fixed The problems such as the card layer of position and high pressure formation are the most still difficult to solve.Such as, relevant data show, in tower Wood area drilling success of northern Tarim basin solution cavity is 59.5%, utilizes VSP during drilling instrument to this area Failure well carries out second positioning, the Drilling ratio of solution cavity can be made to improve to 85%, buried hill depth localization error Less than 1%, significantly reduce drilling risk, save drillng operation cost, and improve drilling well timeliness.

VSP during drilling is Observation Technology of Earthquakes in a kind of well, and it is based on cable VSP technology, by ground The instrument integrations such as seismic wave detection, Data acquisition and storage, on down-hole equipment, are not affecting normal drilling well Under handling situations, measure and record the seismic wave of surface energy source generation in real time after stratum transmission, reflection Signal, thus obtain VSP during drilling data, during by measurement result is walked, polarity, phase place, Amplitudes etc. are analyzed, and obtain the interface depth of drill bit earth layer in front, stratigraphic section and rock properties etc., Its investigative range is up to hundreds of meters before drill bit.Compared with surface seismic, owing to VSP during drilling data are at well Obtaining, seismic propagation path is relatively short, and high frequency signal attenuation is less, therefore, has letter at the end Make an uproar than high, resolution is high, and kinesiology, the dynamic characteristic advantage such as substantially.With normal cable VSP Comparing, VSP during drilling is to measure during drillng operation makes up a joint, and does not disturb drillng operation, accounts for Few with rig time, construction risk is little, and drilling cost is low.Additionally, VSP during drilling can be simultaneously received Upgoing wave and down going wave, can be used to estimate deconvolution operator for surface seismic data；Multi-components VSP during drilling Also can record compressional wave and shear wave, it is achieved multi-wave multicomponent exploration simultaneously.

The key technology of VSP during drilling survey tool is accurately to measure the seismic wave outward journey time, but Down-hole adverse circumstances obtain high precision clock, is to limit VSP during drilling survey tool can actual apply Key factor, after usually requiring that work 200 hours, timing cumulative errors in down-hole are less than 1ms, this for For conventional crystal oscillator, it is difficult to meet the needs accurately measuring seismic travel time.At drilling process Middle downhole sensor device strong vibration to be born, impact, needing to design special mounting structure can meet With the requirement boring instrument.The seismic wave of epicenter excitation after earth-attenuation reaches shaft bottom, VSP survey tool On the coupling effect of sensor and the borehole wall to signal detection by decisive influence, additionally, existingly Face limits with down-hole Real-time Communication Technology factor data transfer rate, it is impossible to quickly effectively obtain underground survey Data.

Sum it up, how to guarantee that VSP seismic wave sensors subtracts with coupling effect, the sensor of the borehole wall Shake structure and high accuracy downhole clock are the main bugbears that VSP during drilling technology needs to overcome.

Summary of the invention

The downhole sensor in drilling process that the present invention mainly solves existing for prior art bears by force After vibration, impact, the coupling effect with the borehole wall is deteriorated and then causes the technology of VSP certainty of measurement step-down to be asked Topic, it is provided that a kind of VSP during drilling measures sensor installation device and survey tool.This VSP during drilling is surveyed Quantity sensor installs equipment and the mounting structure of survey tool employing particular design, when measuring by driving Sensor is released and couples with the borehole wall by motivation structure, is accommodated in survey tool by sensor when creeping into, Thus prevent in drilling process strong vibration and the impact to sensor, and by sealing ring, prevent Mud immerses in the internal die cavity of backup block.

In order to solve the problems referred to above, according to an aspect of the invention, it is provided a kind of VSP during drilling is surveyed Quantity sensor installs equipment, including: by pushing away that the distance rod installed on VSP survey tool body drives By block, described backup block includes vertically disposed measuring probe and sensor fixing body；Described sensor One end that fixing body is not connected with measuring probe is provided with retaining ring, and sensor is fixed by this retaining ring In the cavity within this sensor fixing body.

Optimizing, above-mentioned a kind of VSP during drilling measures sensor installation device, and described sensor is installed It is provided with several on the outer wall of body and seals structure.

Optimizing, above-mentioned a kind of VSP during drilling measures sensor installation device, described sensor defeated Go out holding wire and be connected to measuring circuit by high pressure sealing contact pin.

Optimizing, above-mentioned a kind of VSP during drilling measures sensor installation device, and described sensor is installed The cross section of body and measuring probe is circle, and the cross-sectional diameter of described measuring probe is more than institute State the diameter of sensor fixing body.

Optimizing, above-mentioned a kind of VSP during drilling measures sensor installation device, and described sensor is installed Body is connected with described distance rod.

In order to solve the problems referred to above, according to another aspect of the present invention, it is provided that a kind of VSP during drilling Survey tool, measures sensor installation device including any of the above-described VSP during drilling.

Optimize, above-mentioned a kind of VSP during drilling survey tool, VSP survey tool body is provided with For accommodating the internal die cavity of the backup block of backup block, described backup block inner intracavity is provided with by hydraulic pressure The distance rod that drive mechanism drives.

Therefore, present invention have the advantage that sensor is pushed away by drive mechanism by (1) when measuring Go out and couple with the borehole wall, when creeping into, sensor being accommodated in survey tool, thus preventing and creep into During to the strong vibration of sensor and impact；(2) sealing ring is passed through, it is therefore prevented that mud immerses backup In the internal die cavity of block.

Accompanying drawing explanation

Accompanying drawing 1 is VSP during drilling measuring principle schematic diagram；

Accompanying drawing 2 is VSP during drilling measurement procedure schematic diagram；

Accompanying drawing 3 is VSP during drilling survey tool schematic diagram；

Accompanying drawing 4 is the seismic signal waveform diagram that four component VSP measure；

Accompanying drawing 5 is that VSP during drilling measures sensor installation device schematic diagram；

Accompanying drawing 6 is drill string vibration state oscillogram；

Accompanying drawing 7 is backup mechanism controls schematic diagram；

Accompanying drawing 8 is data carriers structural representation；

Accompanying drawing 9 is the Digital Signals electrical block diagram of data carriers；

Accompanying drawing 10 is data carriers workflow diagram；

Accompanying drawing 11 is synchronizer connection diagram；

Accompanying drawing 12 is that clock synchronization apparatus serial data exports schematic diagram；

Accompanying drawing 13 is clock synchronization apparatus principle schematic；

Accompanying drawing 14 is that underground signal is measured and data storage principle block diagram；

Accompanying drawing 15 is data high-speed playback interface schematic diagram；

Accompanying drawing 16 data high-speed playback program flow chart；

Accompanying drawing 17 data high-speed playback program state diagram.

Detailed description of the invention

Below by embodiment, and combine accompanying drawing, technical scheme is made the most concrete Explanation.

In figure, the borehole wall 101, data carriers 102, VSP survey tool the 103, first bed boundary 104, the second bed boundary 105, focus 106, terrestrial clock synchronizer 107, direct wave 108, First echo the 109, second echo 110, VSP coupling coil 301, signal transmission circuit 302, First hydrophone 303, data communication mouth 304, precision interval clock assembly 305, down-hole governor circuit 306, Z axis cymoscope 307, X-axis cymoscope 308, battery sleeve 309, the second hydrophone 310, seat card machine Structure 311, signal receiving circuit 312, data storage circuitry 313, signal acquisition circuit 314, Y-axis are examined Ripple device 315, measuring probe 501, sealing structure 502, retaining ring 503, cymoscope 504, holding wire 505, sensor fixing body 506, fuel tank 701, electromagnetic valve 702, push action cylinder 703, backup block 704, overflow valve 705, check valve 706, oil pump 707, brushless electric machine 708, VSP survey tool are originally Body 801, slurry channel 802, VSP side coupling coil 803, carry side guiding surface 804, VSP side Guiding surface 805, floating drum 806, control storage circuit 807, carrying device coupling coil 808, magnetic Body 809, Hall element 810, rod-like body 811, docking chamber 812.

Embodiment:

1, system structure

As it is shown in figure 1, the present invention propose four component VSP during drilling measure systems mainly by surface energy source, The groups such as VSP downhole measurement tools, data carriers, terrestrial clock synchronizer and data handling system Become.Wherein down-hole VSP survey tool by be distributed in X, Y, Z axis to three detector array, two Individual hydrophone, circuitry for signal measurement, Data acquisition and storage circuit, signal receive with radiating circuit, System power supply observation circuit, data high-speed download interface and battery sleeve etc. form.Down-hole VSP measures System is as shown in Figure 3.

Down-hole VSP survey tool is the important core part of whole measurement system, and its effect is under production wells Receive seismic signal and automatically extract the preliminary wave time (check shot time), by seismic waveform data It is stored in memorizer to be further analyzed process after Qi Zuaning.VSP during drilling data the most effectively depend on Rely in the precise synchronization of downhole measurement tools Yu ground installation, to this end, underground survey system is selected high-precision The benchmark that records as the time of degree crystal oscillator source, terrestrial clock then using gps clock as reference clock source, Proofreaded a terrestrial clock every 1 second, thus the accuracy of measurement result has been effectively ensured.In order to and Time get underground survey data, in drilling process utilize pump pressure data carriers is pressed into shaft bottom, with VSP survey tool carries out data interaction, quickly reads measurement data and the preliminary wave of each shot point extraction Time, these data are utilized to can get time and depth transfer relation, for being transformed into deeply by time domain seismic profile Degree territory, and can bit location be marked on seismic profile, provide decision-making foundation for drilling engineer. Owing to down-hole VSP survey tool works in the interim that makes up a joint, when down-hole equipment remains static, Surface energy source is i.e. blown out to stratum earthquake-wave-exciting, and three axial cymoscopes simultaneously measure the vertical of earthquake Ripple and shear wave, it is simple to data are processed later and do quantitative analysis.And the earthquake letter that two hydrophone receive Number non-directional, do wave field separation for calculating current seismic velocity and direct wave with transmitted wave.

In VSP during drilling measurement system, being placed by focus near the well head of ground, generally distance well head is about About 50m.Focus is usually controlled source, and it is the focus of a kind of continuous frequency sweep vibration, frequency range Being about 10～100Hz, its advantage is that capacity of resisting disturbance is strong, reproducible.As it is shown on figure 3, ground shake Source produces scanning signal az, this signal az and is measured and record by surface geophone simultaneously.Down-hole is installed on The detector array of VSP during drilling survey tool measures the preliminary wave signal bz that focus transmits through stratum, From focus generation signal az to areal receiver-array to signal bz, the time experienced is tz1.Source signal Az continues downwards to travel to bed boundary can produce reflection wave signal cz and dz.Reflection wave signal cz and Dz by well geophone array received to used be tz2 and tz3 when walking.Owing to ripple signal bz is with anti- Ejected wave signal cz and dz is detected by same detector array and recorded, signal bz, cz and dz It is overlapped mutually and cannot be carried out distinguishing together.Accordingly, it would be desirable to focus is scanned signal az and signal bz, Cz and dz carries out computing cross-correlation process and obtains signal fz.Signal fz obtain in time domain with time tz1, Three relevant for tz2 with tz3 characteristic signals, the most corresponding preliminary wave signal az, reflection wave signal bz And cz.

VSP during drilling tool operation flow process is as in figure 2 it is shown, be described in detail below:

Before brill: downhole tool synchronizes terrestrial clock, and arranges the running parameter of downhole instrument.In brill: 1. Underground signal Acquisition Circuit the most in a dormant state, once automatically detects drillng operation and stops, then Open down-hole sampling configuration, the signal that detection cymoscope receives.If 2. drilling tool remains static, Mud circulation suspends, then excite surface energy source.For avoiding downhole instrument to be activated by drilling tool noise, right The feature of layered halfspace energy is analyzed, and determines and effectively blows out after information, by next big gun Acquired data storage, and first break picking ripple time.The most once automatically detect drillng operation to start, Then preliminary wave time and Wave data are stored in memorizer, wait that data carriers reads, subsequently Open down-hole park mode.4. ground system utilize preliminary wave time timely erection rate model and Time and depth transfer relation, and drill bit is positioned on surface seismic section, in order to carry for formulating informed drilling decisions For foundation.After brill: the whole audience waveform acquisition data in downhole memory derived after trip-out, the later stage does VSP data process.

2, sensor fixing structure

Compared with cable VSP, VSP during drilling measures cymoscope and the hydrophone well to be tolerated that system is used Lower judder and impact, its mounting structure is the most special.

Three geophones are respectively arranged in diverse location on VSP tool body, mutually in X, Y, Z Axially orthogonality relation.To measure outwardly against to the borehole wall from body when measuring in view of cymoscope It is recovered to body after completing, therefore three cymoscopes is separately mounted in the internal die cavity of three backup blocks. Cymoscope owing to using is velocity profile analog detector, and its structure includes column type permanent magnet, up and down Two magnetic boots, coil and coil brace, to the passive spring leaf of coil etc., whole cymoscope It it is a single-degree-of-freedom coasting body.Having two groups of coils mutually rewound on coil brace, external magnetic field exists The noise produced on coil is cancelled out each other.The magnetic boots at magnet steel two ends guarantee that field homogeneity is distributed, and strengthen Magnetic field intensity.When epicenter excitation seismic wave, cymoscope shell produces motion and makes coil in magnetic field In create relative motion, coil cutting magnetic line produces induction electromotive force, and the size of its voltage depends on Speed in motion.Illustrate to the mounting structure of cymoscope with X, as it is shown in figure 5, sensor Installation equipment is by measuring probe 501, sealing structure 502, retaining ring 503, cymoscope 504, signal Several parts compositions such as line 505, sensor fixing body 506.Wherein, sensor installation device is arranged on this On body, the distance rod with hydraulic thrust oil cylinder is connected, and two seals structure effectively prevents mud to immerse, Cymoscope is fixed on the internal die cavity of backup block by retaining ring, and retaining ring uses multiple screws with backup block Fixing, the output signal line of cymoscope is connected to measuring circuit by high pressure sealing contact pin.

VSP tool body top and bottom are respectively arranged with a hydrophone nacelle, have been respectively mounted the first hydrophone 303 and second hydrophone 310, both L separated by a distance, for measuring current interval velocity, obtain Take the information needed for time and depth transfer, because it receives the seismic wave signal around VSP instrument, i.e. annular space mud The fluctuation of middle pressure field, Policy Result is a scalar value, and carrying out wave field separation for the later stage provides necessity Data.Hydrophone is used for measuring the pressure oscillation that seismic wave produces in annular space mud, due to this pressure One scalar of fluctuation, no matter seismic wave all can be sensitive to mud pressure ripple from which direction hydrophone Dynamic, therefore without pushing against the borehole wall, just can measure the seismic wave signal that the coupling of annular space mud comes, water is listened After device is installed to nacelle, uses cover plate to seal, between cover plate and body, use multiple screw to connect firmly, And devise a circular hole on cover plate and mud is introduced to hydrophone sensitive area, pass through ring for reception Empty mud propagates the seismic signal of coming in.

3, drilling tool state-detection

VSP during drilling measurement is to carry out in the interim that makes up a joint, and slush pump quits work, and drilling tool keeps quiet Only state, now, surface energy source is measured to down-hole earthquake-wave-exciting, down-hole VSP instrument guarantee Result accurate and effective.To this end, down-hole control circuit is mounted with two axis accelerometers, for prison in real time Surveying the vibrational state of drilling tool, the drill string vibration signal of measurement, by after band filter, removes signal packet The DC component contained and high-frequency information, only retain medium and low frequency multidate information, thus control circuit examined automatically Measure drilling tool state, it is judged that whether down-hole starts collection storage.Due to the master control selected in VSP instrument Single-chip microcomputer mathematical operational ability is poor, carries out relative complex calculating when needing to take relatively multimachine, can shadow Ring the reliability of whole system work, therefore use better simply algorithm (such as multiplication and division are all as far as possible Use and take advantage of or except the method for 2N realizes).

Onboard accelerometer can the sensitive quasi-periodic vibration longitudinal to drilling tool, and slush pump, rotating disk bore or It is that their the quasi-periodic vibration frequency caused by compound action is not less than 1Hz.Implementation method is as follows:

(1) first the longitudinal acceleration signal that accelerometer detects is carried out bandpass filtering, remove direct current letter Number and high-frequency signal；

(2) accekeration after bandpass filtering is compared with threshold value ± Δ g (± 40mg), determine This value whether zero passage；The most known accekeration is from the occasion of to negative value direction zero passage, acceleration the most subsequently Measured value and+Δ g compare, it is determined whether from negative value on the occasion of direction zero passage；2. when known acceleration Angle value is from negative value on the occasion of direction zero passage, and acceleration measurement the most subsequently and-Δ g compare, really Fixed whether from the occasion of to negative value direction zero passage；

(3) (15 seconds) statistics accekeration zero passage number of times within the time specified；

(4) if statistical value >=30, i.e. think and there is a quasi-periodic vibration, otherwise it is assumed that without quasi-week Phase vibration produces；

(5), in continuous 3 statistics, if number of times >=2 of " statistical value >=30 ", then VSP instrument is allowed It is acquired storage, otherwise forbids that VSP instrument is acquired storage.

(6) threshold value selects.Compare by limited shaft bottom axial acceleration storage data are repeated Analyzing, analog threshold is defined as ± 40mg substantially.According to

$Acc=\frac{2T_1-T_2}{2T_2}\×25=\frac{\mathrm{\Δ}T}{2T_2}\×25$

Wherein, Acc is the accekeration (g) calculated, and T1 is the high impulse relevant with acceleration magnitude Width, T2=12064 is the pulse period unrelated with acceleration magnitude, and Δ T=2T1-T2 is down-hole Single chip computer measurement the intermediate variable calculated.Can be obtained from above

$\mathrm{\Δ}T=\frac{2\×T_2}{25}\×Acc$

When arranging analog threshold for ± 40mg, can obtain digital threshold is Δ T ≈ ± 38.

Embodiment 1:

The duty of slush pump is set automatically by the difference being respectively compared AxRMS and AyRMS and Ath STPUMP。

AxRMS-Ath ＞ 0 or AyRMS-Ath ＞ 0

Then STPUMP=1 (turn on pump)；Otherwise STPUMP=0 (pass pump).

Wherein, AxRMS is X axis vibration sensor root-mean-square value, i.e.

${\mathrm{Ax}}_{RMS}=\sqrt{\frac{\underset{i=1}{\overset{N}{\Σ}}{\left(\frac{Axi}{256}\right)}^2}{N}}=\frac{1}{256}\sqrt{\frac{\underset{i=1}{\overset{N}{\Σ}}{\left(Axi\right)}^2}{N}}$

AyRMS is Y axis vibration sensor root-mean-square value, i.e.

${\mathrm{Ay}}_{RMS}=\sqrt{\frac{\underset{i=1}{\overset{N}{\Σ}}{\left(\frac{Ayi}{256}\right)}^2}{N}}=\frac{1}{256}\sqrt{\frac{\underset{i=1}{\overset{N}{\Σ}}{\left(Ayi\right)}^2}{N}}$

Ath is the artificial comparison threshold value (needing to be obtained by test) arranged, and Axi is X after high-pass filtering Axle (passage 0) vibrating sensor AD sampled value (two bytes have symbol integer number), Ayi is high pass filter Y-axis (passage 1) vibrating sensor AD sampled value (two bytes have symbol integer number) after ripple.N is flat All number of times (being tentatively set to 256), need to open up storage space (2 × 256 according to filtering channel number and N Individual word).

Embodiment 2:

Because Axi (or Ayi) is that two bytes have a symbol integer number, and Axi ÷ 256 (or Ayi ÷ 256) Result actually take the high byte (being designated as AxiHGH and AyiHGH respectively) of Axi (or Ayi), So need the memory space opened up can reduce half (2 × 256 bytes).

AxRMS is X axis vibration sensor root-mean-square value, i.e.

${\mathrm{Ax}}_{RMS}=\sqrt{\frac{\underset{i=1}{\overset{N}{\Σ}}{\left({\mathrm{Axi}}_{HGH}\right)}^2}{N}}$

AyRMS is Y axis vibration sensor root-mean-square value, i.e.

${\mathrm{Ay}}_{RMS}=\sqrt{\frac{\underset{i=1}{\overset{N}{\Σ}}{\left({\mathrm{Ayi}}_{HGH}\right)}^2}{N}}$

The vibration damping of circuit board and the decay of high pass filter cause AxiHGH and AyiHGH to be often 0 (the most dynamic State accekeration is always less than 1g), now automatic decision may lose efficacy, and needs to be tested by test Card.Described drilling tool condition detection method has been carried out verification experimental verification, actual result as shown in Figure 6, Wherein surface mud pump work frequency is about 1.5Hz, and the slush pump operating frequency frequency of calculating (is removed narrow Before pulse) it is 1.67Hz, the slush pump operating frequency frequency (after removing burst pulse) of calculating is 1.67Hz, Visible detection result can be as effective criterion of down-hole equipment state.

4, backup mechanism

Seismic wave measurement data is the most effectively had to closing weight by the coupling effect between cymoscope and the borehole wall The impact wanted.When drillng operation suspends (making up a joint), it is static that electric circuit in well detects that drilling tool is in State, control circuit starts brushless electric machine, drives oil pump to rotate the hydraulic oil produced, after check valve Enter push action cylinder, thus promote drive rod will to carry the backup block backup of cymoscope to the borehole wall, motor Quit work, owing to the hydraulic oil in push action cylinder is without bleed-off circuit, backup after running certain time interval T Mechanism is in packing state.Now VSP instrument in down-hole just starts gather seismic signal and store measurement Data, wait until to gather after storage completes, and send control command and allow electromagnetic valve action, and hydraulic oil is quick Releasing to fuel tank, backup block is regained the most rapidly, terminates this signal measurement.

As it is shown in fig. 7, sensor backup mechanism by fuel tank 701, electromagnetic valve 702, push action cylinder 703, Several parts such as backup block 704, overflow valve 705, check valve 706, oil pump 707, brushless electric machine 708 Composition, wherein, fuel tank 701 is bladder-type cell.Below control principle is described in detail: oil pump 707 produce hydraulic oil under motor 708 drives, and output to check valve 706 connects push action cylinder 703, In view of being likely encountered bigger counteracting force during backup, oil cylinder is caused to build the pressure and damage hydraulic pressure system System, at an indirect overflow valve 705 of oil cylinder 703 entrance and fuel tank 701, effectively protects hydraulic pressure system System safety.The effect of electromagnetic valve 702 is after measurement terminates, and provides one quickly for push action cylinder Current by pass, it is ensured that thrust block pad can be regained smoothly.Brushless electric machine 708 uses soft starting mode to control System, it is adjusted accelerator to be first even acceleration, runs with constant speed, its benefit after reaching setting speed It is that electric motor starting rush of current is less, is that reliability is high.

5, data carriers

Current more advanced mud-pulse transfer rate also can only achieve 3～5bps, and other are such as intelligent drilling rod Transmission technology, although transfer rate reaches as high as 100kbps, but its reliability when heavy duty service is relatively Low, relatively costly, whole system complexity is huge, is not suitable for real-time Transmission VSP during drilling all-wave number of fields According to.Owing to the all-wave data of VSP during drilling systematic survey are temporarily stored in downhole memory, it is impossible to enter Row is uploaded in real time, can only be derived again, largely limit VSP during drilling system after by the time pulling out of hole The feature that system is measured in real time.Additionally, terrestrial clock is separate with downhole clock, the two opens in synchronization Each self clock after dynamic, owing to downhole clock receives high temperature impact, causes the long-time stability of downhole clock All decrease compared with terrestrial clock, and high-precision underground clock is the pass of whole VSP during drilling system Key, usually require that after 200 hours down-hole VSP instrument and timing error between terrestrial clock want Less than 1ms, therefore use data carriers will to reach VSP instrument under the temporal information of ground precise synchronization, Can effectively eliminate the timing error that downhole clock produces, thus improve borehole seismic wave measurement precision.

In order to obtain required down-hole VSP data in time, the present invention proposes a kind of novel number According to timesharing carrying device.It has two major functions, and one is that down-hole VSP data are read in timesharing, and two are Carry precise time information, for proofreading the error that down-hole VSP clock produces.As shown in Figure 8, This data carriers is cylindrical-shaped structure, mainly by VSP survey tool body 801, slurry channel 802, VSP side coupling coil 803, carry side guiding surface 804, VSP side guiding surface 805, floating drum 806, Control storage circuit 807, carrying device coupling coil 808, magnet 809, Hall element 810, Several parts compositions such as rod-like body 811, docking chamber 812.The wherein control of data carriers and storage electricity Road as it is shown in figure 9, mainly by digital signal controller, signal transmitter unit, signal modulating unit, Transmitting coil, signal receiving unit, receiving coil, signal demodulation unit, hall signal detector unit, Memory cell and low-tension supply composition.Coupling coil is wound on magnetic core, in order to improve signal coupling Close effect and high-permeability material selected by message transmission rate magnetic core, it is possible to achieve and between VSP instrument High-speed data be wirelessly transferred.Immersing in view of mud, coil surface is provided with protection sleeve.In order to Ensureing data transmission bauds and reliability, the clearance control between two coupling coils is within 1mm. Control to be arranged on data carriers body interior with storage circuit, use set of cells as power supply.Data Carrier detects whether hall signal is high level in real time, thus controls whether to carry out data interaction.Number It is operated under holotype according to carrier, controls data transfer direction, and VSP tool work is from pattern. There is identical inclined-plane guide frame on the VSP tool body docked with data carriers, and pass at Hall Sensor just to position permanent magnet is installed, its objective is to be butted into VSP instrument at data carriers After merit, under the action of a magnetic field of permanent magnet, data carriers is able to detect that a high level signal, As whether docking successful status signal, when this status signal is only for high level, data interaction is Carry out.If in data transmission procedure, mated condition signal step-down, then preserve this digital independent knot Really, waiting state signal continues to read data when being high, it is achieved that data breakpoint resumes, thus ensures The reliability of each data interaction.Owing to the seat card on VSP instrument uses inclined-plane guide-localization, therefore Devise 6 pod apertures in instrument upper end, slurry channel has been effectively ensured enough water conservancy diversion cross sections, Under mud pressure effect, guarantee that data carriers can reliably dock with VSP instrument.

The concrete workflow of data carriers is as shown in Figure 10.Now to this data carriers operation principle Do following detailed description: when needs obtain down-hole VSP data, start data carriers work, with When terrestrial clock carries out synchronization pair, and set running parameter, put into drilling tool central ports, on ground Under mud pump function, it is pressed into shaft bottom, owing to all having guiding on VSP instrument and data carriers Inclined-plane, therefore carrier can be automatically positioned VSP tool seat card, the permanent magnet on VSP tool body produces Under raw the action of a magnetic field, Hall element one high level signal of output on data carriers, control Once detecting this level with storage circuit is height, represents that data carriers docks successfully with VSP instrument, Beginning through respective coupling coil and carry out data interaction, if controlling with storage this level of electric circuit inspection being Low, then it represents that to dock unsuccessfully, do not communicate with VSP instrument.After data carriers successfully docks, Precise time this moment is sent to VSP instrument by data carriers, in order to eliminate VSP clock in down-hole The timing error produced because of its Long-term stability difference under hot environment, reads data each time according in advance The data length first set and baud rate are carried out, and after pending data has read, data carriers then stops Only read, and the data received are stored.When ground, slush pump quits work, data carriers By automatic emersion to well head, then taken instrument shelter, downloaded the data read.

6, clock synchronization apparatus

VSP during drilling measures system by downhole data collecting unit and ground auxiliary signal collecting unit two Being grouped into, the clock synchronization accuracy of two unit requires the highest (< 1ms), and ground synchronous device uses GPS is as reference clock source, and its accuracy of timekeeping is up to 1us level.On the one hand ground synchronous device is wanted and well Lower measuring unit carries out clock synchronization, on the other hand then wants real time record focus to blow out the moment, in order to obtain Take the underground survey data that each big gun is corresponding.Additionally, need acquisition scans signal wave for controlled source Shape, for data correlation process.Usually require that ground synchronous device and Seismic Source System time synchronisation precision The highest, reach tens us levels.

As shown in figure 11, controlled source synchronous control system includes two parts, i.e. coding unit and decoding Unit, the synchronizer of usual ground and focus coding unit are positioned at instrument shelter, and decoding unit is then at well Field is blown out a little, uses therebetween wired or wireless mode to connect.Ground GPS synchronizer and focus Controller is that 4 line systems connect, and wherein start pulse signal is and GND mono-group, scanning signal and GND Being one group, often group signal is a pair twisted-pair feeder, length about about 2m, and two groups of holding wires are bare wire, Need mating connector voluntarily.Focus triggers the positive pulse that signal is amplitude 2～5V, meets Transistor-Transistor Logic level Specification, its driving force is up to 20mA.Scanning signal frequency is 6～125Hz, and signal amplitude is 0～12V, Reach maximum after 0.5s, be constant amplitude sinusoid swept-frequency signal afterwards.Scanning signal is continuous signal, Focus often triggers and the most then sends a string frequency sweep ripple, and conventional frequency scope about 8～96Hz, sweep time is about 8～20s, select according to concrete geological conditions.Ground synchronous device using gps clock as reference, With underground survey system precise synchronization timing, real time record surface energy source is blown out the moment, is accurate to 0.01ms, gathers storage scanning signal waveform and does rear cross correlation process, sampling interval 1ms, data length For 24Bits.

Gps satellite can provide accurate UTC (universal time coordinated) in the world Temporal information.GPS time service module is utilized to receive the UTC time information of satellite, by its interface with synchronization In device, the communication serial port of digital signal processor is connected, and the GPS time information of reception is reached number Word signal processor, is then processed the UTC time information received by software, same in order to correct The precise time of step device.As shown in figure 13, ground GPS synchronizer specifically includes that at digital signal Reason device, GPS time service module, nonvolatile memory cell, LCD MODULE, lock-out pulse export, touch Signalling detector unit, button detector unit, communication interface and power circuit etc..This device is with GPS Time service module is core, gets absolute time information (year accurately by serial ports from GPS time service module / the moon/day/time/point/second), and calibrate a clocking value every 1s (PPS), ground has been effectively ensured The accuracy of timekeeping of synchronizer.

In order to ensure down-hole and ground timing precise synchronization, after downhole instrument powers on and has configured parameter, Ground synchronous device, in whole moment second, sends synchronous enabling signal to downhole instrument so that it is start working； When instrument pull out of hole after, ground installation again in whole moment second, send synchronization end signal to downhole instrument, Make it quit work.By the time of recorded downhole with ground timing as reference, available timing error, Data processing stage is eliminated.After VSP instrument enters well, drilling tool is made to remain static when making up a joint, Surface energy source starts to excite blows out, and energy source controller produces and triggers signal simultaneously, and GPS synchronizer is real-time Record trigger signal pulse rising edge time, for accurately finding the well that this big gun seismic signal is corresponding Lower measurement data, and by record trigger the moment according to blow out order preserve into the literary composition with time marking Part.The feature excited for controlled source frequency sweep, synchronizer needs to gather storage scanning signal waveform, For later data relevant treatment, after determining scanning signal parameter according to field geology conditions, triggering Signal produces moment (rising edge) acquisition scans signal, and stores into the digital wave with time marking Shape file.The file of GPS synchronizer record is uploaded to computer by RS-485 bus, for the later stage Carry out the data that data processing and inversion decision-making provides necessary.

7, signals collecting stores with data

As shown in figure 11, the signal acquisition circuit that the present invention proposes controls 24 ADC pair, down-hole 5 passage X, Y, Z axis geophone signal and two hydrophone signals are measured in real time, and by its collection result It is stored in serial sram chip array and caches.In circuit, 24 ADC of high accuracy are that TI company is high Authenticity product ADS1278HT, its high sampling rate is sufficient for up to 144KSPS, 70KHZ bandwidth 10～the 100HZ swept-frequency signals that surface controllable focus produces gather requirement, when it is operated in high-resolution During pattern, its signal to noise ratio can reach 111db.After cymoscope and hydrophone detect seismic signal, point Do not amplified through preposition modulate circuit, in order to meet ADS1278HT and carry out analog digital conversion requirement. Preamplifier uses low-power consumption, rail-to-rail, programme-controlled gain differential amplifier THS4521.Digital signal Controller uses the dsPIC33FJ128MC710A of Microchip company as main control chip control ADS1278HT is operated in synchronous acquisition mode, is read the data gathering conversion by SPI port, and will These data are by caching in spi bus write sram chip array.Sram chip array uses 8 Sheet 1Mbit high temperature sram chip cascades, and memory capacity is up to 128KB, when meeting seismic first breaks Between automatically extract with real time data processing needed for buffer memory capacity requirement.

As shown in figure 14, data storage circuitry is used for storage well lower sensor (cymoscope and hydrophone) The seismic signal waveform detected, carries out data readback, in order to be further VSP in well site after trip-out Data process&analysis.Owing to the sampling interval of seismic signal is 1ms, data length is 24Bit, 5 channel acquisition data volume once is 15 bytes, and therefore, VSP during drilling measures system down-hole number Need to reach more than 2GB according to memory capacity.Main control chip dsPIC33FJ128MC710A is for storage Chip array be written and read control, and receive by signal acquisition circuit main control chip send data cached. The instructions such as the erasing of storage array, read/write address are arranged are sent out by RS485 bus by ground-based computer After delivering to main control chip, then controlled corresponding NORFLASH storage chip by main control chip.Data store Circuit is carried out memory chip array management by with a piece of high temperature CPLD chip, and this chip uses VERILOG It is programmed by language, it is achieved 5 input 32 output control functions, for 32 high temperature NORFLASH Storage chip carries out sheet choosing management.Main control chip is responsible for collaborative CPLD and NORFLASH by spi bus Chip operation, completes the SPI Read-write Catrol to every a piece of NORFLASH chip.Storage chip array is adopted With the 64MB high temperature NORFLASH storage chip of magnesium light company, whole memory element is by 32 64MB Storage chip cascade composition, total memory capacity is up to 2GB.VSP during drilling measures system requirements every passage letter It is 1ms that number collection meets the sampling interval, and data length is the requirement of 24Bit.According to 5 channel acquisition meters Calculate, 2GB memory capacity can meet four component VSP during drilling survey tools work continuously 200 hours required Memory space.

8, data high-speed playback

When VSP during drilling measures system for field application, it is desirable to quick-downloading downhole tool storage after trip-out Data, carry out rate pattern correction in time and data process, and mark bit location in seismic profile On, provide decision-making foundation for drilling engineer.The VSP data capacity gathered due to down-hole is relatively big, because of This, data readback speed is particularly important, and the conventional data download interface with brill instrument generally uses RS485 Bus, its message transmission rate is relatively low, and the time obtaining data needs is longer, thus affects brill Well operations progress.And USB2.0 interface is a kind of to apply the new interface technology in computer realm, tool Having transmission speed faster, theoretical transmission speed is 12Mbps, supports hot plug and connects multiple equipment Feature, be the most used widely in all kinds of external equipments.In order to improve to greatest extent Data speed of download, the present invention is utilized USB to turn SPI interface circuitry and is directly read by spi bus and deposit Memory data, and without digital signal controller transfer, it is achieved that the high speed of Large Copacity VSP data Download.

As shown in figure 15, the present invention design data readback circuit specifically include that FPGA controller, two SRAM, USB2.0 controller CY7C68013A of sheet 512KB, SPI interface, 48MHz crystal oscillator and Computer etc..Data readback speed can reach 32MB per second, and FPGA controller is used for reading Large Copacity number According to the data of storage circuit, and be cached in the SRAM of 512KB, two panels SRAM as data FIFO, I.e. after a piece of SRAM storage is full, it is sent to ground-based computer by USB2.0 chip CY7C68013A, and Fpga chip then continues read memorizer and be cached to other a piece of SRAM memory, same after storage is full Sample is sent to ground-based computer by USB2.0 chip CY7C68013A.Two panels SRAM is grasped with " table tennis " Operation mode works, and data transmission bauds is greatly improved.

Below in conjunction with Figure 16, the concrete program circuit of data high-speed downloads is described in detail.On After electricity, first FPGA firmware framework arranges all internal state variable, then calls user's initialization function TD_Init().After to be returned, firmware framework will initialize USB interface becomes the state not configured, And enable interruption.Now, and then in 1s, firmware starts re-enumeration (ReNumerate), And starting task distributor, this task distributor will perform following work with being sequentially repeated.

1) poll function TD Poll () is called.

2) Standard Device request has been detected whether, if receive SETUP bag.If it has, it will solve Analysing the command request received and responded, if transmission data command, FPGA controller is by right SRAM carries out FIFO read-write operation.

3) decide whether to report that USB hangs up event.If USB to be reported hangs up event, then call Function TD_Suspend, if successfully returning, then tests wake events.If being not detected by waking up thing up Part, it will be put into FPGA controller in suspending mode.When reply event is detected, will adjust With function TD_Resume (), and rebound step 1).

Below the concrete program state of data high-speed downloads is described in detail.FPGA controller is read Write the program state figure of SRAM as shown in figure 17, respectively corresponding fifo interface data output control and The input of fifo interface data controls.

1) fifo interface data output routine flow process

IDLE: event of reading produces, and enters STATE1；STATE1: enable SLCS, determine from FIFO Read address, if FIFO non-NULL, ensureing after fifo address the most stably 25ns occurs, entering Enter STATE2, otherwise rest on STATE1；After one clock cycle of STATE2: time delay, enable SLOE, is driven into the data in internal FIFO on data/address bus, enters STATE3；STATE3: After one clock cycle of time delay, enable WRREQ, the data on data/address bus write in Ping-pong FIFO, Enter STATE4；After one clock cycle of STATE4: time delay, enable SLRD, simultaneously SLRD letter Number to ensure the time of setting up and retention time requirement, delay next address through tXFD Data fifo is driven on data/address bus, enters STATE5；STATE5: if still having data to read, Enter STATE2, otherwise enter IDLE.

2) fifo interface data entry program flow process

IDLE: event of writing produces, and enters STATE1；STATE1: enable SLCS, determine from FIFO Address, if FIFO is non-full, after ensureing that EZ-USB fifo address the most stably 25ns occurs, Enter STATE2, otherwise rest on STATE1；After one clock cycle of STATE2: time delay, make Energy RDREQ, drives in the data to data bus in Ping-pong FIFO, and ensures the minimum of tSFD Requirement, enters STATE3；After 2 clock cycle of STATE3: time delay, enable SLWR, simultaneously Ensure time of setting up and the retention time requirement of SLWR signal, at the rising edge of IFCLK, data quilt Write is from FIFO, and the flag bit of FIFO is updated delaying through tXFLG, enters STATE4； STATE4: if submitting to from last group data that the data of FIFO are Ping-pong FIFO, then make Energy PKTEND, simultaneously under conditions of meeting its foundation, retention time, the rising edge at IFCLK carries Hand over last to organize data, enter STATE5；STATE5: if still having data to read, enter STATE2, otherwise enters IDLE.

Specific embodiment described herein is only to present invention spirit explanation for example.The present invention Person of ordinary skill in the field described specific embodiment can be made various amendment or Supplement or use similar mode to substitute, but without departing from the spirit of the present invention or surmount appended power Scope defined in profit claim.

Although the most more employ the borehole wall 101, data carriers 102, VSP survey tool 103, First bed boundary the 104, second bed boundary 105, focus 106, terrestrial clock synchronizer 107, Direct wave the 108, first echo the 109, second echo 110, VSP coupling coil 301, signal are sent out Radio road 302, the first hydrophone 303, data communication mouth 304, precision interval clock assembly 305, down-hole Governor circuit 306, Z axis cymoscope 307, X-axis cymoscope 308, battery sleeve 309, the second hydrophone 310, seat mechanism for card 311, signal receiving circuit 312, data storage circuitry 313, signals collecting electricity Road 314, Y-axis cymoscope 315, measuring probe 501, sealing structure 502, retaining ring 503, detection Device 504, holding wire 505, sensor fixing body 506, fuel tank 701, electromagnetic valve 702, thrust oil Cylinder 703, backup block 704, overflow valve 705, check valve 706, oil pump 707, brushless electric machine 708, VSP survey tool body 801, slurry channel 802, VSP side coupling coil 803, carry side and guide tiltedly Face 804, VSP side guiding surface 805, floating drum 806, control storage circuit 807, carrying device couples Coil 808, magnet 809, Hall element 810, rod-like body 811, term such as docking chamber 812 etc., But it is not precluded from using the probability of other term.Use these terms to be only used to more easily to retouch State and explain the essence of the present invention；Being construed as any additional restriction is all and the present invention Spirit is contrary.

Claims (7)

1. a VSP during drilling measures sensor installation device, it is characterised in that including: surveyed by VSP The backup block that the distance rod installed on amount tool body drives, described backup block includes vertically disposed survey Amount probe (501) and sensor fixing body (506)；Described sensor fixing body (506) not with survey One end that amount probe (501) is connected is provided with retaining ring (503), and sensor (504) passes through this lock Tight ring (503) is fixed in the cavity that this sensor fixing body (506) is internal.

A kind of VSP during drilling the most according to claim 1 measures sensor installation device, its feature It is, the outer wall of described sensor fixing body (506) is provided with several and seals structure (502).

A kind of VSP during drilling the most according to claim 1 measures sensor installation device, its feature Being, the output signal line (505) of described sensor (504) is connected to by high pressure sealing contact pin Measuring circuit.

A kind of VSP during drilling the most according to claim 1 measures sensor installation device, its feature Being, the cross section of described sensor fixing body (506) and measuring probe (501) is circle, And the cross-sectional diameter of described measuring probe (501) is more than described sensor fixing body (506) Diameter.

A kind of VSP during drilling the most according to claim 1 measures sensor installation device, its feature Being, described sensor fixing body (506) is connected with described distance rod.

6. a VSP during drilling survey tool, it is characterised in that include described in any of the above-described claim VSP during drilling measure sensor installation device.

A kind of VSP during drilling survey tool the most according to claim 6, it is characterised in that VSP The internal die cavity of the backup block for accommodating backup block it is provided with, in described backup block on survey tool body The distance rod driven by hydraulic drive mechanism it is provided with in portion's die cavity.