Controllable dynamic calibration device and method for natural gamma detector

Abstract

The invention discloses a controllable dynamic scale device and method for a natural gamma detector. The controllable dynamic scale device comprises a system rack, a scale source box, a track system, a lifting mechanism, a control system and an acquisition system, the track system is fixed on the system rack, and the scale source box is arranged on the track system for sliding connection; lifting mechanisms are installed on the two sides of the scale source box and used for supporting a scale instrument. The control system is connected with the track system and a motor driving system of the lifting mechanism, and the acquisition system is connected with a calibrated instrument. By controlling the scale device to move on the track at a constant speed, the dynamic detection state of the logging instrument penetrating through the bottom layer underground is simulated, and accurate scale constants of the gamma probe at different speed measurement are obtained. The invention relates to a natural gamma scale theory, a scale system design scheme and a mechanical structure design and control method.

Description

Technical Field

[0001] The invention belongs to the technical field of petroleum well logging, and in particular to a controllable dynamic calibration device and method for a natural gamma detector. Background Art

[0002] Natural gamma logging is a method of measuring the natural gamma ray intensity of rock formations along the wellbore, and is a commonly used means of formation detection in the field of oil exploration. Gamma rays in the formation reach the detector through the mud, and generate fluorescence after entering the NaI crystal in the probe, which is converted into an electrical pulse signal through the multiplier tube. In the actual exploration process, the natural gamma logging instrument passes through the formation at a fixed speed, records the pulse signals at different times, and converts them into gamma intensities at different formation depths through preprocessing, forming a natural gamma curve to complete gamma data collection.

[0003] The maximum measurement speed of natural gamma is usually limited to 600m / h. Exceeding this speed will cause the statistics of the natural gamma curve to fluctuate dramatically. However, in the actual logging instrument string, the measurement speed of conventional acoustic wave, radioactive, and electromagnetic induction instruments can reach 900m / h or even higher. In order to reduce the data fluctuations of the natural gamma curve caused by the change in measurement speed, the Kalman filter data preprocessing method is used to introduce the logging speed factor into the gamma crystal calibration system, establish a mathematical model of instrument measurement speed and natural gamma count rate, and numerically balance the radioactive ray count rate collected by the sensor at different measurement speeds in the same formation. The comprehensive calibration coefficient K of the introduced natural gamma probe V , B V :

[0004] K V =a×V+b,B V =c×V+d (a, b, c, d are constants, V is the detection speed).

[0005] K V , B V Both are directly related to the actual velocity V. Establishing an accurate relationship model between the calibration coefficient and the velocity is the basis for the accuracy of gamma measurement. Therefore, the detector of the gamma logging instrument needs to be calibrated regularly and the detection constant value needs to be corrected to maintain the measurement accuracy. The main working method of this type of calibration device is to put the scale box on the outside of the instrument for calibration, use a scale frame to fix the scale or manually hold a portable scale box for calibration, which has the following problems:

[0006] When using a fixed scale box for calibration, it is impossible to establish a comparison relationship between the speed measurement and the comprehensive calibration coefficient. Only one set of coefficients can be used in the preprocessing of different speed measurement data, which affects the accuracy of gamma value calculation;

[0007] Using human assistance to push the scale box to move usually only blurs the scale and cannot provide accurate scale speed. The process speed range is small and the movement stability and uniformity are poor.

[0008] Conventional calibration boxes can only select a single radiation source (yellow cloth, calibration tile, natural stone, etc.) and cannot be replaced;

[0009] The scale device has poor adaptability to instruments of different pipe diameters, has no adjustment capability, or requires a special bushing to keep the instrument centered on the scale.

[0010] In summary, in the prior art, in the preprocessing of natural gamma logging data, there is a problem that the comprehensive calibration coefficient is incomplete, resulting in large fluctuations in the natural gamma curve during high-speed logging. Summary of the invention

[0011] In order to solve the problems existing in the prior art, the present invention provides a controllable dynamic calibration device and method for a natural gamma detector, which controls the calibration device to move at a constant speed on a track, simulates the dynamic detection state of a logging instrument passing through the bottom layer in the well, and obtains accurate calibration constants of the gamma probe at different measuring speeds. The present invention relates to the natural gamma calibration theory, the calibration system design scheme, the mechanical structure design and the control method.

[0012] To achieve the above object, the present invention provides the following technical solutions:

[0013] A controllable dynamic calibration device for a natural gamma detector, comprising a system stand, a calibration source box, a track system, a lifting mechanism, a control system, and a collection system;

[0014] The track system is fixed on the system stand, and the calibration source box is arranged on the track system for sliding connection; lifting mechanisms are installed on both sides of the calibration source box, and the lifting mechanisms are used to support the calibration instrument; the control system is connected to the track system and the motor drive system of the lifting mechanism, and the acquisition system is connected to the calibrated instrument.

[0015] Preferably, the system stand comprises an outer frame and rollers; a track system is installed on the top of the outer frame, and rollers are installed on the bottom of the outer frame.

[0016] Preferably, the calibration source box comprises a box base, a support cage, a calibration source and a box cover;

[0017] The box base and the box cover are buckled together to form a closed cylinder, a support cage is installed inside the closed cylinder, a calibration source is supported on the support cage, and the calibration source cooperates with the calibration instrument.

[0018] Preferably, the track system includes a motor, a coupling, a pulley set, a linear module, a slide, and a stop block;

[0019] The front of the linear module is a slide track and a pulley groove. Motors are fixed at both ends of the linear module. The motor drives the coupling to rotate in coordination with the pulley group. The pulley group drives the belt to move inside the pulley groove. The belt is connected to the slide, and the slide is slidably connected to the slide track.

[0020] Furthermore, stop blocks are installed at both ends of the linear module, and the stop blocks are made of rubber material.

[0021] Furthermore, a fixing groove of the calibration source box is arranged on the slide, and the fixing groove cooperates with the boss of the box base to increase the thrust of the calibration source box during the forward and backward movement.

[0022] Preferably, the lifting mechanism includes a motor, a coupling, a lead screw, a fixed pedestal, a slider, a cross arm, a V-shaped fixed pedestal, and a track connection base;

[0023] The track connection base is installed on the track system, and the track connection base is slidably connected along the track system. A motor is installed on the side of the track connection base, and the output shaft of the motor is connected to the screw through a coupling. A slider is connected to the screw, and the slider is connected to the bottom of the cross arm. The motor rotates the coupling to drive the screw to move the slider back and forth, so that the cross arm can be lifted and lowered; a V-shaped fixed platform is installed on the top of the cross arm, and the V-shaped fixed platform is used to support the calibration instrument.

[0024] A method for controlling dynamic calibration of a natural gamma detector, characterized in that a device for controlling dynamic calibration of a natural gamma detector based on any one of the above-mentioned devices comprises:

[0025] Hang the calibration source box on the track system and open it, place the instrument to be calibrated on the lifting mechanism and close the calibration source box, then adjust the lifting mechanism to make the central tube of the instrument to be calibrated and the calibration source box concentric;

[0026] The driving track system drives the calibration source box to slide and test the motion state, opens the connector of the calibrated instrument for communication connection, and completes the calibration preparation work;

[0027] At the beginning of the calibration process, the control system drives the track system to move the calibration source box, which passes through the instrument probe at different speeds set according to the calibration requirements, records the gamma sensing data in groups, completes data preprocessing based on the measured results, and obtains the calibration constant values ​​under different speed measurement states; at the end of the calibration, open the calibration source box and reset the lifting mechanism, disconnect the instrument communication and remove the calibrated instrument, remove the calibration source in the calibration source box and store it in accordance with the specifications.

[0028] Preferably, the calibration constant and speed measurement relationship model formula is:

[0029] T 源 =KV T 测 +B V =(a×V+b)T 测 +(c×V+d)

[0030] Where, T 源 is the gamma value of the scale box, T 测 is the gamma measurement value of the instrument probe, K V , B V is the scale constant; T 测 is the gamma measurement value of the instrument probe at each speed moment; V is the measured speed; a, b, c are all constants, and d is the floating deviation of the overall adjustment curve.

[0031] Compared with the prior art, the present invention has the following beneficial technical effects:

[0032] The present invention provides a controllable dynamic calibration device for a natural gamma detector. Through a controllable dynamic calibration method and a calibration device, a comprehensive calibration coefficient of a gamma probe in different velocity measurement states is obtained. On the one hand, the calculation accuracy of the gamma detection data preprocessing process is improved, and a more scientific and reliable analysis basis is provided for the interpretation of gamma logging data; on the other hand, the application of high-speed calibration coefficients increases the upper limit of gamma preprocessing calculations, so that the formation curves obtained by the natural gamma logging instrument during high-speed logging are more stable and reliable and meet the interpretation requirements, thereby improving the logging time efficiency of the system. The use of the device of the present invention saves a lot of manpower in the process of instrument loading and calibration, improves the mechanical automation level of the calibration process, and has high instrument adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a system connection diagram, showing the connection relationship between the various functional units of the scale device.

[0034] Figure 2 This is a calibration flow chart, showing the overall operation process of the instrument gamma calibration.

[0035] Figure 3 It is a schematic diagram of the assembly structure of the scale device.

[0036] Figure 4 This is the system bench structure diagram.

[0037] Figure 5 This is the structural diagram of the calibration source box.

[0038] Figure 6 This is the structural diagram of the track system.

[0039] Figure 7 This is the structural diagram of the lifting platform.

[0040] In the attached drawings: system stand 1, calibration source box 2, track system 3, lifting mechanism 4, control system 5, acquisition system 6, calibration instrument 7, outer frame 11, roller 12; box base 21, support cage 22, calibration source 23, box cover 24; motor 31, coupling 32, pulley set 33, linear module 34, slide 35, stop block 36, motor 41, coupling 42, screw 43, fixed base 44, slider 44, cross arm 46, V-shaped fixed base 47, track connecting base 48. DETAILED DESCRIPTION

[0041] The present invention is further described in detail below in conjunction with specific embodiments, which are intended to explain the present invention rather than to limit it.

[0042] In actual logging work, the gamma logging instrument is pulled through the formation by a cable to record gamma signals at different depths. A controllable dynamic calibration device for a natural gamma detector of the present invention establishes a comparison relationship between velocity measurement and comprehensive calibration coefficient through a dynamic gamma calibration test, so as to achieve numerical balancing of the radioactive ray counting rate collected by the sensor through the same formation under different velocity measurements, and reduce the statistical fluctuations of the natural gamma curve caused by velocity measurement changes. In order to realize the calibration scheme, the present invention designs a controllable dynamic calibration device for a natural gamma detector, which calibrates the instrument gamma detector through the movement of a calibration source box controlled by a motor, and accurately simulates different velocity measurement states.

[0043] During the logging process, the instrument is dragged through the formation for surveying. In order to simulate the relative motion relationship between the instrument and the formation, the instrument and the calibration source box must move relative to each other during calibration. If the instrument is used as a moving target, the mass of the instrument body and the clamping mechanism is too large, and the required mechanism motion track is also too long. Therefore, the calibration source box is used as a moving target to reduce the load and volume of the mechanism.

[0044] A controllable dynamic calibration device for a natural gamma detector comprises a system stand 1, a calibration source box 2, a track system 3, a lifting mechanism 4, a control system 5, and a collection system 6.

[0045] The system stand 1 includes an outer frame 11 and rollers 12 ; the track system 3 is installed on the top of the outer frame 11 , and the rollers 12 are installed on the bottom of the outer frame 11 .

[0046] The calibration source box 2 includes a box base 21, a support cage 22, a calibration source 23 and a box cover 24; the box base 21 and the box cover 24 are buckled together to form a closed cylinder, and the support cage 22 is installed inside the closed cylinder. The calibration source 23 is supported on the support cage 22, and the calibration source 23 cooperates with the calibration instrument 7.

[0047] The track system 3 includes a motor 31, a coupling 32, a pulley group 33, a linear module 34, a slide 35, and a stop block 36; the front of the linear module 34 is a slide track and a pulley groove, and the motor 31 is fixed at both ends of the linear module 34. The motor 31 drives the coupling 32 to rotate in coordination with the pulley group 33, and the pulley group 33 drives the belt to move inside the pulley groove. The belt is connected to the slide 35, and the slide 35 is slidably connected to the slide track. Stop blocks 36 are installed at both ends of the linear module 34, and the stop blocks 36 are made of rubber material. A fixing groove of the calibration source box 2 is set on the slide 35, and the fixing groove cooperates with the boss of the box base 21 to increase the thrust of the calibration source box 2 during the forward and backward movement.

[0048] The lifting mechanism 5 includes a motor 41, a coupling 42, a lead screw 43, a fixed base 44, a slider 44, a cross arm 46, a V-shaped fixed base 47, and a track connection base 48;

[0049] The track connection base 48 is installed on the track system 3, and the track connection base 48 is slidably connected along the track system 3. A motor 41 is installed on the side of the track connection base 48. The output shaft of the motor 41 is connected to the lead screw 43 through the coupling 42. The lead screw 43 is connected to a slider 45. The slider 45 is connected to the bottom of the cross arm 46. The motor 41 rotates the coupling 42 to drive the lead screw 43 to make the slider 45 move forward and backward, so that the cross arm 46 moves up and down; a V-shaped fixed platform 47 is installed on the top of the cross arm 46, and the V-shaped fixed platform 47 is used to support the scale instrument 7. The control system 5 includes a controller, a power supply, and a driver; the acquisition system 6 includes a connector and a computer.

[0050] The main body of the calibration device in the present invention is designed as a rigid frame structure to ensure stability during the calibration process. In order to enable the calibration source box to slide smoothly, the source box is hoisted above the instrument to avoid being hindered by the instrument support mechanism during movement. The instrument support mechanism should be able to adjust the support height to improve the adaptability of the calibration instrument.

[0051] The main function of the calibration source box 2 in the present invention is to load radioactive materials and form a shaft-shaped calibration environment. Therefore, the structure of the calibration source box is a cylindrical cavity structure, and radioactive sources such as yellow cloth and tiles are installed inside, and a support structure is designed to ensure the stability of the radioactive material carrier during movement. The source box is designed as two openable semi-cylinders to facilitate the loading of instruments and radioactive sources, and the bottom is a connecting structure fixed to the track slide.

[0052] The calibration device in the present invention must meet the calibration requirements of instruments with different diameters, so the positional relationship between the instrument and the calibration source box must be adjustable to ensure that the center of the radiation field generated by the source box is concentric with the axis of the instrument. A motor-controlled lifting mechanism is used to achieve adjustable instrument height to ensure the best calibration effect.

[0053] The signal preprocessing of the gamma probe in the present invention requires comparing the signal relationship at different times at the same formation position, that is, when the moving distance of the source box meets the fastest logging, the state simulation of multiple acquisition points before and after is performed, and the track length is designed to meet the fastest measurement speed V MAX The effective time interval value requirements in the state. For example, the gamma data acquisition time interval t is 200 milliseconds, and the number of reference points n before and after the interval is 5. The effective moving distance L1 of the source box should meet the following requirements:

[0054] L1=VMAX*t*n=1000*0.2*10 / 3600=0.56m

[0055] Considering different types of gamma logging instrument structures, there are single-probe or dual-probe types. To meet the calibration requirements of dual-probe instruments, the moving distance of the calibration source box must span the internal interval of the dual probes. For example, if the probe measurement point interval S is 1m, the effective sliding distance L of the slide should not be less than:

[0056] L≥L1+S=1+0.56=1.56m

[0057] The track sliding distance L should be designed according to the time interval t, number of reference points n, and probe spacing S required for the actual scale.

[0058] The present invention operates the driver through the controller interface to power the motor and control the motion state. The motion mechanism of the scale device is two places, one is the slide lateral transport mechanism, and the other is the instrument lifting platform height adjustment mechanism. The two motors are controlled by the driver respectively. The slide motion mechanism is two synchronous motors that cooperate to drive the pulley to drive the slide to complete the linear module movement; the lifting platform motion mechanism is two synchronous motors that cooperate to drive the lead screw to push the support arm to lift and fall to complete the height adjustment of the mechanism.

[0059] The present invention obtains the comprehensive calibration coefficient of the gamma probe in different speed measurement states through a controllable dynamic calibration method and a calibration device. On the one hand, the calculation accuracy of the gamma detection data preprocessing process is improved, and a more scientific and reliable analysis basis is provided for the interpretation of gamma logging data; on the other hand, the application of the high-speed calibration coefficient increases the upper limit of the gamma preprocessing calculation, so that the formation curve obtained by the natural gamma logging instrument during high-speed logging is more stable and reliable and meets the interpretation requirements, thereby improving the logging time efficiency of the system. The use of the device of the present invention saves a lot of manpower in the process of instrument loading and calibration, improves the mechanical automation level of the calibration process, and has high instrument adaptability.

[0060] A controllable dynamic calibration method for a natural gamma detector includes the following steps:

[0061] Hang the calibration source box 2 on the rail system 3 and open the calibration source box 2, place the calibrated instrument 7 on the lifting mechanism 4 and close the calibration source box 2. At this time, adjust the lifting mechanism 4 to make the central tubes of the calibrated instrument 7 and the calibration source box 2 concentric.

[0062] The driving track system 3 drives the calibration source box 2 to slide and test the motion state, opens the connector of the calibrated instrument 7 for communication connection, and completes the calibration preparation work.

[0063] At the beginning of the calibration process, the control system 5 drives the track system 3 to move the calibration source box 2, and the calibration source box 2 passes through the instrument probe at different speeds set according to the calibration requirements, and the gamma sensing data is recorded in groups. The data preprocessing is completed according to the actual measurement results to obtain the calibration constant value under different speed measurement states. At the end of the calibration, the calibration source box 2 is opened and the lifting mechanism 4 is reset, the instrument communication is disconnected, the calibrated instrument 7 is removed, and the calibration source 23 in the calibration source box 2 is removed and stored in a standardized manner.

[0064] The relationship model between the calibration constant and the velocity measurement is established, with the conventional logging velocity V as the calibration simulation variable, T 源 is the gamma value of the scale box, T 测 The calibration constant K is established for the gamma measurement value of the instrument probe V , B V Functional relationship with the scale value.

[0065] T 源 =K V T 测 +B V =(a×V+b)T 测 +(c×V+d)

[0066] Where, T 源 is the gamma value of the scale box, T 测 is the gamma measurement value of the instrument probe, K V , B V is the scale constant; T 测 is the gamma measurement value of the instrument probe at each speed moment; V is the measured speed; a, b, c are all constants, and d is the floating deviation of the overall adjustment curve.

[0067] Taking the conventional logging speed range as the measurement interval, the logging speed V value is proposed to be between 400m / h and 1000m / h, with 100m / h as the interval point scale value, and the gamma measurement value T of the instrument probe at each speed moment is measured. 测 , find the scale constant K V , B V Functional relationship with the speed V. Interval between points K V , B V The change trend is obtained by curve fitting interpolation operation, and K in this speed range is established. V , BV The corresponding change curve of the measured speed V is obtained, thus obtaining the mathematical model of the relationship between the scale constant and the measured speed.

[0068] Example

[0069] A controllable dynamic calibration device for a natural gamma detector, such as Figure 1-3 As shown, it includes a system stand 1, a calibration source box 2, a track system 3, a lifting mechanism 4, a control system 5, a collection system 6, and an instrument 7.

[0070] like Figure 1 As shown, the calibration device controls the motors of the track system 3 and the lifting mechanism 4 to operate the calibration system through the driver of the control system 5. The motor of the track system 3 controls the movement of the slide 35, driving the calibration source box 2 to calibrate the instrument at different speeds. The motor of the lifting mechanism 4 drives the instrument to rise and fall, and adjusts the relative position of the instrument core and the calibration source box 2. The instrument is connected to the computer of the acquisition system 6 through a soft link to complete the data acquisition of the gamma calibration process.

[0071] like Figure 2 As shown, the operation flow of calibration is as follows: the preparation process first hangs the calibration source box 2 on the slide 35 and opens the box cover 24, loads the calibration source 23 and the support cage 22, and then places the calibrated instrument 7 on the lifting mechanism 4 and closes the box cover 24. At this time, the lifting mechanism 4 is adjusted to make the instrument 7 and the central tube of the calibration source box 2 concentric. The driving track system 3 drives the calibration source box 2 to slide and test the motion state, opens the instrument 7 connector for communication connection, and completes the calibration preparation work. Then the calibration process begins, and the control system 5 drives the slide 35 to drive the calibration source box 2, and passes through the instrument probe at different speeds set according to the calibration requirements, records the gamma sensing data in groups, and completes the data preprocessing according to the actual measurement results to obtain the calibration constant value under different speed measurement states. Finally, the calibration is completed, the box cover 24 is opened and the lifting mechanism 4 is reset, the instrument communication is disconnected and the instrument 7 is removed, and the calibration source 23 in the calibration source box 2 is removed and stored in a standardized manner.

[0072] like Figure 3 As shown, the calibration device assembly supports the track system 3 through the system stand 1, the calibration source box 2 and the lifting mechanism 4 are installed on the track system 3, and the instrument 7 is placed on the lifting mechanism 4. The control system 5 is connected to the motor drive system of the track system 3 and the lifting mechanism 4, and the acquisition system 6 is connected to the calibrated instrument 7.

[0073] like Figure 4 As shown, this example provides a mobile system stand 1, and the outer frame 11 is a welded integral bracket with two track support brackets. A roller 12 is installed at the bottom, and the roller is locked to keep the system stable during calibration. The installation of the calibration system is not limited to the mobile stand, and can also be installed on other fixed work surfaces.

[0074] like Figure 5 As shown, the calibration source box 2 is buckled into a closed cylinder by a box base 21 and a box cover 24, and the two are connected by a hinge to realize opening and closing action, which is convenient for loading the calibration instrument 7. The box base has a fixing bolt and a source box fixing boss connected to the slide 35. In order to increase the stability of the calibration source 23 in the calibration source box 2 during the calibration process, a support cage 22 is installed in the cylinder to provide support for the calibration source 23. The support cage 22 is a metal frame, and its two ends are fixed with the circular positioning grooves of the box base 21 and the box cover 24.

[0075] like Figure 6 As shown, the track system 3 is composed of a motor 31, a coupling 32, a pulley group 33, a linear module 34, a slide 35, and a stop block 36. During operation, the motor 31 is driven by the control system 4 to drive the coupling 32 to rotate in coordination with the pulley group 33. The motor can use a single motor or a double synchronous motor according to the power requirements. The front of the linear module 34 is a slide track and a pulley groove, and there is a track on each side for installing the lifting mechanism 4. The slide 35 is hung on the track of the linear module 34, and the interior is connected to the pulley group 33 through a fixed block to move synchronously with the belt. The slide 35 has a fixed groove for the calibration source box 2, which cooperates with the boss of the box base 21 to increase the thrust of the calibration source box 2 during the forward and backward movement. The stop block 36 is made of rubber and is installed on the track of the linear module 34 to constrain the moving range of the slide 35 and prevent the slide 35 from colliding with the lifting mechanism 4.

[0076] like Figure 7 As shown, there are two lifting mechanisms 4, which are composed of a motor 41, a coupling 42, a lead screw 43, a fixed base 44, a slider 45, a cross arm 46, a V-shaped fixed platform 47, and a track connection base 48. During operation, the control system 4 drives the motor 41 to drive the coupling 42, and rotates the lead screw 43 to make the slider 45 move forward and backward. The slider 45 translates in the sliding groove of the fixed base 44 to drive the cross arm 46 to fold and lift, complete the height adjustment of the V-shaped fixed platform 47, and then adjust the relative position of the instrument 7 and the calibration source box 2. The track connection base 48 is installed on the linear module 34, and the distance between the two lifting mechanisms 4 is adjusted by sliding the track on the side to adapt to instruments 7 of different lengths.

Claims

1. A controllable dynamic calibration device for a natural gamma detector, characterized in that: It comprises a system stand (1), a calibration source box (2), a track system (3), a lifting mechanism (4), a control system (5), and a collection system (6); The track system (3) is fixed on the system stand (1), and the calibration source box (2) is arranged on the track system (3) for sliding connection; lifting mechanisms (4) are installed on both sides of the calibration source box (2), and the lifting mechanisms (4) are used to support the calibration instrument (7); the control system (5) is connected to the track system (3) and the motor drive system of the lifting mechanism (4), and the acquisition system (6) is connected to the calibrated instrument (7).

2. A controllable dynamic calibration device for a natural gamma detector according to claim 1, characterized in that: The system stand (1) comprises an outer frame (11) and rollers (12); a track system (3) is installed on the top of the outer frame (11), and the rollers (12) are installed on the bottom of the outer frame (11).

3. A controllable dynamic calibration device for a natural gamma detector according to claim 1, characterized in that: The calibration source box (2) comprises a box base (21), a support cage (22), a calibration source (23) and a box cover (24); The box base (21) and the box cover (24) are buckled together to form a closed cylinder, a support cage (22) is installed inside the closed cylinder, a calibration source (23) is supported on the support cage (22), and the calibration source (23) cooperates with the calibration instrument (7).

4. The controllable dynamic calibration device of a natural gamma detector according to claim 1, characterized in that: The track system (3) comprises a motor (31), a coupling (32), a pulley group (33), a linear module (34), a slide (35), and a stop block (36); The front of the linear module (34) is a slide rail and a pulley groove. Motors (31) are fixed at both ends of the linear module (34). The motor (31) drives the coupling (32) to rotate in coordination with the pulley group (33). The pulley group (33) drives the belt to move inside the pulley groove. The belt is connected to the slide (35), and the slide (35) is slidably connected to the slide rail.

5. A controllable dynamic calibration device for a natural gamma detector according to claim 4, characterized in that: Stop blocks (36) are installed at both ends of the linear module (34), and the stop blocks (36) are made of rubber material.

6. A controllable dynamic calibration device for a natural gamma detector according to claim 4, characterized in that: The slide table (35) is provided with a fixing groove for the calibration source box (2), and the fixing groove cooperates with the boss of the box base (21) to increase the thrust of the calibration source box (2) during the forward and backward movement.

7. The controllable dynamic calibration device of a natural gamma detector according to claim 1, characterized in that: The lifting mechanism (5) comprises a motor (41), a coupling (42), a lead screw (43), a fixed base (44), a slider (44), a cross arm (46), a V-shaped fixed base (47), and a track connection base (48); The track connection base (48) is installed on the track system (3), and the track connection base (48) is slidably connected along the track system (3). A motor (41) is installed on the side of the track connection base (48). The output shaft of the motor (41) is connected to a lead screw (43) through a coupling (42). A slider (45) is connected to the lead screw (43). The slider (45) is connected to the bottom of the cross arm (46). The motor (41) rotates the coupling (42) to drive the lead screw (43) to make the slider (45) move forward and backward, so that the cross arm (46) moves up and down; a V-shaped fixed platform (47) is installed on the top of the cross arm (46), and the V-shaped fixed platform (47) is used to support the scale instrument (7).

8. A controllable dynamic calibration method for a natural gamma detector, characterized in that: A controllable dynamic calibration device for a natural gamma detector according to any one of claims 1 to 7, comprising: The calibration source box (2) is hoisted on the track system (3) and the calibration source box (2) is opened. The calibrated instrument (7) is placed on the lifting mechanism (4) and the calibration source box (2) is closed. At this time, the lifting mechanism (4) is adjusted so that the central tubes of the calibrated instrument (7) and the calibration source box (2) are concentric. The driving track system (3) drives the calibration source box (2) to slide and test the motion state, opens the connector of the calibrated instrument (7) for communication connection, and completes the calibration preparation work; The calibration process begins, the control system (5) drives the track system (3) to drive the calibration source box (2) to move, and the calibration source box (2) passes through the instrument probe at different speeds set according to the calibration requirements, and the gamma sensing data is recorded in groups. The data preprocessing is completed according to the actual measurement results to obtain the calibration constant values ​​under different speed measurement states; when the calibration is completed, the calibration source box (2) is opened and the lifting mechanism (4) is reset, the instrument communication is disconnected, and the calibrated instrument (7) is removed, and the calibration source (23) in the calibration source box (2) is removed and stored in a standardized manner.

9. A controllable dynamic calibration method for a natural gamma detector according to claim 8, characterized in that: The model formula of the relationship between the scale constant and the speed measurement is: T 源 =K V T 测 +B V =(a×V+b)T 测 +(c×V+d) Where, T 源 is the gamma value of the scale box, T 测 is the gamma measurement value of the instrument probe, K V , B V is the scale constant; T 测 is the gamma measurement value of the instrument probe at each speed moment; V is the measured speed; a, b, c are all constants, and d is the floating deviation of the overall adjustment curve.

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