A follow-up quantitative sampling device for rock cuttings and its control method

Abstract

This invention relates to the field of cuttings logging operations in oil and gas field exploration and development, specifically to a follow-up quantitative cuttings sampling device and control method. The sampling device includes a base, a flushing mechanism, a sampling mechanism, and a drive mechanism. The base includes a base slide rail and a base frame. The flushing mechanism includes a water distributor and a receiving hopper flushing pipe. The sampling mechanism is fixedly connected to the base and includes a sampler mounting bracket, a receiving hopper, and a quantitative cuttings sampler. The drive mechanism is fixedly connected to the base and includes a transmission box and a motor. The follow-up quantitative cuttings sampling device disclosed in this invention can operate fully automatically and continuously, realizing the automation and intelligence of cuttings collection and sampling work, significantly improving operational safety and efficiency.

Description

Technical Field

[0001] This invention relates to the field of cuttings logging technology in the exploration and development of oil and gas fields, specifically to a follow-up quantitative cuttings sampling device and control method. Background Technology

[0002] Cuttings logging is a key technology that analyzes cuttings carried from the bottom of the well to the surface by drilling mud to identify stratigraphic sequences, determine lithology, and preliminarily assess the oil, gas, and water content of the formation. This method has advantages such as low cost, ease of operation, real-time performance, and a complete data system.

[0003] In traditional operations, cuttings collection relies on manual labor: geologists manually collect cuttings from below a vibrating mud screen, clean them, and then analyze them. However, with the extended drilling cycle (often lasting tens of days to months) and the need for high-frequency sampling under complex geological conditions (such as sampling every few meters, with the shortest interval being only 1 to 2 minutes), manual methods have revealed many problems: high labor intensity, harsh working environment, low sampling efficiency, and susceptibility to sample confusion due to operational errors, which in turn affects the accuracy of geological interpretation and the effectiveness of exploration and development.

[0004] In the prior art, patent document CN115653523A discloses a rock cuttings quantitative collection device and a rock cuttings collection and analysis system. The quantitative collection device includes a frame, a drive motor, a quantitative shell, and a receiving component. The drive motor and the quantitative shell are both mounted on the frame. The receiving component is connected to the output shaft of the drive motor and has multiple collection troughs arranged continuously in the circumferential direction of the output shaft. The quantitative shell is provided with a receiving cavity and a receiving port and a discharge port, both of which are connected to the receiving cavity. The receiving component is located inside the receiving cavity. When the drive motor drives the receiving component to rotate relative to the quantitative shell, the opening of the collection trough that moves to the receiving port is connected to the receiving port, and the opening of the collection trough that leaves the receiving port is closed by the quantitative shell. The discharge port is used to discharge the rock cuttings in the collection trough whose opening is closed by the quantitative shell. For example, patent document CN203241269U discloses an automatic device for collecting and cleaning geological logging cuttings. This device consists of a sand collecting plate, a sand extraction port, a sand extractor, a sand extractor motor, a return water pipe, a water inlet pipe, a sand washing machine cover, a duckbill buckle, an elbow, a sand storage cylinder, a sand extraction disc, a remote control terminal, a controller, a sand washing machine cylinder, a turntable motor, a turntable, a support, a filter screen, a submersible pump, a connecting pipe, a water injection valve, a wastewater cylinder, a water tank, and a drain valve. While the technical solutions disclosed in the aforementioned two patent documents have solved the problem of quantitative sampling of cuttings to some extent, the sampling structures and methods described still have significant limitations. They cannot achieve continuous sampling of cuttings, which can easily lead to missed sampling and incomplete geological data.

[0005] Therefore, overcoming the aforementioned technical problems and defects has become a key issue that needs to be addressed. Summary of the Invention

[0006] This invention provides a follow-up rock cuttings quantitative sampling device and control method, aiming to realize the automation, continuity and quantification of rock cuttings sampling, effectively improve sampling efficiency and data reliability, significantly reduce manual labor intensity, improve working conditions, ensure the integrity and accuracy of geological data, and provide more solid data support for geological analysis.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a follow-up rock cuttings quantitative sampling device, comprising a base, a flushing mechanism, a sampling mechanism, and a driving mechanism;

[0008] The base includes a base slide rail and a base frame. The base slide rail consists of multiple rails. The base frame slides in slidable engagement with the multiple base slide rails and can be fixed in a set position on the base slide rail using fasteners.

[0009] The rinsing mechanism includes a water distributor and a hopper rinsing pipe. The water distributor's inlet is connected to an external water supply pipe, and its outlet is connected to a sampling mechanism. The water distributor is equipped with a branch pipe and an inlet valve. The inlet valve is located between the branch pipe and the sampling mechanism. The end of the branch pipe away from the water distributor is connected to the hopper rinsing pipe via a hopper rinsing inlet hose. The other end of the hopper rinsing pipe is connected to a hopper rinsing return hose. The branch pipe is equipped with a hopper rinsing inlet valve.

[0010] The sampling mechanism is fixedly connected to the base and includes a sampler mounting bracket, a receiving hopper, and a rock cutting quantitative sampler. The sampler mounting bracket is fixedly assembled on the upper end of the base frame. The lower end of the receiving hopper is movably connected to the upper end of the rock cutting quantitative sampler. The receiving hopper flushing pipe is arranged on the upper end of the receiving hopper and has multiple flushing holes.

[0011] The drive mechanism is fixedly connected to the base and includes a transmission box and a motor. The two ends of the rock cutting quantitative sampler are fixedly connected to the sampler mounting bracket and the transmission box, respectively. The motor output shaft is connected to the main transmission shaft in the transmission box. The main transmission shaft in the transmission box is driven by the driven shaft. The driven shaft extends into the rock cutting quantitative sampler.

[0012] Furthermore, the rock cuttings quantitative sampler includes a rock cuttings quantitative sampling shell and a rock cuttings quantitative sampling trough. The rock cuttings quantitative sampling shell includes a rock cuttings quantitative sampler inlet pipe, a rock cuttings quantitative sampler housing, a rock cuttings quantitative sampler feed inlet, a receiving hopper flushing return water pipe, and a rock cuttings quantitative sampler discharge pipe. One end of the rock cuttings quantitative sampler inlet pipe is connected to the outlet of the water distributor. The rock cuttings quantitative sampler inlet pipe and the receiving hopper flushing return water pipe are symmetrically arranged on both sides of the rock cuttings quantitative sampler discharge pipe. The rock cuttings quantitative sampler feed inlet is opened on the rock cuttings quantitative sampler housing and is correspondingly arranged at the lower end of the receiving hopper. The rock cuttings quantitative sampler discharge pipe is located at the lower end of the rock cuttings quantitative sampler housing, and a receiving hopper flushing return water rigid pipe is provided at the lower end of the rock cuttings quantitative sampler discharge pipe.

[0013] Furthermore, the rock cuttings quantitative sampling rotating trough includes a rock cuttings quantitative sampling trough and a rock cuttings quantitative sampling trough rotating shaft. One end of the rock cuttings quantitative sampling trough rotating shaft is connected to a drive shaft, and the rock cuttings quantitative sampling trough is located at the other end of the rock cuttings quantitative sampling trough rotating shaft.

[0014] Furthermore, the rock cuttings quantitative sampling troughs are multiple circumferentially arranged.

[0015] A follow-up quantitative sampling control method for rock cuttings, the method comprising:

[0016] Obtain the current late well depth and remaining sampling time from the logging instrument;

[0017] Determine if there are sudden changes in drilling speed or mud inlet flow rate;

[0018] When no cuttings are present, the control motor collects cuttings at a fixed output frequency during the current cuttings collection cycle; the fixed output frequency is determined based on the current late well depth and the remaining sampling time.

[0019] When present, within the current cuttings collection cycle, the output frequency is dynamically updated based on the current late arrival depth, remaining sampling time, and number of output pulses, and the motor is controlled to collect cuttings using the dynamically updated output frequency.

[0020] Furthermore, the dynamic updating of the output frequency based on the current late arrival well depth, remaining sampling time, and number of output pulses includes:

[0021] Determine whether the current late well depth is not less than the initial late well depth;

[0022] When the current late well depth is not less than the initial late well depth, determine whether the distance between the current late well depth and the initial late well depth is greater than the preset well depth interval D; the initial late well depth is the late well depth when cuttings collection begins;

[0023] When the value is not greater than D, the number of output pulses and the remaining sampling time are collected, and the output frequency is dynamically updated based on the number of output pulses and the remaining sampling time.

[0024] When the value is greater than D, the current late well depth is used as the initial late well depth, the initial late well depth value is updated, and the current late well depth is re-evaluated to see if it is not less than the initial late well depth.

[0025] Furthermore, the formula for calculating the fixed output frequency is:

[0026] F = DxN2xIxN3 / T1;

[0027] Where F represents the fixed motor output frequency, D represents the well depth interval, I represents the reduction ratio, N2 represents the number of rotations required for the acquisition device to rotate when the late well depth increases by 1 meter to meet the quantitative sampling requirements, N3 represents the number of pulses required for the stepper motor to rotate one revolution, and T1 represents the remaining sampling time.

[0028] The formula for calculating the dynamically updated output frequency is:

[0029] F = ( DxN2xIxN3–N1 ) / T1 ;

[0030] Where F represents the dynamically updated motor output frequency, D represents the well depth interval, I represents the reduction ratio, N1 represents the number of output pulses, N2 represents the number of rotations required for the acquisition device to complete when the late well depth increases by 1 meter to meet the quantitative sampling requirements, N3 represents the number of pulses required for the stepper motor to complete one rotation, and T1 represents the remaining sampling time.

[0031] Compared with the prior art, the beneficial effects of the present invention are:

[0032] 1. The present invention discloses a follow-up quantitative rock cuttings sampling device, which can operate fully automatically and continuously, completely freeing operators from direct contact with vibrating screens and high-frequency repetitive physical labor. It not only greatly reduces labor intensity and personal safety risks, but also avoids missed or incorrect sampling due to human fatigue or negligence. It fundamentally improves the standardization and efficiency of rock cuttings collection and sampling, realizes the automation and intelligence of rock cuttings collection and sampling work, and significantly improves operational safety and efficiency.

[0033] 2. This invention discloses a follow-up quantitative cuttings sampling method, which differs from traditional manual intermittent sampling or some simple devices that can only obtain scattered cuttings from all well depths. This device can continuously collect cuttings from all well depths at all times and proportionally. The resulting samples fully represent the formation information of the entire drilling profile, effectively avoiding the omission of key formations. This provides extremely reliable and high-quality data support for accurate geological evaluation and oil and gas reservoir discovery, thus ensuring the continuity and representativeness of the samples and providing a high-quality data foundation for geological analysis. Attached Figure Description

[0034] Figure 1 This is a diagram showing the usage status of the follow-up rock cuttings quantitative sampling device paired with a mud vibrating screen in Example 1;

[0035] Figure 2 This is a schematic diagram of the follow-up rock cuttings quantitative sampling device in Example 1;

[0036] Figure 3 This is a schematic diagram of the base structure of Example 1;

[0037] Figure 4 This is a schematic diagram of the rock cuttings quantitative sampler in Example 1;

[0038] Figure 5 This is a schematic diagram of the structure of the shell for quantitative rock cuttings sampling in Example 1;

[0039] Figure 6 This is a schematic diagram of the structure of the rock cuttings quantitative sampling transfer tank in Example 1;

[0040] Figure 7 This is a flowchart of the follow-up quantitative sampling control method for rock cuttings in Example 2.

[0041] Figure Labels

[0042] 1: Follow-up rock cuttings quantitative sampling device; 2: Mud slurry vibrating screen;

[0043] 1-1: Base, 1-1-1: Base slide rail, 1-1-2: Base bracket;

[0044] 1-2: Water distributor; 1-3: Water inlet valve; 1-4: Water inlet valve for flushing hopper; 1-5: Water inlet hose for flushing hopper; 1-9: Water inlet pipe for flushing hopper; 1-10: Water return hose for flushing hopper.

[0045] 1-6: Sampler mounting bracket; 1-7: Receiving hopper; 1-8: Rock cuttings quantitative sampler; 1-8-1: Rock cuttings quantitative sampler housing; 1-8-2: Rock cuttings quantitative sampler rotating trough; 1-8-1-1: Rock cuttings quantitative sampler water inlet pipe; 1-8-1-2: Rock cuttings quantitative sampler housing; 1-8-1-3: Rock cuttings quantitative sampler feed inlet; 1-8-1-4: Receiving hopper flushing return water pipe; 1-8-1-5: Rock cuttings quantitative sampler discharge pipe; 1-13: Receiving hopper flushing return water rigid pipe; 1-8-2-1: Rock cuttings quantitative sampler trough; 1-8-2-2: Rock cuttings quantitative sampler trough rotating shaft;

[0046] 1-11: Transmission box; 1-12: Motor. Detailed Implementation

[0047] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] Example 1, please refer to Figures 1 to 3 The present invention provides a follow-up rock cuttings quantitative sampling device 1, which is installed below the discharge port of the mud vibrating screen 2. After the rock cuttings are separated by vibration of the mud vibrating screen 2, they fall from the outlet of the mud vibrating screen 2. The follow-up rock cuttings quantitative sampling device 1 is located below the discharge port of the mud vibrating screen 2 and continuously collects the rock cuttings.

[0049] Specifically, the follow-up rock cuttings quantitative sampling device 1 includes a base 1-1, a flushing mechanism, a sampling mechanism, and a driving mechanism.

[0050] The base 1-1 includes a base slide rail 1-1-1 and a base frame 1-1-2. In this embodiment, the base slide rails 1-1-1 are two parallel rails. The two ends of the base frame 1-1-2 are respectively slidably engaged with the two base slide rails 1-1-1. The relative position of the base frame 1-1-2 on the base slide rails 1-1-1 can be adjusted using fasteners (such as screws). The base adopts a sliding design, which allows the operator to precisely adjust the relative distance between the end of the sampling device and the rock cuttings outlet of the mud vibrating screen. When the optimal rock cuttings collection position is adjusted, the base frame 1-1-2 can be firmly fixed on the base slide rails 1-1-1 by tightening the locking screws to prevent the sampling device from shifting during operation.

[0051] The rinsing mechanism includes a water distributor 1-2 and a hopper rinsing pipe 1-9. The inlet of the water distributor 1-2 is connected to an external water supply pipe, and the outlet is connected to the sampling mechanism. A branch pipe and an inlet valve 1-3 are installed on the water distributor 1-2. The inlet valve 1-3 is located between the branch pipe and the sampling mechanism. The inlet valve 1-3 is used to control the flow and flow rate of the water supplied to the sampling mechanism. The end of the branch pipe away from the water distributor 1-2 is connected to the hopper rinsing pipe 1-9 through a hopper rinsing inlet hose 1-5. The other end of the hopper rinsing pipe 1-9 is connected to a hopper rinsing return hose 1-10. A hopper rinsing inlet valve 1-4 is installed on the branch pipe. The hopper rinsing inlet valve 1-4 is used to control the flow and flow rate of the water in the hopper rinsing pipe 1-9.

[0052] The sampling mechanism is fixedly connected to the base 1-1, including the sampler mounting bracket 1-6, the receiving hopper 1-7 and the rock cuttings quantitative sampler 1-8. The sampler mounting bracket 1-6 is fixedly assembled on the upper end of the base frame 1-1-2.

[0053] In this embodiment, the receiving hopper 1-7 adopts a grooved plate that is wider at the top and narrower at the bottom. This is to ensure that sufficient rock cuttings can still be collected when the amount of rock cuttings discharged from the discharge port of the mud vibrating screen 2 is small or uneven. The lower end of the receiving hopper 1-7 is movably connected to the upper end of the rock cuttings quantitative sampler 1-8. The flushing pipe 1-9 of the receiving hopper is arranged at the upper end of the receiving hopper 1-7 to adjust the angle between the receiving hopper 1-7 and the discharge port of the mud vibrating screen 2, so that the rock cuttings collected by the receiving hopper 1-7 can fall smoothly into the rock cuttings quantitative sampler 1-8, preventing the rock cuttings from accumulating on the receiving hopper 1-7. The flushing pipe 1-9 of the receiving hopper is provided with multiple flushing holes, and the water sprayed from the flushing holes flushes the rock cuttings in the receiving hopper 1-7. The flushing inlet hose 1-5 and the flushing return hose 1-10 of the receiving hopper are designed as hoses to adapt to changes in the angle and position of the receiving hopper 1-7, and the flushing pipe 1-9 follows the receiving hopper 1-7 to make adaptive adjustments.

[0054] In this embodiment, the rock cuttings quantitative sampler 1-8 includes a rock cuttings quantitative sampling shell 1-8-1 and a rock cuttings quantitative sampling trough 1-8-2. The rock cuttings quantitative sampling shell 1-8-1 includes a rock cuttings quantitative sampler inlet pipe 1-8-1-1, a rock cuttings quantitative sampler housing 1-8-1-2, a rock cuttings quantitative sampler feed inlet 1-8-1-3, a receiving hopper flushing return water pipe 1-8-1-4, and a rock cuttings quantitative sampler discharge pipe 1-8-1-5. One end of the rock cuttings quantitative sampler inlet pipe 1-8-1-1 is connected to the outlet of the water distributor 1-2. The sampler inlet pipe 1-8-1-1 and the hopper flushing return pipe 1-8-1-4 are symmetrically arranged on both sides of the rock cuttings quantitative sampler outlet pipe 1-8-1-5. The rock cuttings quantitative sampler inlet 1-8-1-3 is opened on the rock cuttings quantitative sampler shell 1-8-1-2 and is located at the lower end of the hopper 1-7. The rock cuttings quantitative sampler outlet pipe 1-8-1-5 is located at the lower end of the rock cuttings quantitative sampler shell 1-8-1-2. The hopper flushing return pipe 1-13 is installed at the lower end of the rock cuttings quantitative sampler outlet pipe 1-8-1-5.

[0055] In this embodiment, the rock cuttings quantitative sampling rotating trough 1-8-2 includes a rock cuttings quantitative sampling trough 1-8-2-1 and a rock cuttings quantitative sampling trough rotating shaft 1-8-2-2. The rock cuttings quantitative sampling trough 1-8-2-1 is located at the other end of the rock cuttings quantitative sampling trough rotating shaft 1-8-2-2, and there are multiple rock cuttings quantitative sampling troughs 1-8-2-1 arranged circumferentially.

[0056] The drive mechanism is fixedly connected to the base 1-1 and includes a transmission box 1-11 and a motor 1-12. The two ends of the rock cutting quantitative sampler 1-8 are fixedly connected to the sampler mounting bracket 1-6 and the transmission box 1-11, respectively. The output shaft of the motor 1-12 is connected to the main drive shaft in the transmission box 1-11. The main drive shaft in the transmission box 1-11 is engaged with the driven shaft. The driven shaft extends into the rock cutting quantitative sampler 1-8 and is connected to one end of the rock cutting quantitative sampling groove rotating shaft 1-8-2-2.

[0057] In this embodiment, motors 1-12 are stepper motors or servo motors. Through the transmission cooperation between the main drive shaft and the driven shaft, the rotation angle of the rock cuttings quantitative sampling turntable 1-8-2 can be precisely controlled.

[0058] In the above specific embodiments, the method of using the follow-up rock cuttings quantitative sampling device 1 in conjunction with the mud vibrating screen 2 is as follows:

[0059] Place the follow-up rock cuttings quantitative sampling device 1 below the mud vibrating screen 2 (adjust the position of the base frame 1-1-2 as needed), adjust the receiving angle of the receiving hopper 1-7 so that the receiving hopper 1-7 can receive the rock cuttings falling from the discharge port of the mud vibrating screen 2. The top of the receiving hopper 1-7 rests on the mud vibrating screen 2. The design of the receiving hopper 1-7 being wider at the top and narrower at the bottom is to ensure that sufficient rock cuttings can still be collected when the amount of rock cuttings discharged from the discharge port of the mud vibrating screen 2 is small or uneven. The adjustable angle tilt design of the receiving hopper is to allow the rock cuttings to fall smoothly along the receiving hopper 1-7 into the inlet 1-8-1-3 of the rock cuttings quantitative sampler under the action of gravity.

[0060] The external water supply line begins to supply water to the water distributor 1-2. The water distributor 1-2 divides the water line into two lines, supplying water to the receiving hopper flushing pipe 1-9 and the rock cuttings quantitative sampler inlet pipe 1-8-1-1 respectively. During the collection of rock cuttings, the receiving hopper flushing pipe 1-9 continuously flushes the receiving hopper 1-7 to prevent rock cuttings from accumulating on the receiving hopper 1-7. Unused water in the receiving hopper flushing pipe 1-9 is led out along the receiving hopper flushing return water hose 1-10. The flushed water is led out through the receiving hopper flushing return water hard pipe 1-13. The two outflowing water lines are collected together with the hopper flushing return water pipe 1-8-1-4, which prevents particulate impurities in the circulating water from clogging the pipes.

[0061] The motor control unit drives motor 1-12 to rotate according to the control program. Motor 1-12 drives the rock cuttings quantitative sampling trough 1-8-2 to rotate continuously through the transmission components in the transmission box 1-11. The upper sampling trough of the rock cuttings quantitative sampling trough 1-8-2-1 is exposed at the inlet 1-8-1-3 of the rock cuttings quantitative sampler. Rock cuttings fall into the rock cuttings quantitative sampling trough 1-8-2-1. Because the amount of rock cuttings falling is sufficient, the upper exposed trough of the rock cuttings quantitative sampling trough 1-8-2-1 is always kept full of rock cuttings. At the same time, the rock cuttings quantitative sampling trough 1-8-2-1 is continuously rotating, and empty sampling troughs are constantly being filled with rock cuttings. The small trough filled with rock cuttings rotates to the closed part of the rock cuttings quantitative sampler housing 1-8-1-2, and the small trough filled with rock cuttings and the closed part of the rock cuttings quantitative sampler housing 1-8-1-2 cooperate. A space with a fixed volume is formed, which can hold a specific volume of rock cuttings. When the small trough on the rock cuttings quantitative sampling trough 1-8-2, filled with rock cuttings, rotates to the outlet pipe 1-8-1-5 of the rock cuttings quantitative sampler, the rock cuttings in the small trough on the rock cuttings quantitative sampling trough 1-8-2 fall into the outlet pipe 1-8-1-5 of the rock cuttings quantitative sampler under the influence of gravity and water flow. At this time, water continuously enters the outlet pipe 1-8-1-5 of the rock cuttings quantitative sampler from the inlet pipe 1-8-1-1 of the rock cuttings quantitative sampler and the return water pipe 1-8-1-4 of the receiving hopper. The water flow carries the rock cuttings from the outlet pipe 1-8-1-5 of the rock cuttings quantitative sampler to the rock cuttings washing machine or other devices for the next step of the process. Thus, the rock cuttings in the small trough of the rock cuttings quantitative sampling trough 1-8-2-1 are successfully collected. Under the control of relevant algorithms, the motor control unit drives the rock cutting quantitative sampling tank 1-8-2-1 to rotate, continuously collecting a quantitative amount of rock cuttings.

[0062] Example 2 discloses a follow-up quantitative sampling control method for rock cuttings, the method including:

[0063] Obtain the current late well depth and remaining sampling time from the logging instrument;

[0064] Determine if there are sudden changes in drilling speed or mud inlet flow rate;

[0065] When no cuttings are present, the control motor collects cuttings at a fixed output frequency during the current cuttings collection cycle; the fixed output frequency is determined based on the current late well depth and the remaining sampling time.

[0066] When present, within the current cuttings collection cycle, the output frequency is dynamically updated based on the current late arrival depth, remaining sampling time, and number of output pulses, and the motor is controlled to collect cuttings using the dynamically updated output frequency.

[0067] Specifically, based on the current late arrival well depth, remaining sampling time, and number of output pulses, the output frequency is dynamically updated, including:

[0068] Determine whether the current late well depth is not less than the initial late well depth;

[0069] When the current late well depth is not less than the initial late well depth, determine whether the distance between the current late well depth and the initial late well depth is greater than the preset well depth interval D; the initial late well depth is the late well depth when cuttings collection begins;

[0070] When the value is not greater than D, the number of output pulses and the remaining sampling time are collected, and the output frequency is dynamically updated based on the number of output pulses and the remaining sampling time.

[0071] When the value is greater than D, the current late well depth is used as the initial late well depth, the initial late well depth value is updated, and the current late well depth is re-evaluated to see if it is not less than the initial late well depth.

[0072] Specifically, the formula for calculating the fixed output frequency is as follows:

[0073] F = DxN2xIxN3 / T1;

[0074] Where F represents the fixed motor output frequency, D represents the well depth interval, I represents the reduction ratio, N2 represents the number of rotations required for the acquisition device to rotate when the late well depth increases by 1 meter to meet the quantitative sampling requirements, N3 represents the number of pulses required for the stepper motor to rotate one revolution, and T1 represents the remaining sampling time.

[0075] The formula for calculating the dynamically updated output frequency is:

[0076] F = ( DxN2xIxN3–N1 ) / T1 ;

[0077] Where F represents the dynamically updated motor output frequency, D represents the well depth interval, I represents the reduction ratio, N1 represents the number of output pulses, N2 represents the number of rotations required for the acquisition device to complete when the late well depth increases by 1 meter to meet the quantitative sampling requirements, N3 represents the number of pulses required for the stepper motor to complete one rotation, and T1 represents the remaining sampling time.

[0078] The motor control unit of the cuttings collection device exchanges information with the logging instrument. From the logging network system, parameters changing every second can be read using the WITS protocol: the current late arrival depth and the remaining sampling time. Through the above control process, the rotation speed and number of revolutions of the sampling motor can be controlled in real time, thereby achieving the effect of real-time quantitative collection of cuttings.

[0079]

[0080] In actual drilling, the remaining sampling time T1 is affected by changes in drilling speed and mud inlet flow rate. However, under normal circumstances, the drilling speed of the previous meter and the average drilling speed of the next meter do not change much. The mud inlet flow rate only changes when the pump speed and the number of pumps are changed. In order to simplify the control process, the output frequency of the previous cuttings collection can be used to control the output frequency of the next collection. During the well depth interval, the control frequency of cuttings collection is constant.

[0081] To precisely control the changes in motor frequency and make cuttings collection more accurate, this embodiment introduces two parameters: the number of output pulses and the detection calculation cycle. When drilling speed and mud inlet flow rate change rapidly, the output frequency can also change instantly, greatly shortening the delay time and making cuttings collection more accurate.

[0082] The control method disclosed in this embodiment, when used with the device, can continuously collect cuttings from all well depths at all times and proportionally. The resulting samples fully represent the formation information of the entire drilling profile, effectively avoiding the omission of key formations and providing extremely reliable and high-quality data support for accurate geological evaluation and oil and gas reservoir discovery.

[0083] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A servoed cuttings quantitative sampling device, characterized in that: The base, the flushing mechanism, the sampling mechanism and the driving mechanism are included. The base includes base slides and a base frame, the base slides are multiple, and the base frame is in sliding fit with the multiple base slides and can be fixed at a set position of the base slides by using fasteners. The flushing mechanism includes a water distributor and a hopper flushing pipe, the water inlet of the water distributor is connected with an external water supply pipe, the water outlet is connected with the sampling mechanism, branch pipes and an inlet valve are arranged on the water distributor, the inlet valve is located between the branch pipes and the sampling mechanism, one end of the branch pipes away from the water distributor is connected with the hopper flushing pipe through a hopper flushing water inlet hose, the other end of the hopper flushing pipe is connected with a hopper flushing return water hose, and the branch pipes away from the water distributor are provided with a hopper flushing inlet valve. The sampling mechanism is fixedly connected to the base and includes a sampler mounting bracket, a hopper and a rock debris quantitative sampler, the sampler mounting bracket is fixedly assembled to the upper end of the base frame, the lower end of the hopper is movably connected to the upper end of the rock debris quantitative sampler, the hopper flushing pipe is arranged at the upper end of the hopper, and a plurality of flushing holes are arranged on the hopper flushing pipe. The driving mechanism is fixedly connected to the base and includes a transmission box and a motor, the rock debris quantitative sampler is fixedly connected to the sampler mounting bracket and the transmission box at two ends respectively, the output shaft of the motor is in transmission connection with a main transmission shaft in the transmission box, the main transmission shaft in the transmission box is in transmission fit with a slave transmission shaft, and the slave transmission shaft extends into the rock debris quantitative sampler. The rock debris quantitative sampler includes a rock debris quantitative sampling shell and a rock debris quantitative sampling rotary groove, the rock debris quantitative sampling shell includes a rock debris quantitative sampler water inlet pipe, a rock debris quantitative sampler housing, a rock debris quantitative sampler feed inlet, a rock debris quantitative sampler flushing return water pipe and a rock debris quantitative sampler discharge pipe, one end of the rock debris quantitative sampler water inlet pipe is connected with the water outlet of the water distributor, the rock debris quantitative sampler water inlet pipe and the rock debris quantitative sampler flushing return water pipe are symmetrically arranged at two sides of the rock debris quantitative sampler discharge pipe, the rock debris quantitative sampler feed inlet is arranged on the rock debris quantitative sampler housing and is correspondingly arranged at the lower end position of the hopper, the rock debris quantitative sampler discharge pipe is located at the lower end of the rock debris quantitative sampler housing, and the lower end of the rock debris quantitative sampler discharge pipe is provided with a hopper flushing return water hard pipe.

2. The following-up rock debris quantitative sampling device according to claim 1, characterized in that: The rock debris quantitative sampling rotary groove includes a rock debris quantitative sampling groove and a rock debris quantitative sampling groove rotary shaft, one end of the rock debris quantitative sampling groove rotary shaft is connected with the slave transmission shaft, and the rock debris quantitative sampling groove is arranged at the other end of the rock debris quantitative sampling groove rotary shaft.

3. The following device according to claim 2 is characterized in that: The rock debris quantitative sampling groove is multiple and arranged in a circumferential direction.

4. The method for controlling the following rock debris quantitative sampling device according to any one of claims 1 to 3, characterized in that, The method includes: obtaining a current late-in-hole depth and a sampling remaining time from a mud logging instrument; determining whether there is a drilling speed mutation or a mud inlet flow mutation; when there is not, controlling the motor to collect rock debris with a fixed output frequency in a current rock debris collection period, the fixed output frequency being determined based on the current late-in-hole depth and the sampling remaining time; when there is, dynamically updating an output frequency based on the current late-in-hole depth, the sampling remaining time and a number of output pulses, and controlling the motor to collect rock debris with the dynamically updated output frequency in the current rock debris collection period.

5. The method of claim 4, wherein, The output frequency is dynamically updated based on the current late hole depth, the sampling remaining time and the number of output pulses, and the method comprises the following steps: determining whether the current late hole depth is not less than the initial late hole depth; when the current late hole depth is not less than the initial late hole depth, determining whether the distance between the current late hole depth and the initial late hole depth is greater than a preset hole depth interval D; the initial late hole depth is the late hole depth when the rock debris starts to be collected; when the distance is not greater than D, collecting the number of output pulses and the sampling remaining time, and dynamically updating the output frequency based on the number of output pulses and the sampling remaining time; when the distance is greater than D, taking the current late hole depth as the initial late hole depth, updating the initial late hole depth value, and re-determining whether the current late hole depth is not less than the initial late hole depth.

6. The method of claim 4, wherein, The fixed output frequency calculation formula is: F =DxN2xIxN3 / T1; wherein, F represents the fixed motor output frequency, D represents the hole depth interval, I represents the reduction ratio, N2 represents the number of rotations required by the collection device when the late hole depth increases by 1 meter under the requirement of quantitative sampling, N3 represents the number of pulses required by the step motor to rotate one circle, and T1 represents the sampling remaining time; The dynamic updating output frequency calculation formula is: F = ( DxN2xIxN3–N1 ) / T1; wherein, F represents the dynamically updated motor output frequency, D represents the hole depth interval, I represents the reduction ratio, N1 represents the number of output pulses, N2 represents the number of rotations required by the collection device when the late hole depth increases by 1 meter under the requirement of quantitative sampling, N3 represents the number of pulses required by the step motor to rotate one circle, and T1 represents the sampling remaining time.

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