A flexible tightening system and detection and control method for drill pipe thread connection

Abstract

The present invention discloses a flexible tightening system and a detection and control method for drill pipe thread connection. The system is sequentially provided with a numerical control spiral milling machine, a fixed clamping device, a flexible screwing device and a feeding device along the coaxial direction. The drill pipe to be processed is clamped and positioned by the numerical control spiral milling machine and the fixed clamping device. The drill pipe to be screwed is conveyed to the flexible screwing device by the feeding device, and is coaxially docked with the drill pipe to be processed through a guiding device. The flexible screwing device screws the drill pipe to be processed and the drill pipe to be screwed. The thread tightening detection device detects whether the drill pipe to be processed and the drill pipe to be screwed are tightened. The flexible screwing floating device finely adjusts the position of the flexible screwing device. The ultrasonic vibration device realizes the swing of the drill pipe to be screwed in the direction with the largest displacement deviation through resonance. The present invention realizes the automation of the thread tightening process of two drill pipes during the milling spiral processing of the drill pipe, and can realize the on-line detection and control of tightening.

Description

Technical Field

[0001] The present invention relates to the production and processing of drill pipes. In some production processes, the threads of the drill pipes need to be reliably connected together to ensure that the threads between the drill pipes are tightened in place before proceeding with the production and processing. Specifically, it is a flexible tightening system and detection control method for drill pipe thread connections. Background Art

[0002] When producing and processing drill pipes, in some production processes, the threads of the drill pipes need to be connected together first, and it is necessary to ensure that the threads between the drill pipes are tightened in place, and then the production and processing are carried out (for example: in the process of milling the helix of the drill pipe, first tighten the threads of two drill pipes together, and then carry out machining). At present, the tightening of drill pipe threads mainly relies on manual operation. There are a small number of specially developed drill pipe thread screwing devices that have defects such as difficult buttoning, incomplete thread tightening, and inability to detect thread tightening in real time online, resulting in thread tightening failure. This is mainly because the central axes of the two drill pipes are not concentric, and there are machining errors in the male and female threads of each drill pipe, resulting in difficult buttoning of the drill pipe threads. At the same time, it is difficult to ensure whether the threads are tightened in place; there are also centimeter-level errors in the length of each drill pipe, and the errors will accumulate after screwing multiple drill pipes, increasing the difficulty of thread tightening detection. During the milling process of the milling machine, the drill pipe is constantly subjected to periodic milling vibrations, and the tightened drill pipes to be processed will also become loose due to the vibrations, and it is impossible to ensure that the tightened drill pipes are always in a tightened state.

[0003] When the buttoning of the drill pipes fails, the two drill pipes cannot perform the thread screwing action, and the huge impact force is also likely to cause damage to the equipment and products. When the drill pipes are not tightened, during the milling process of the CNC spiral milling machine, the spiral forward trajectory of the drill pipe is prone to distortion, and there will be pauses and lags. On the one hand, it causes the processed drill pipes to be scrapped, and on the other hand, it causes the blades of the CNC spiral milling machine to break, and the tool holders and milling cutter heads are damaged, bringing huge losses to the production. The stoppage of the automated production workstation may trigger serious factory accidents. Therefore, the present invention mainly designs an automatic buttoning flexible tightening device for drill pipe threads and an online detection control method for thread tightening. Summary of the Invention

[0004] The present invention mainly aims at the defects of the automatic thread screwing equipment for drill pipes during production and processing, such as difficult buttoning, incomplete thread tightening, and inability to detect the tightening status online. It provides a flexible tightening system and detection control method for drill pipe thread connections, which has an automatic buttoning device for drill pipe threads, a rapid flexible tightening of the threads, and an online detection of the drill pipe thread tightening, and a detection method that can detect and judge whether the threads are tightened in place.

[0005] The solution of the present invention is as follows:

[0006] A flexible tightening system for drill pipe thread connection, which successively sets a numerical control spiral milling machine, a fixed clamping device, a flexible threading device and a feeding device along the coaxial direction; a guiding device is also coaxially arranged between the fixed clamping device and the flexible threading device; a thread tightening detection device is arranged at the lower part on the side of the fixed clamping device, and a flexible threading floating device and an ultrasonic vibration device are arranged under the flexible threading device; the drill pipe to be processed is clamped and positioned by the numerical control spiral milling machine and the fixed clamping device, the drill pipe to be screwed is conveyed to the flexible threading device by the feeding device, and is coaxially docked with the drill pipe to be processed through the guiding device, and the flexible threading device screws the drill pipe to be processed and the drill pipe to be screwed; the thread tightening detection device detects whether the drill pipe to be processed and the drill pipe to be screwed are tightened, the flexible threading floating device finely adjusts the position of the flexible threading device, and the ultrasonic vibration device realizes the swing of the drill pipe to be screwed in the direction with the largest displacement deviation through resonance.

[0007] Optionally, the flexible threading device is provided with a frame, a guide rail is installed on the frame, a flexible threading device base is installed on the guide rail, a flexible threading floating device is arranged on the flexible threading device base, and a moving rotary chuck is carried on the flexible threading floating device; a three-jaw clamping pliers is arranged on one end face of the moving rotary chuck, and a reduction motor is arranged on the other end face; and a feed oil cylinder is arranged under the flexible threading device base.

[0008] Optionally, the flexible threading floating device is provided with a flexible floating device lower support plate, the flexible floating device lower support plate is fixedly installed on the flexible threading device base, two groups of spherical articulated studs are symmetrically distributed on the flexible floating device lower support plate, the lower end of the spherical articulated stud is spherically articulated with the flexible floating device lower support plate, and a spherical wear-resistant layer is arranged on the spherical articulated contact surface; the upper part of the spherical articulated stud is installed with a flexible floating device upper cover plate, there is a large annular space gap between the spherical articulated stud and the flexible floating device upper cover plate, and a group of double-top locking nuts are installed on the top of the spherical articulated stud to connect the flexible floating device upper cover plate and the flexible floating device lower support plate; between the flexible floating device upper cover plate and the flexible floating device lower support plate, a floating spring is installed, the center of the floating spring passes through the spherical articulated stud, and a limit sleeve ring is installed outside the floating spring; there is a gap between the limit sleeve ring and the floating spring, and there is also a gap with the flexible floating device upper cover plate.

[0009] Optionally, the fixed clamping device is provided with a fixed clamping support frame, and a fixed clamping support frame guide rail is arranged axially on the fixed clamping support frame; a fixed clamping box body is carried on the support frame guide rail and moves along the support frame guide rail, fixed clamping oil cylinders are respectively arranged at both ends of the fixed clamping box body, a V-shaped clamping pad is arranged at the end of the fixed clamping oil cylinder, and a chuck is installed on the clamping pad.

[0010] Optionally, the guiding device is provided with a first guiding ring and a second guiding ring arranged side by side at intervals; the first guiding ring guides the drill pipe to be screwed, the first guiding ring inlet guiding section of the first guiding ring is designed in a parabolic ring shape, and the first guiding ring limiting section is in a straight ring shape; the second guiding ring guides the drill pipe to be processed, the port guiding section of the second guiding ring is designed in a conical ring hole shape, the second guiding ring limiting section is in a straight ring shape, and the diameter of the second guiding ring limiting section is smaller than that of the first guiding ring limiting section.

[0011] Optionally, the thread tightening detection device mainly includes a sensor detection system and an optical detection system; in the sensor detection system, a pre-screwing sensor e, a post-screwing sensor f, a torque sensor g, and a screwing zero-point sensor h are sequentially installed on the flexible screwing device from front to back. Among them, the screwing zero-point sensor h is installed on the guide rail and is stationary, and the rest of the sensors can move back and forth with the moving and rotating chuck; the pre-screwing sensor e is located at the bottom of the moving and rotating chuck of the flexible screwing device, and the post-screwing sensor f is installed on the top of the moving and rotating chuck; a torque sensor is also installed on the floating screwing device to detect whether the torque of the moving and rotating chuck reaches the calibration value; a screwing zero-point sensor h is also installed at the rear end of the guide rail to detect whether the moving and rotating chuck moves to the rear end; a feeding sensor i is installed at the front end of the feeding device to detect whether there is a drill pipe to be screwed above it; in the sensor detection system, a clamping sensor a, a front fixed clamping device sensor b, and a rear fixed clamping device sensor c are sequentially installed on the fixed clamping device from front to back; the clamping sensor a is located on the fixed clamping device and is used to detect the opening and clamping states of a pair of jaws; a front fixed clamping device sensor b is provided on the top of the fixed clamping device, and a rear fixed clamping device sensor c is provided at the bottom of the fixed clamping device 3, mainly used to cooperate in detecting whether there is a drill pipe between the front fixed clamping device sensor b and the rear fixed clamping device sensor c; a distance sensor d is installed on the frame near the fixed clamping device, and the length measuring rope extended by the distance sensor d is fixedly installed on the flexible screwing device, and the position of the drill pipe is measured by the extended length measuring rope; the optical detection system is used to detect the deviation amount of the drill pipe to be screwed.

[0012] Optionally, the optical detection system includes a vision camera and a detection calibration point. The vision camera is installed under the fixed clamping device, and the detection calibration point is installed under the flexible screwing device; the vision camera and the detection calibration point are located on the projection line of the drill pipe axis.

[0013] Optionally, the ultrasonic vibration device includes a first ultrasonic vibrator and a second ultrasonic vibrator, which are fixedly and symmetrically installed under the flexible screwing device; the vibration frequency and vibration amplitude of the first ultrasonic vibrator and the second ultrasonic vibrator are controlled, and the drill pipe to be screwed is swung in the direction with the largest displacement deviation amount through resonance.

[0014] A detection and control method for drill pipe thread connection, which is realized by using the flexible tightening system for drill pipe thread connection described in the present invention, specifically includes the following steps:

[0015] Initial tightening:

[0016] (1) The feeding device transports the drill pipe to be made up forward. When the sensor after making up detects that there is a drill pipe, the feeding device immediately stops moving, and the moving and rotating chuck of the flexible making-up device clamps the drill pipe to be made up, realizing the initial alignment and positioning of the drill pipe to be made up;

[0017] (2) The flexible making-up device drives the drill pipe to be made up forward. When the sensor before making up detects that there is a drill pipe, the distance sensor records the rope length at this time as S1; the optical detection system detects that the deviation angle of the detection calibration point at this time is θ1;

[0018] (3) The flexible making-up device starts to advance spirally for making-up operation; when the torque sensor of the flexible making-up device detects that the torque is greater than the calibrated torque value, the flexible making-up device stops moving. At the same time, the distance sensor records the rope length at this time as S2; the optical detection system detects that the deviation angle of the detection calibration point at this time is θ2;

[0019] (4) Calculate the effective making-up length as S = |S1×cosθ1 - S2×cosθ2|, and calculate the error Δs = S - S0 between the measured effective making-up length and the calibrated effective making-up length. When Δs ≤ 0.3mm, it is considered that the drill pipe is tightened in place. The flexible making-up device releases the drill pipe to be made up and retreats to the rearmost end. The fixed clamping device releases the drill pipe to be processed, and the numerical control spiral milling machine starts the processing operation; otherwise, it is considered that the drill pipe is not tightened, an alarm is issued, and manual intervention is carried out;

[0020] The measuring method for the deviation angle θ of the detection calibration point detected by the optical detection system: After the sensor detection system gives a detection signal, the vision camera takes a picture of the position of the detection calibration point at this time. Through image processing and algorithms, the deviation direction and deviation amount of the detection calibration point relative to the coordinate origin in the radial direction of the drill pipe are determined.

[0021] The distance between the vision camera and the coordinate origin is S 原 ;

[0022] The deviation direction and deviation amount of the detection calibration point relative to the coordinate origin in the radial direction of the drill pipe are ΔS;

[0023] The value of the angle θ is:

[0024]

[0025] Among them, the measuring method for the value of S0:

[0026] For n drill pipes made up, record the effective making-up length each time as X1, X2…Xn;

[0027] The calculated effective calibration make-up length is:

[0028] Input the calculated effective calibration make-up length S0 into the control system;

[0029] Re-inspection:

[0030] When the milling machine control system simultaneously sends out a make-up signal and the milling machine rotating chuck reaches the front end limit signal, after completing the initial tightening step, the flexible make-up device clamps the drill pipe to be made up again, the milling machine rotating chuck of the CNC spiral milling machine clamps the drill pipe to be machined, and then the flexible make-up device rotates to make up again. When the torque sensor of the flexible make-up device detects that the torque is greater than the calibrated torque value, the flexible make-up device stops moving, and at the same time the distance sensor records the rope length at this time as S3; the optical detection system detects that the deviation angle of the detection calibration point at this time is θ3;

[0031] Calculate the re-tightening displacement S’, S’ = |S2×cosθ2 - S3×cosθ3|. When S’ ≤ 0.1 mm, it is considered that the multiple drill pipes for re-inspection have been tightened in place. The flexible make-up device releases the drill pipe to be made up, and the CNC spiral milling machine starts the machining operation; otherwise, it is considered that the drill pipe is not tightened, an alarm is issued, and manual intervention is carried out;

[0032] Ultrasonic vibration control: By receiving the deviation direction and deviation amount ΔS of the detection calibration point relative to the coordinate origin in the radial direction of the drill pipe from the visual detection system, the control center issues an instruction to control the vibration frequency and vibration amplitude of the first ultrasonic vibrator and the second ultrasonic vibrator, and realizes the swing of the drill pipe to be made up in the direction with the largest displacement deviation amount through resonance, and the swing amplitude is 1.5 - 2.5 times ΔS.

[0033] Compared with the prior art, the beneficial technical effects of the present invention are:

[0034] First, the automatic tightening device for drill pipe threads and the on-line detection and control method of the present invention realize the automation of the tightening process of the threads of two drill pipes during the milling spiral machining of the drill pipe, and can realize the on-line detection and control of the tightening.

[0035] Second, the automatic flexible tightening device for drill pipe threads of the present invention innovatively designs a flexible thread tightening system, which includes a guiding device, an ultrasonic vibration device, and a flexible thread tightening device. The guiding device ensures the success rate of the thread alignment of two drill pipes. The flexible tightening device enables the drill pipe to be tightened to be in a floating state during the thread tightening operation. The ultrasonic vibration device continuously vibrates repeatedly according to certain instructions to avoid problems such as thread jamming and incomplete tightening caused by the non-alignment of the two drill pipes. This flexible thread tightening system solves the problem of thread tightening failure caused by severe bending and high non-alignment degree of the two drill pipes, and greatly improves the success rate of thread tightening.

[0036] Third, the online detection and control method of the automatic flexible tightening device for drill pipe threads of the present invention innovatively combines the measurement of distance sensors with visual detection technology to realize the real-time detection of the thread tightening state. By calculating the detection data between the distance sensors and the data obtained from visual detection, it is determined whether the effective thread tightening length of the drill pipe is within the specified range of the calibrated effective thread tightening length to ensure that the drill pipe has been initially tightened in place. Through re-inspection, the re-tightening distance of multiple drill pipes between the milling machine rotating chuck and the thread tightening device is calculated. By determining whether the re-tightening distance is less than 0.1 mm, it is determined again whether the drill pipes are all tightened in place before milling processing, thereby realizing the online detection and control of drill pipe thread tightening.

[0037] Fourth, compared with other similar products, the automatic flexible tightening device for drill pipe threads and the online detection and control method of the present invention have the advantages of flexible tightening of drill pipe threads, online detection and control of thread tightening, high success rate of thread tightening, low price, good safety performance, high reliability, and online detection of tightening state. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 is a schematic diagram of the flexible tightening system for drill pipe thread connection of the present invention;

[0039] 1 - CNC spiral milling machine, 11 - milling machine rotating chuck, 12 - milling machine spiral feed guide rail, 2 - drill pipe, 21 - drill pipe to be processed, 22 - drill pipe to be tightened, 3 - fixed clamping device, 4 - flexible thread tightening device, 5 - feeding device, 51 - roller, 6 - flexible thread tightening floating device, 7 - ultrasonic vibration device, 8 - guiding device, 81 - second guiding ring, 82 - first guiding ring, 9 - thread tightening detection device;

[0040] Figure 2 is Figure 1 the structure diagram of the fixed clamping device in

[0041] 31 - Fixed clamping cylinder, 32 - Fixed clamping box body, 33 - Fixed clamping support frame, 34 - Fixed clamping support frame guide rail, 35 - Clamping cushion block, 36 - Chuck, 37 - Fixed clamping left and right limiters, 38 - Fixed clamping fixed seat;

[0042] Figure 3 is Figure 1 the structure diagram of the flexible make-up device in

[0043] 41 - Frame, 42 - Guide rail, 43 - Flexible make-up device base, 44 - Reducing motor, 45 - Moving rotary chuck, 46 - Three-jaw clamping pliers, 48 - Feed cylinder;

[0044] Figure 4 is Figure 1 the structure diagram of the flexible make-up floating device in

[0045] 61 - Double-top locking nut, 62 - Spherical articulated stud, 63 - Upper cover plate of flexible floating device, 64 - Limit sleeve ring, 65 - Floating spring, 66 - Spherical wear-resistant layer, 67 - Lower support plate of flexible floating device, 68 - Upper cover plate limit block of flexible floating device, 69 - Lower support plate baffle of flexible floating device

[0046] Figure 5 is Figure 1 the layout diagram of the ultrasonic vibration device and the thread tightening detection device in

[0047] 91 - Vision camera, 92 - Detection calibration point, 71 - First ultrasonic vibrator, 72 - Second ultrasonic vibrator, 73 - Control center;

[0048] Figure 6 is Figure 1 the structure diagram of the guiding device in

[0049] 811 - Second guide ring port guiding section, 812 - Second guide ring limiting section, 821 - First guide ring limiting section, 822 - First guide ring inlet guiding section;

[0050] Figure 7 is the distribution diagram of sensors in the flexible tightening system for drill pipe thread connection of the present invention;

[0051] a clamping sensor, b sensor before the fixed clamping device, c sensor after the fixed clamping device, d distance sensor, e sensor before make-up, f sensor after make-up, g torque sensor, h make-up zero point sensor, i feeding sensor. Detailed implementation manners

[0052] The following further describes the detailed implementation manners of the present invention with reference to the accompanying drawings.

[0053] Combined withFigure 1-7 For the flexible tightening system for drill pipe thread connection of the present invention, a numerical control spiral milling machine, a fixed clamping device, a flexible screwing device and a feeding device are sequentially arranged along the coaxial direction; a guiding device is also coaxially arranged between the fixed clamping device and the flexible screwing device; a thread tightening detection device is arranged at the lower part on the side of the fixed clamping device, and a flexible screwing floating device and an ultrasonic vibration device are arranged under the flexible screwing device; the drill pipe to be machined is clamped and positioned by the numerical control spiral milling machine and the fixed clamping device, the drill pipe to be screwed is conveyed to the flexible screwing device by the feeding device, and is coaxially docked with the drill pipe to be machined through the guiding device, and the flexible screwing device screws the drill pipe to be machined and the drill pipe to be screwed; the thread tightening detection device detects whether the drill pipe to be machined and the drill pipe to be screwed are tightened, the flexible screwing floating device finely adjusts the position of the flexible screwing device, and the ultrasonic vibration device realizes the swing of the drill pipe to be screwed in the direction with the largest displacement deviation through resonance.

[0054] Combined with Figure 3 For the flexible screwing device 4, a frame is provided, a guide rail is installed on the frame, a flexible screwing device base 43 is installed on the guide rail, a flexible screwing floating device 6 is arranged on the flexible screwing device base 43, and a moving rotary chuck 45 is carried on the flexible screwing floating device 6; a three-jaw clamping pliers 46 is arranged on one end face of the moving rotary chuck 45, and a reduction motor is arranged on the other end face; and a feed oil cylinder 48 is arranged under the flexible screwing device base 43. The flexible screwing device 4 is fixedly installed at the rear end of the frame 41, the flexible screwing floating device 6 is installed on the flexible screwing device base 43, and the flexible screwing device base 43 can move back and forth along the guide rail 42 installed on the frame 41. One end of the feed oil cylinder 48 is installed on the flexible screwing device base 43, and the other end is installed on the frame 41. The telescopic movement of the feed oil cylinder 48 drives the flexible screwing device 4 to move back and forth. The moving rotary chuck 45 is fixedly installed directly above the flexible screwing device 4, a reduction motor 44 is installed at the bottom of the moving rotary chuck 45, and a group of three-jaw clamping pliers 46 are evenly installed on the side of the moving rotary chuck 45 for clamping the drill pipe 22 to be screwed.

[0055] Combined with Figure 4, the flexible make-up floating device 6 is provided with a flexible floating device lower support plate 67. The flexible floating device lower support plate 67 is fixedly installed on the flexible make-up device base 43. Two groups of spherical articulated studs 62 are symmetrically distributed on the flexible floating device lower support plate 67. The lower end of the spherical articulated stud 62 is spherically articulated with the flexible floating device lower support plate 67, and a spherical wear-resistant layer 665 is provided on the spherical articulated contact surface; the upper part of the spherical articulated stud 62 is installed with a flexible floating device upper cover plate 63. There is a large annular space gap between the spherical articulated stud 62 and the flexible floating device upper cover plate 63. The top of the spherical articulated stud 62 is installed with a set of double-top locking nuts 61 to connect the flexible floating device upper cover plate 63 and the flexible floating device lower support plate 67; between the flexible floating device upper cover plate 63 and the flexible floating device lower support plate 67, a floating spring 65 is installed. The center of the floating spring 65 passes through the spherical articulated stud 62, and a limit sleeve ring 64 is installed outside the floating spring 65; there is a gap between the limit sleeve ring 64 and the floating spring 65, and there is also a gap with the flexible floating device upper cover plate 63. Specifically, the flexible floating device lower support plate 67 is fixedly installed on the flexible make-up device base 43. Two groups of spherical articulated studs 62 are symmetrically distributed on the flexible floating device lower support plate 67. The lower end of the spherical articulated stud 62 is spherically articulated with the flexible floating device lower support plate 67, and a spherical wear-resistant layer 665 is provided on the spherical articulated contact surface; the upper part of the spherical articulated stud 62 is installed with a flexible floating device upper cover plate 63. There is a large annular space gap between the spherical articulated stud 62 and the flexible floating device upper cover plate 63. The top of the spherical articulated stud 62 is installed with a set of double-top locking nuts 61 to connect the flexible floating device upper cover plate 63 and the flexible floating device lower support plate 67; between the flexible floating device upper cover plate 63 and the flexible floating device lower support plate 67, a floating spring 65 is installed. The center of the floating spring 65 passes through the spherical articulated stud 62, and a limit sleeve ring 64 is installed outside the floating spring 65. There is a certain gap between the limit sleeve ring 64 and the floating spring 65, and there is also a large gap with the flexible floating device upper cover plate 63. The limit sleeve ring 64 is mainly used to limit the movement displacement amplitude of the flexible floating device upper cover plate 63 in the front-back, up-down, and left-right directions; by adjusting the double-top locking nuts 61, the compression amount of the floating spring 65 is controlled to ensure that the flexible floating device upper cover plate 63 can achieve vertical movement within a limited range, making it have a certain flexibility in the vertical direction.At the front end of the upper cover plate 63 of the flexible floating device, a limit block 68 of the upper cover plate of the flexible floating device is installed. At the front end of the lower support plate 67 of the flexible floating device, a baffle 69 of the lower support plate of the flexible floating device is installed. When the limit block 68 of the upper cover plate of the flexible floating device moves to the position of the baffle 69 of the lower support plate of the flexible floating device, the limit block 68 of the upper cover plate of the flexible floating device is horizontally limited and no longer moves backward, thereby restricting the horizontal movement range of the flexible screwing device 4; during the screwing operation, the horizontal thrust of the feed oil cylinder 48 is transmitted to the limit block 68 of the upper cover plate of the flexible floating device through the baffle 69 of the lower support plate of the flexible floating device. By using the limit block 68 of the upper cover plate of the flexible floating device and the baffle 69 of the lower support plate of the flexible floating device in cooperation, the movement of the flexible screwing floating device 6 in the backward direction is restricted.

[0056] Combined with Figure 2 , the fixed clamping device 3 is provided with a fixed clamping support frame 33, and a fixed clamping support frame guide rail 34 is axially arranged on the fixed clamping support frame 33; a fixed clamping box body 32 is carried on the support frame guide rail 34 and moves along the support frame guide rail 34. Fixed clamping oil cylinders 31 are respectively arranged at both ends of the fixed clamping box body 32, and a V-shaped clamping pad 35 is arranged at the end of the fixed clamping oil cylinder 31, and a slip joint 36 is installed on the clamping pad 35. Specifically, the fixed clamping device 3 is fixedly installed at the front end of the frame 41, the fixed clamping support frames 33 are installed in pairs on the frame 41, and a group of fixed clamping support frame guide rails 34 are arranged in the middle of the fixed clamping support frames 33. The fixed clamping box body 32 can only move freely left and right on the fixed clamping support frame guide rail 34, and fixed clamping left and right limiters 37 are respectively installed at the left and right ends of the fixed clamping box body 32 to limit the left and right movement range of the fixed clamping device 3. Fixed clamping oil cylinders 31 are respectively fixedly installed at the left and right ends of the fixed clamping box body 32, a clamping pad 35 is fixedly installed at the rod end of the fixed clamping oil cylinder 31, and a slip joint 36 is installed on the clamping pad 35. The telescopic movement of the fixed clamping oil cylinder 31 drives the slip joint 36 to clamp and loosen through the clamping pad 35, thereby realizing the clamping and loosening of the drill pipe 21 to be processed.

[0057] The guiding device 8 is located between the fixed clamping device 3 and the flexible screwing device 4. The guiding device 8 mainly includes a first guiding ring 82 and a second guiding ring 81, and the first guiding ring 82 is located at the rear end of the second guiding ring 81; the first guiding ring inlet guiding section 822 of the first guiding ring 82 is designed in a parabolic ring shape, and the first guiding ring limiting section 821 is in a straight ring shape. The first guiding ring 82 is mainly used to guide the drill pipe 22 to be screwed. The second guiding ring port guiding section 811 is designed in a conical ring hole shape, the second guiding ring limiting section 812 is in a straight ring shape, and the diameter of the second guiding ring limiting section 812 is smaller than the diameter of the first guiding ring limiting section 821.

[0058] The thread tightening detection device 9 mainly includes a sensor detection system and an optical detection system.

[0059] The sensors mainly include: the clamp-on sensor a, the sensor b in front of the fixed clamping device, the sensor c behind the fixed clamping device, the distance sensor d, the sensor e before screwing, the sensor f after screwing, the torque sensor g, the zero-point sensor h for screwing, and the feeding sensor i.

[0060] The sensor detection system successively installs the sensor e before screwing, the sensor f after screwing, the torque sensor g, and the zero-point sensor h for screwing on the flexible screwing device 4 from front to back. Among them, the zero-point sensor h for screwing is installed on the guide rail 42 and remains stationary, and the other sensors can move back and forth together with the moving rotary chuck 45. The sensor e before screwing is located at the bottom of the moving rotary chuck 45 of the flexible screwing device 4, and the sensor f after screwing is installed on the top of the moving rotary chuck 45; a torque sensor is also installed on the floating screwing device 4 to detect whether the torque of the moving rotary chuck 45 reaches the calibrated value; the zero-point sensor h for screwing is also installed at the rearmost end of the guide rail 42 to detect whether the moving rotary chuck 45 moves to the rearmost end. The feeding sensor i is installed at the front end of the feeding device 5 to detect whether there is a drill pipe 22 to be screwed above it.

[0061] The sensor detection system successively installs the clamp-on sensor a, the sensor b in front of the fixed clamping device, and the sensor c behind the fixed clamping device on the fixed clamping device 3 from front to back. The clamp-on sensor a is located on the fixed clamping device 3 and is used to detect the opening and clamping states of a pair of jaws 36; the sensor b in front of the fixed clamping device is provided at the top of the fixed clamping device 3, and the sensor c behind the fixed clamping device is provided at the bottom of the fixed clamping device 3, mainly used to cooperate in detecting whether there is a drill pipe between the sensor b in front of the fixed clamping device and the sensor c behind the fixed clamping device; the distance sensor d is installed on the frame 41 close to the fixed clamping device 3, and the length measuring rope extended by the distance sensor d is fixedly installed on the upper cover plate 63 of the flexible floating device of the flexible screwing device 4, and the position of the drill pipe is measured by the extended length measuring rope.

[0062] The optical detection system is installed on the thread tightening detection device 9, including a vision camera 91 and a detection calibration point 92. The vision camera 91 is installed directly below the central axis of the fixed clamping device 3, and the detection calibration point 92 is installed directly below the central axis of the flexible screwing floating device 6.

[0063] The ultrasonic vibration device 7 is fixedly and symmetrically installed on the base 43 of the flexible screwing device, mainly including a first ultrasonic vibrator 71 and a second ultrasonic vibrator 72. The control center 73 obtains the deviation amount of the calibration point through the optical detection system, and issues instructions to control the vibration frequency and amplitude of the first ultrasonic vibrator 71 and the second ultrasonic vibrator 72 respectively, so as to realize the swing of the drill pipe 22 to be screwed in the direction with the largest displacement deviation amount.

[0064] The thread tightening control method of the present invention mainly determines whether the threads between the drill pipes are tightened in place according to the following rules:

[0065] The specific steps are as follows:

[0066] 1. Initial tightening

[0067] (1) When the milling machine control system of the numerical control spiral milling machine 1 issues a make-up signal, when the sensor b in front of the fixed clamping device detects the drill pipe 21 to be processed, and the sensor c behind the fixed clamping device detects that there is no drill pipe 21 to be processed, it proves that the drill pipe 21 to be processed falls within the specified range, and the system will perform the next action; otherwise, it proves that the drill pipe 21 to be processed exceeds the specified range, and the PLC control system alarms for manual intervention.

[0068] (2) When the feeding sensor i detects that there is no drill pipe 22 to be screwed, feeding is performed; when the feeding sensor i detects the drill pipe 22 to be screwed, and the sensor c behind the fixed clamping device detects that there is no drill pipe 21 to be processed, and the screwing zero point sensor h detects that the flexible screwing device 4 is at the rearmost end, the feeding device 5 conveys the drill pipe 22 to be screwed forward;

[0069] (3) When the sensor f after screwing detects the drill pipe 22 to be screwed, the feeding device 5 immediately stops moving, and the tightening chuck 41 of the flexible screwing device 4 clamps the drill pipe 22 to be screwed, realizing the initial alignment and positioning of the drill pipe 22 to be screwed.

[0070] (4) The flexible screwing device 4 continues to drive the drill pipe 22 to be screwed forward. When the sensor e before screwing detects the drill pipe 22 to be screwed (that is, detects the end face 21 of the drill pipe to be processed by the milling machine), the distance sensor d records the rope length at this time as S1;

[0071] (5) The flexible screwing device 4 starts to screw forward for the screwing operation. At the same time, the optical detection system 10 detects the deviation angle θ1 of the detection calibration point 92 at this time, calculates the radial deviation amount and deviation direction of the central axis of the detection calibration point 92 through the control center 73, and issues instructions to control the vibration frequency and amplitude of the first ultrasonic vibrator 71 and the second ultrasonic vibrator 72;

[0072] (4) When the torque sensor g of the flexible make-up device 4 detects that the torque is greater than the calibrated torque value, the flexible make-up device 4 stops moving. At the same time, the distance sensor d records the rope length at this time as S2, and the optical detection system 10 detects the deviation angle θ2 of the detection calibration point 92 at this time; the calibrated torque value is a set value, that is, the designed pre-tightening torque value of the drill pipe.

[0073] (5) The PLC control system calculates the effective make-up length as S = |S1×cosθ1 - S2×cosθ2|, calculates the error Δs = S - S0 between the measured effective make-up length and the calibrated effective make-up length. When Δs ≤ 0.3 mm, it is considered that the drill pipe 22 to be made up is tightened in place. The flexible make-up device 4 releases the drill pipe 22 to be made up and retreats to the rearmost end. The fixed clamping device 3 releases the drill pipe 21 to be machined, and the numerical control spiral milling machine 1 starts the machining operation; otherwise, it is considered that the drill pipe 22 to be made up is not tightened, an alarm is issued, and manual intervention is carried out.

[0074] Method for measuring the deviation angle θ of the detection calibration point 92 detected by the optical detection system:

[0075] After the sensor detection system gives a detection signal, the vision camera 91 takes a picture of the position of the detection calibration point 92 at this time. Through image processing and algorithms, the deviation direction and deviation amount of the detection calibration point 92 relative to the coordinate origin in the radial direction of the drill pipe are determined.

[0076] The distance between the vision camera 91 and the coordinate origin is S 原 ;

[0077] The deviation direction and deviation amount of the detection calibration point 92 relative to the coordinate origin in the radial direction of the drill pipe are ΔS;

[0078] The value of the angle θ is:

[0079]

[0080] Method for measuring the value of S0:

[0081] Manually jog the PLC control system (control center 73), automatically tighten n drill pipes 22 to be tightened, and record the effective make-up length each time as X1, X2…Xn;

[0082] Calculate the calibrated effective make-up length as:

[0083] Input the calculated calibrated effective make-up length S0 into the PLC control system (control center 73).

[0084] 2. Re-inspection

[0085] When the CNC spiral milling machine control system simultaneously sends out the make-up signal and the signal that the milling machine rotating chuck 11 reaches the front end limit, after the PLC control system completes the initial tightening step, the flexible make-up device 4 clamps the drill pipe 22 to be made up again, and the milling machine rotating chuck 11 of the CNC spiral milling machine 1 clamps the drill pipe 22 to be machined. Then, the flexible make-up device 4 rotates and makes up again. When the torque sensor g of the flexible make-up device 4 detects that the torque is greater than the calibrated torque value, the flexible make-up device 4 stops moving. At the same time, the distance sensor d records the rope length at this time as S3, and the optical detection system 10 detects that the deviation angle of the detection calibration point 92 at this time is θ3. The PLC control system calculates the re-tightening displacement S’, S’ = |S2×cosθ2 - S3×cosθ3|. When S’ ≤ 0.1 mm, it is considered that the multiple drill pipes for re-inspection have been tightened in place (the drill pipes for re-inspection are multiple drill pipes between the milling machine rotating chuck 11 and the flexible make-up device 4). The flexible make-up device 4 releases the drill pipe 22 to be made up, and the CNC spiral milling machine 1 starts the processing operation; otherwise, it is considered that the drill pipe is not tightened, an alarm is issued, and manual intervention is carried out.

[0086] 3. Ultrasonic vibration control

[0087] The control center 73 receives the deviation direction and deviation amount ΔS of the detection calibration point 92 relative to the coordinate origin in the radial direction of the drill pipe obtained by the visual detection system 10. The control center 73 issues an instruction to control the vibration frequency and vibration amplitude of the first ultrasonic vibrator 71 and the second ultrasonic vibrator 72, and realizes the swing of the drill pipe 22 to be made up in the direction with the largest displacement deviation amount through resonance, and the swing amplitude is 1.5 - 2.5 times ΔS.

[0088] The preferred embodiments of the present disclosure have been described in detail above. However, the present disclosure is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.

[0089] In addition, it should be noted that, among the various specific technical features described in the above specific embodiments, they can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present disclosure will not separately describe various possible combination methods.

[0090] In addition, any combination can be made between various different embodiments of the present disclosure, as long as it does not violate the idea of the present disclosure, it should also be regarded as the content disclosed by the present disclosure.

Claims

1. A flexible tightening system for drill pipe thread connection, characterized in that, A numerically controlled spiral milling machine (1), a fixed clamping device (3), a flexible threading device (4) and a feeding device (5) are sequentially arranged along the coaxial direction; A guiding device (8) is also coaxially arranged between the fixed clamping device (3) and the flexible threading device (4); A thread tightening detection device (9) is arranged at the lower part on the side of the fixed clamping device (3), and a flexible threading floating device (6) and an ultrasonic vibration device (7) are arranged under the flexible threading device (4); The drill pipe to be machined (21) is clamped and positioned by the numerically controlled spiral milling machine (1) and the fixed clamping device (3), the drill pipe to be screwed (22) is conveyed to the flexible threading device (4) by the feeding device (5), and is coaxially docked with the drill pipe to be machined (21) through the guiding device (8), and the flexible threading device (4) screws the drill pipe to be machined (21) and the drill pipe to be screwed (22); The thread tightening detection device (9) detects whether the drill pipe to be machined (21) and the drill pipe to be screwed (22) are tightened, the flexible threading floating device (6) fine-tunes the position of the flexible threading device (4), and the ultrasonic vibration device (7) makes the drill pipe to be screwed (22) swing in the direction with the largest displacement deviation through resonance; The flexible threading device (4) is provided with a frame (41), a guide rail (42) is installed on the frame (41), a flexible threading device base (43) is installed on the guide rail (42), a flexible threading floating device (6) is arranged on the flexible threading device base (43), and a moving rotary chuck (45) is carried on the flexible threading floating device (6); a three-jaw clamping pliers (46) is arranged on one end face of the moving rotary chuck (45), and a reduction motor (44) is arranged on the other end face; and a feed oil cylinder (48) is arranged under the flexible threading device base (43); The flexible threading floating device (6) is provided with a flexible floating device lower support plate (67), the flexible floating device lower support plate (67) is fixedly installed on the flexible threading device base (43), two groups of spherical articulated studs (62) are symmetrically distributed on the flexible floating device lower support plate (67), the lower end of the spherical articulated stud (62) is spherically articulated with the flexible floating device lower support plate (67), and a spherical wear-resistant layer (66) is arranged on the spherical articulated contact surface; the upper part of the spherical articulated stud (62) is provided with a flexible floating device upper cover plate (63), there is an annular space gap between the spherical articulated stud (62) and the flexible floating device upper cover plate (63), a group of double-top locking nuts (61) are installed on the top of the spherical articulated stud (62) to connect the flexible floating device upper cover plate (63) and the flexible floating device lower support plate (67); between the flexible floating device upper cover plate (63) and the flexible floating device lower support plate (67), a floating spring (65) is installed, the center of the floating spring (65) passes through the spherical articulated stud (62), and a limiting sleeve ring (64) is installed outside the floating spring (65); There are gaps between the limiting sleeve ring (64), the floating spring (65) and the flexible floating device upper cover plate (63).

2. The flexible tightening system for drill pipe thread connection according to claim 1, characterized in that The described fixed clamping device (3) is provided with a fixed clamping support frame (33), and a fixed clamping support frame guide rail (34) is axially arranged on the fixed clamping support frame (33); a fixed clamping box body (32) is carried on the support frame guide rail (34) and moves along the support frame guide rail (34). Fixed clamping oil cylinders (31) are respectively arranged at both ends of the fixed clamping box body (32), and a V-shaped clamping pad block (35) is arranged at the end of the fixed clamping oil cylinder (31), and a chuck (36) is installed on the clamping pad block (35).

3. The flexible tightening system for drill pipe thread connection according to claim 1 or 2, characterized in that, The described guiding device (8) is provided with a first guiding ring (82) and a second guiding ring (81) arranged side by side at intervals; The first guiding ring (82) guides the drill pipe to be made up (22). The first guiding ring inlet guiding section (822) of the first guiding ring (82) is designed in a parabolic ring shape, and the first guiding ring limiting section (821) is in a straight ring shape; The second guiding ring (81) guides the drill pipe to be processed (21). The second guiding ring port guiding section (811) is in a conical ring hole shape, and the second guiding ring limiting section (812) is set in a straight ring shape, and the diameter of the second guiding ring limiting section (812) is smaller than the diameter of the first guiding ring limiting section (821).

4. The flexible tightening system for drill pipe thread connection according to claim 1 or 2, characterized in that, The thread tightening detection device (9) mainly includes a sensor detection system and an optical detection system; In the sensor detection system, a pre-threading sensor (e), a post-threading sensor (f), a torque sensor (g) and a threading zero point sensor (h) are sequentially installed on the flexible threading device (4) from front to back. Among them, the threading zero point sensor (h) is installed on the guide rail (42) and is fixed. The rest of the sensors can move back and forth together with the moving and rotating chuck (45); the pre-threading sensor (e) is located at the bottom of the moving and rotating chuck (45) of the flexible threading device (4), and a post-threading sensor (f) is installed on the top of the moving and rotating chuck (45); a torque sensor (g) is also installed on the flexible threading device (4) to detect whether the torque of the moving and rotating chuck (45) reaches the calibration value; a threading zero point sensor (h) is also installed at the rearmost end of the guide rail (42) to detect whether the moving and rotating chuck (45) moves to the rearmost end; a feeding sensor (i) is installed at the front end of the feeding device (5) to detect whether there is a drill pipe to be made up (22) above it; The sensor detection system is successively installed with a pair clamping sensor (a), a front fixed clamping device sensor (b), and a rear fixed clamping device sensor (c) on the fixed clamping device (3) from front to back; the pair clamping sensor (a) is located on the fixed clamping device (3) and is used to detect the opening and clamping states of a pair of slips (36); a front fixed clamping device sensor (b) is provided at the top of the fixed clamping device (3), and a rear fixed clamping device sensor (c) is provided at the bottom of the fixed clamping device (3), which are used to cooperate in detecting whether there is a drill pipe between the front fixed clamping device sensor (b) and the rear fixed clamping device sensor (c); a distance sensor (d) is installed on the frame (41) close to the fixed clamping device (3), and the length measuring rope extended by the distance sensor (d) is fixedly installed on the flexible make-up device (4), and the position of the drill pipe is determined by the extended length measuring rope. The optical detection system is used to detect the deviation amount of the drill pipe (22) to be made up.

5. The flexible tightening system for drill pipe thread connection according to claim 4, characterized in that, The optical detection system includes a vision camera (91) and a detection calibration point (92). The vision camera (91) is installed under the fixed clamping device (3), and the detection calibration point (92) is installed under the flexible make-up device (4). The vision camera (91) and the detection calibration point (92) are located on the projection line of the drill pipe axis.

6. The flexible tightening system for drill pipe thread connection according to claim 1 or 2, characterized in that, The ultrasonic vibration device (7) includes a first ultrasonic vibrator (71) and a second ultrasonic vibrator (72), which are fixedly and symmetrically installed under the flexible make-up device (4). Control the vibration frequency and vibration amplitude of the first ultrasonic vibrator (71) and the second ultrasonic vibrator (72), and swing the drill pipe (22) to be made up in the direction with the largest displacement deviation amount through resonance.

7. The flexible tightening system for drill pipe thread connection according to claim 1, wherein The flexible make-up device (4) is provided with a frame (41). A guide rail (42) is installed on the frame (41), a flexible make-up device base (43) is installed on the guide rail (42), a flexible make-up floating device (6) is provided on the flexible make-up device base (43), and a moving rotary chuck (45) is carried on the flexible make-up floating device (6); a three-jaw clamping pliers (46) is provided on one end face of the moving rotary chuck (45), and a reduction motor (44) is provided on the other end face; and a feed oil cylinder (48) is provided under the flexible make-up device base (43). The described flexible make-up floating device (6) is provided with a flexible floating device lower support plate (67). The flexible floating device lower support plate (67) is fixedly installed on the flexible make-up device base (43). Two groups of spherical articulated studs (62) are symmetrically distributed on the flexible floating device lower support plate (67). The lower end of the spherical articulated stud (62) is spherically articulated with the flexible floating device lower support plate (67), and a spherical wear-resistant layer (66) is provided on the spherical articulated contact surface. The upper part of the spherical articulated stud (62) is installed with a flexible floating device upper cover plate (63). There is an annular gap between the spherical articulated stud (62) and the flexible floating device upper cover plate (63). A group of double-top locking nuts (61) are installed at the top of the spherical articulated stud (62) to connect the flexible floating device upper cover plate (63) and the flexible floating device lower support plate (67). Between the flexible floating device upper cover plate (63) and the flexible floating device lower support plate (67), a floating spring (65) is installed. The center of the floating spring (65) passes through the spherical articulated stud (62), and a limiting sleeve ring (64) is installed outside the floating spring (65). There are gaps between the limiting sleeve ring (64), the floating spring (65), and the flexible floating device upper cover plate (63). The described fixed clamping device (3) is provided with a fixed clamping support frame (33). The fixed clamping support frame (33) is axially provided with a fixed clamping support frame guide rail (34). A fixed clamping box body (32) is carried on the support frame guide rail (34) and moves along the support frame guide rail (34). Fixed clamping cylinders (31) are respectively arranged at both ends of the fixed clamping box body (32). A V-shaped clamping pad (35) is arranged at the end of the fixed clamping cylinder (31), and a slip-on (36) is installed on the clamping pad (35). The described guiding device (8) is provided with a first guiding ring (82) and a second guiding ring (81) arranged side by side at intervals. The first guiding ring (82) guides the drill pipe to be made up (22). The first guiding ring inlet guiding section (822) of the first guiding ring (82) is designed in a parabolic ring shape, and the first guiding ring limiting section (821) is in a straight ring shape. The second guiding ring (81) guides the drill pipe to be processed (21). The second guiding ring port guiding section (811) is in a conical ring hole shape, and the second guiding ring limiting section (812) is set in a straight ring shape, and the diameter of the second guiding ring limiting section (812) is smaller than the diameter of the first guiding ring limiting section (821). The thread tightening detection device (9) mainly includes a sensor detection system and an optical detection system. The sensor detection system is successively installed with a pre - screwing sensor (e), a post - screwing sensor (f), a torque sensor (g), and a screwing zero - point sensor (h) on the flexible screwing device (4) from front to back. Among them, the screwing zero - point sensor (h) is installed on the guide rail (42) and is stationary, and the other sensors can move back and forth together with the moving and rotating chuck (45). The pre - screwing sensor (e) is located at the bottom of the moving and rotating chuck (45) of the flexible screwing device (4), and the post - screwing sensor (f) is installed on the top of the moving and rotating chuck (45). A torque sensor (g) is also installed on the flexible screwing device (4) to detect whether the torque of the moving and rotating chuck (45) reaches the calibrated value. A screwing zero - point sensor (h) is also installed at the rearmost end of the guide rail (42) to detect whether the moving and rotating chuck (45) moves to the rearmost end. A feeding sensor (i) is installed at the front end of the feeding device (5) to detect whether there is a drill pipe to be screwed above it. The sensor detection system is successively installed with a clamping sensor (a), a pre - fixed - clamping - device sensor (b), and a post - fixed - clamping - device sensor (c) on the fixed - clamping device (3) from front to back. The clamping sensor (a) is located on the fixed - clamping device (3) and is used to detect the opening and clamping states of a pair of slips (36). A pre - fixed - clamping - device sensor (b) is provided at the top of the fixed - clamping device (3), and a post - fixed - clamping - device sensor (c) is provided at the bottom of the fixed - clamping device (3) to cooperate in detecting whether there is a drill pipe between the pre - fixed - clamping - device sensor (b) and the post - fixed - clamping - device sensor (c). A distance sensor (d) is installed on the frame (41) near the fixed - clamping device (3). The length - measuring rope extended by the distance sensor (d) is fixedly installed on the flexible screwing device (4), and the position of the drill pipe is determined by the extended length - measuring rope. The described optical detection system includes a vision camera (91) and a detection calibration point (92). The vision camera (91) is installed under the fixed - clamping device (3), and the detection calibration point (92) is installed under the flexible screwing device (4). The vision camera (91) and the detection calibration point (92) are located on the projection line of the drill - pipe axis. The described ultrasonic vibration device (7) includes a first ultrasonic vibrator (71) and a second ultrasonic vibrator (72), which are fixedly and symmetrically installed under the flexible screwing device (4). The vibration frequency and vibration amplitude of the first ultrasonic vibrator (71) and the second ultrasonic vibrator (72) are controlled, and the drill pipe to be screwed (22) is swung in the direction with the largest displacement deviation through resonance.

8. A detection and control method for drill pipe thread connection, characterized in that, It is realized by using the flexible tightening system for drill - pipe thread connection described in claim 7, specifically including the following steps: Initial tightening: (1) The feeding device (5) conveys the drill pipe to be screwed (22) forward. When the post - screwing sensor (f) detects a drill pipe, the feeding device (5) immediately stops moving, and the moving and rotating chuck (45) clamps the drill pipe to be screwed (22) to achieve the initial alignment and positioning of the drill pipe to be screwed (22). (2) The flexible make-up device (4) drives the drill pipe to be made up (22) to move forward. When the make-up pre-sensor (e) detects a drill pipe, the distance sensor (d) records the rope length at this time as S1; the optical detection system detects that the deviation angle of the detection calibration point (92) is θ1 at this time. (3) The flexible make-up device (4) starts to advance in a spiral for make-up operation; when the torque sensor (g) of the flexible make-up device (4) detects that the torque is greater than the calibrated torque value, the flexible make-up device (4) stops moving. At the same time, the distance sensor (d) records the rope length at this time as S2; the optical detection system detects that the deviation angle of the detection calibration point (92) is θ2 at this time. (4) Calculate the effective length of the make-up as S = |S1×cosθ1 - S2×cosθ2|, and calculate the error between the measured effective length of the make-up and the calibrated effective length of the make-up. When , it is considered that the drill pipe is tightened in place. The flexible make-up device (4) releases the drill pipe to be made up (22) and retracts to the rearmost end. The fixed clamping device (3) releases the drill pipe to be processed (21), and the CNC spiral milling machine (1) starts the processing operation; otherwise, it is considered that the drill pipe is not tightened, an alarm is issued, and manual intervention is carried out. Method for measuring the deviation angle θ of the detection calibration point (92) detected by the optical detection system: After the sensor detection system gives a detection signal, the vision camera (91) takes a picture of the position of the detection calibration point (92) at this time. Through image processing and algorithms, the deviation direction and deviation amount of the detection calibration point (92) relative to the coordinate origin in the radial direction of the drill pipe are determined. The distance between the vision camera (91) and the origin of coordinates is S 原 ; The deviation direction and deviation amount of the detection calibration point (92) relative to the coordinate origin in the radial direction of the drill pipe are ΔS. The value of the angle θ is: ； Among them, the method for measuring the value of S0: There are n drill pipes for make-up, and record the effective make-up length each time as X1, X2... Xn; The calculated effective length of calibration make-up is: ; Input the calculated calibrated effective make-up length S0 into the control system. Re-inspection: When the milling machine control system simultaneously sends a make-up signal and the milling machine rotating chuck reaches the front end limit signal, after completing the initial tightening step, the flexible make-up device (4) clamps the drill pipe to be made up (22) again, and the milling machine rotating chuck (11) of the CNC spiral milling machine (1) clamps the drill pipe to be machined (21). Then the flexible make-up device (4) rotates for make-up again. When the torque sensor (g) of the flexible make-up device (4) detects that the torque is greater than the calibrated torque value, the flexible make-up device (4) stops moving. At the same time, the distance sensor (d) records the rope length at this time as S3; the optical detection system detects that the deviation angle of the detection calibration point (92) is θ3 at this time. Calculate the re-tightening displacement S’, S’ = |S2×cosθ2 - S3×cosθ3|. When S’ ≤ 0.1mm, it is considered that the multiple drill pipes for re-inspection have been tightened in place. The flexible make-up device (4) releases the drill pipe to be made up (22), and the CNC spiral milling machine (1) starts the machining operation; otherwise, it is considered that the drill pipe is not tightened, an alarm is issued, and manual intervention is carried out. Ultrasonic vibration control: By receiving the deviation direction and deviation amount ΔS of the detection calibration point (92) relative to the coordinate origin in the radial direction of the drill pipe obtained by the vision detection system, the control center issues an instruction to control the vibration frequency and vibration amplitude of the first ultrasonic vibrator (71) and the second ultrasonic vibrator (72), and realizes the swing of the drill pipe to be made up (22) in the direction with the largest displacement deviation amount through resonance, and the swing amplitude is 1.5 - 2.5 times ΔS.

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