Intelligent high-speed laser welding device for longitudinal welded pipe

Abstract

The invention belongs to the technical field of welding equipment, and particularly relates to an intelligent high-speed laser welding device for a longitudinal welded pipe, which comprises a rack, a high-precision clamping mechanism, a multi-degree-of-freedom motion platform, a laser welding head and an intelligent control system. The clamping mechanism adopts hydraulic pressure to drive an arc-shaped clamping plate to realize self-adaptive centering and flexible clamping of the pipe fitting; an X-direction module of the motion platform adopts a servo motor to be matched with a synchronous belt (or a ball screw) for transmission, and a Y-direction module is driven by a hydraulic cylinder, so that precise track control of the laser welding head is jointly realized; the intelligent control system integrates visual tracking of welding seams, infrared monitoring of a molten pool and laser detection of deformation, and welding parameters and motion trails are dynamically adjusted by calculating a welding quality coefficient in real time and based on a threshold value and a residence criterion. According to the method, the problems of welding seam tracking lag, unstable molten pool state, thermal deformation compensation deficiency and the like in high-speed welding are solved, and self-adaptive optimization and full data tracing in the welding process are achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of welding equipment, in particular to an intelligent high-speed laser welding device for straight seam welded pipes. BACKGROUND

[0002] Straight seam welded pipes are key components in the fields of oil and gas transportation and building structures, and the quality of the welds directly affects the pressure-bearing capacity and service life of the pipes. Laser welding has become the mainstream process for manufacturing high-quality straight seam welded pipes due to its high energy density, small heat-affected zone, and high speed.

[0003] However, during high-speed continuous welding, there are still many technical challenges:

[0004] (1) Insufficient weld tracking accuracy: deviations are inevitable in pipe preassembly or butt joining, and traditional preset trajectory welding cannot correct in real time, which easily leads to misalignment or incomplete penetration;

[0005] (2) Unknown welding process state: the molten pool in laser welding changes dramatically, and there is a lack of effective online monitoring means. Once the welding parameters (power, speed, and defocusing amount) are set, they are fixed and cannot be adjusted adaptively according to the actual state of the molten pool (such as molten width, molten depth, and temperature uniformity). When the pipe thickness changes or there is a slight edge misalignment, the welding quality fluctuates greatly;

[0006] (3) Heat deformation impact is not compensated: local high heat input during welding can cause longitudinal shrinkage and transverse bending of the pipe, which changes the actual spatial position of the weld. The traditional rigid motion platform cannot compensate for this online, leading to trajectory deviation in the middle and later stages of welding;

[0007] (4) Lack of intelligent decision-making and traceability system: existing equipment relies on operator experience to set parameters, and process data records are incomplete, making it difficult to trace the root cause when quality problems occur, and the process optimization period is long.

[0008] Therefore, there is an urgent need for an intelligent high-speed laser welding device that integrates high-precision real-time tracking, multi-state perception, adaptive control, and full-data-chain traceability to improve the welding quality consistency, production efficiency, and process controllability of straight seam welded pipes. SUMMARY

[0009] Based on the technical problems existing in the prior art, the present application provides an intelligent high-speed laser welding device for straight seam welded pipes.

[0010] The intelligent high-speed laser welding device for straight seam welded pipes provided by the present application comprises a rack, a clamping mechanism, a motion platform, a laser welding head, a human-computer interaction interface, a data management module, and an intelligent control system.

[0011] The rack is the load-bearing main body of the device;

[0012] A clamping mechanism is installed on the frame for fixing the pipe to be welded, which comprises a pair of oppositely arranged arc-shaped clamping plates, one of which is a fixed arc-shaped clamping plate and the other is a movable arc-shaped clamping plate, the movable arc-shaped clamping plate is connected to the piston rod end of the hydraulic cylinder I and is driven by the hydraulic cylinder I to achieve clamping and loosening;

[0013] A motion platform is installed on the frame above the clamping mechanism for driving the welding executor to move in two dimensions;

[0014] A laser welding head is installed at the motion end of the motion platform as a welding executor for emitting a laser beam;

[0015] An intelligent control system is electrically connected with the clamping mechanism, the motion platform and the laser welding head for controlling the entire welding process;

[0016] The motion platform comprises:

[0017] An X-direction module for driving the laser welding head to move along the axial direction of the pipe (weld length direction);

[0018] A Y-direction module is installed on the mover of the X-direction module for driving the laser welding head to move along the direction perpendicular to the axial direction of the pipe (weld transverse direction or height direction);

[0019] The intelligent control system comprises:

[0020] A controller as a core processing unit;

[0021] A weld tracking sensor is installed in front of the laser welding head for real-time acquisition of weld images;

[0022] A molten pool monitoring sensor is installed behind the side of the laser welding head for real-time monitoring of the weld pool area;

[0023] A deformation detection sensor is installed on the frame and directed to the vicinity of the pipe welding area for detecting the deformation of the pipe during welding.

[0024] A human-computer interaction interface and a data management module; the human-computer interaction interface is used for parameter setting, state monitoring and alarm display; the data management module is used for storing welding process data, process parameter history and quality report, supporting data export and process analysis.

[0025] Preferably, the X-direction module comprises a servo motor, a synchronous belt transmission system, a linear guide rail and a position feedback device; the servo motor is fixed to the base of the X-direction module through a motor base, and the output shaft of the servo motor is provided with a driving synchronous pulley; a driven synchronous pulley is arranged at the other end of the X-direction module; a closed synchronous belt is connected to the driving synchronous pulley and the driven synchronous pulley, and is fixed to the mounting bottom plate of the Y-direction module; the linear guide rail is arranged parallel to the synchronous belt, and a sliding block is connected to the mounting bottom plate; the position feedback device is a grating ruler or a magnetic grating ruler, and a reading head is arranged on the mounting bottom plate, and a ruler body is arranged along the axial direction of the X-direction module, so as to provide high-precision position feedback.

[0026] Preferably, the transmission mode of the X-direction module is not limited to the synchronous belt transmission, and a ball screw transmission or a linear motor direct drive can also be used; when the ball screw transmission is used, the servo motor drives the ball screw to rotate through a shaft coupling, and drives the nut and the mounting bottom plate to move linearly; when the linear motor direct drive is used, the stator is fixed to the base of the X-direction module, and the rotor is directly connected to the mounting bottom plate.

[0027] Preferably, the weld seam tracking sensor is a high-speed linear array CCD camera, which is matched with a coaxial or paraxial structured light laser to form an active vision sensing system; the molten pool monitoring sensor is a high-speed infrared thermal imager or a high-speed CMOS camera equipped with a narrow-band filter, and the spectral response range covers the characteristic waveband of the molten pool radiation; the deformation detection sensor is a laser displacement sensor or a laser range finder.

[0028] Preferably, the controller is configured to perform the following steps:

[0029] S1: system initialization and calibration, establishing a unified mechanical coordinate system, image coordinate system and time reference, calibrating each sensor and presetting welding quality threshold, adjusting parameters and time parameters;

[0030] S2: real-time multi-sensor data acquisition and feature extraction, periodically and synchronously acquiring weld seam position deviation, molten pool stability index and pipe deformation compensation amount;

[0031] S3: welding quality coefficient fusion calculation, based on the features extracted in step S2, the real-time welding quality coefficient Q is calculated through weighted fusion;

[0032] S4: hierarchical residence and decision, when Q continuously falls below the preset threshold and reaches the shortest residence duration, it is determined that intervention is needed, and a control instruction containing the adjustment direction and the adjustment amount is generated;

[0033] S5: adaptive execution and recording, one or more of the laser power, the welding speed (X-direction speed) and the laser focal point position (Y-direction position) are adjusted according to the control instruction, and the whole process data is recorded to the non-volatile memory.

[0034] Compared with the prior art, the intelligent high-speed laser welding device for straight seam welded pipes has the following beneficial effects:

[0035] 1. Intelligent closed-loop control is realized: through the three-dimensional perception fusion of weld seam vision, molten pool infrared and deformation laser, and based on the comprehensive criterion of welding quality coefficient, real-time, closed-loop and self-adaptive adjustment of welding track and process parameters is realized, which fundamentally changes the open-loop mode of traditional welding relying on preset parameters.

[0036] 2. Quality stability is significantly improved: the intelligent decision mechanism of "threshold + shortest residence time" can effectively filter out transient interference, and only trigger precise quantitative adjustment when confirming abnormality persistence, avoiding misoperation and oscillation, and ensuring the high consistency of weld formation and penetration depth in high-speed welding process.

[0037] 3. Dynamic disturbance compensation capability: not only can the welding seam tracking deviation be corrected in real time, but also the core parameters such as laser power and welding speed can be dynamically optimized according to the molten pool state and workpiece deformation, and the influence caused by heat input accumulation, assembly micro-change or material difference can be adaptively compensated, which widens the process window.

[0038] 4. Establishing a full data traceability chain: the system records all sensor data, process parameters, intervention events and quality coefficients throughout the process at high frequency, forming a data chain that can be finely reviewed, providing a solid data foundation for root cause analysis of quality problems, iterative optimization of process parameters and predictive maintenance of equipment. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 The overall structure schematic diagram of the intelligent high-speed laser welding device for straight seam welded pipes is provided.

[0040] Figure 2 The clamping mechanism structure schematic diagram of the intelligent high-speed laser welding device for straight seam welded pipes is provided.

[0041] Figure 3 The motion platform structure schematic diagram of the intelligent high-speed laser welding device for straight seam welded pipes is provided.

[0042] Figure 4 The control method flow chart of the intelligent high-speed laser welding device for straight seam welded pipes is provided.

[0043] In the figure: 101, rack; 102, clamping mechanism; 103, movement platform; 104, laser welding head; 1021, fixed arc-shaped clamping plate; 1022, movable arc-shaped clamping plate; 1023, hydraulic cylinder one; 1031, X direction module; 1032, Y direction module; 10310, base; 10311, servo motor; 10312a, driving synchronous wheel; 10312b, driven synchronous wheel; 10312c, synchronous belt; 10313, linear guide rail; 1033, mounting bottom plate; 10321, hydraulic cylinder two; 10322, guiding mechanism. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments.

[0045] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0046] Embodiment 1: refer to Figures 1-3 The intelligent high-speed laser welding device for straight seam welded pipes of the present application mainly consists of a rack 101, a clamping mechanism 102, a movement platform 103, a laser welding head 104 and an intelligent control system.

[0047] The rack 101 is built by welding steel structure or heavy aluminum profile, which has sufficient rigidity and stability to absorb the vibration in the welding process.

[0048] The clamping mechanism 102 is fixed on the workbench surface of the rack 101 through a mounting seat, which includes a fixed arc-shaped clamping plate 1021 and a movable arc-shaped clamping plate 1022, the inner arc surfaces of the two are lined with soft pads made of copper or high-temperature-resistant engineering plastics to prevent scratching the pipe and increase the friction force, the back surface of the movable arc-shaped clamping plate 1022 is rigidly connected with the end of the piston rod of a hydraulic cylinder one 1023 through a flange, the cylinder body of the hydraulic cylinder one 1023 is fixed on the rack 101, the extension and retraction of the hydraulic cylinder one 1023 is controlled through a hydraulic system, so as to drive the movable arc-shaped clamping plate 1022 to approach or move away from the fixed arc-shaped clamping plate 1021, thereby realizing the clamping and releasing of the pipe, the clamping force can be accurately adjusted through the pressure of the hydraulic system to adapt to the clamping requirements of pipes with different wall thicknesses and avoid deformation caused by over-clamping.

[0049] The motion platform 103 is composed of an X-direction module 1031 and a Y-direction module 1032, and is horizontally arranged above the clamping mechanism 102 through a vertical column. The core function of the motion platform 103 is to drive the laser welding head 104 to realize precise movement in the axial direction (X-direction) and the vertical direction (Y-direction) of the pipe.

[0050] The specific structure of the X-direction module 1031 (see Figure 3 ) is as follows:

[0051] The X-direction module 1031 adopts a linear motion unit with high dynamic response. In this embodiment, the synchronous belt transmission mode is taken as an example for detailed description. The base 10310 of the X-direction module 1031 is fixed on the support frame of the motion platform 103 through bolts. The servo motor 10311 is installed on one end of the base 10310 through a motor seat. The output shaft of the servo motor 10311 is connected to the driving synchronous wheel 10312a through a key. The driven synchronous wheel 10312b is installed on the other end of the base 10310 through a bearing seat. A high-strength and low-stretch synchronous belt 10312c is wound around the driving and driven synchronous wheels. One side (usually the working surface) of the synchronous belt 10312c is fixedly connected to the installation bottom plate 1033 of the Y-direction module 1032 through a pressing plate. Two high-precision linear guides 10313 are installed in parallel to the direction of the synchronous belt 10312c. The guide part of the linear guide 10313 is fixed on the base 10310, and the sliding block part is connected to the installation bottom plate 1033 to bear the lateral torque and ensure the stability of the movement. In order to obtain the high-precision position feedback required for closed-loop control, the scale body of the grating ruler is installed on the base 10310, and the reading head is installed on the installation bottom plate 1033 to detect the absolute position of the installation bottom plate 1033 (i.e. the laser welding head 104) in the X-direction in real time. The servo motor 10311 receives the pulse or analog command from the controller to drive the synchronous wheel to rotate, and then pulls the installation bottom plate 1033 to move along the linear guide 10313 at high speed and high precision.

[0052] The synchronous belt transmission mode has the advantages of high speed, low noise and moderate cost. It should be understood that the structure of the X-direction module 1031 is not limited to this. In another embodiment, a ball screw transmission can be used instead of the synchronous belt transmission. The servo motor 10311 directly drives the ball screw to rotate through a shaft coupling. The nut matched with the ball screw is connected to the installation bottom plate 1033 through a nut seat. The rotation of the ball screw is converted into the linear motion of the nut and the installation bottom plate 1033. This mode has higher precision and better rigidity, but the maximum speed may be lower than that of the synchronous belt. In higher-end applications, a linear motor can be used for direct driving. The stator (primary) of the linear motor is fixed along the X-direction on the base 10310, and the rotor (secondary) is directly connected to the installation bottom plate 1033 to realize direct driving without intermediate transmission links, which has extremely high speed, acceleration and response performance.

[0053] The Y-direction module 1032 is as follows:

[0054] Y direction module 1032 is installed on the mounting base plate 1033 of the X direction module 1031 as a whole, and its core driving element is hydraulic cylinder two 10321, the cylinder body of which is fixed on the mounting base plate 1033, and the piston rod extends vertically downward, and the distal end is connected with the mounting bracket of the laser welding head 104 through a connecting piece. In order to ensure the straightness and anti-torsion ability of the laser welding head 104 in the vertical direction, a guide mechanism 10322 is arranged, such as a pair of parallel linear bearings and optical shafts, or a group of cross roller guide rails. The hydraulic cylinder two 10321 is controlled by an electro-hydraulic servo valve or a proportional valve in the intelligent control system, and can realize rapid and accurate displacement adjustment, which is mainly used for adjusting the position of the laser focal point relative to the surface of the workpiece (defocusing amount) according to the instruction, and correcting the position deviation in the transverse direction (relative to the weld) quickly during weld tracking.

[0055] The laser welding head 104 is installed at the end of the Y direction module 1032 through a quick-change interface, and its interior contains optical and gas path components such as a collimating mirror, a focusing mirror, and a protective gas nozzle, which is connected with an external high-power laser through an optical fiber.

[0056] The hardware core of the intelligent control system is an industrial multi-core processor or a programmable automation controller (PAC), which has powerful real-time data processing and motion control capabilities; the weld tracking sensor is preferably a high-speed linear array CCD camera, which is integrated with a linear laser in a shell to form a laser vision sensor. The sensor is installed in front of the laser welding head 104 at a certain forward inclination angle, so that its field of view can cover a certain weld area in front of the welding torch. The laser line is projected on the weld bevel, and the camera captures the deformed laser stripe image; the molten pool monitoring sensor is preferably a high-speed near-infrared thermal imager, which is installed at the side and rear of the laser welding head 104 to observe the molten pool and the heat affected zone at the best viewing angle; the deformation detection sensor is a high-precision laser displacement sensor, which is installed on the rack 101 and does not move with the motion platform 103. Its laser beam points to a fixed reference point near the starting point of the pipe welding, which is used to monitor the height change of the point during the welding process; the human-machine interface (HMI) is a touch screen, which is used for parameter setting, state monitoring, alarm display and manual operation; the data storage module is a non-volatile memory, which is used to store all process data. The controller communicates with the servo motor 10311 driver, hydraulic servo valve group, laser power supply and various sensors at high speed through field bus (such as EtherCAT) or analog / digital IO, to form a centralized control real-time system.

[0057] In embodiment 2, the intelligent control method executed by the controller is described in detail. The method is a real-time closed-loop process running periodically, and the overall process is as shown in Figure 4 .

[0058] Step S1: system initialization and calibration

[0059] This step should be performed first when the device is powered on or a new welding task is started.

[0060] 1. Mechanical zeroing and coordinate system establishment: Control the X-axis module 1031 and Y-axis module 1032 to move to the mechanical zero point, thereby establishing a unified machine tool coordinate system O. m -X m Y m The theoretical centerline of the pipe fitting weld is set as X. m The axis, vertically upward is Y m Positive direction of the axis.

[0061] 2. Sensor calibration:

[0062] Weld seam tracking sensor calibration: Manual and eye calibration is performed without pipe fittings or standard test blocks. The motion platform 103 is controlled to project a laser line onto a series of feature points with known spatial coordinates. Images are acquired, and the center pixel coordinates of the laser line are extracted. The least squares method is used to solve for the image pixel coordinates (u, v) to the machine coordinates (X). m Y m The transformation matrix M cam Simultaneously, the equations of the laser plane in the machine tool coordinate system are calibrated.

[0063] Molten pool monitoring sensor calibration: Using a standard blackbody radiation source, collect grayscale values ​​output by the thermal imager at different temperatures, establish a temperature-grayscale lookup table (LUT), complete the temperature calibration, and calibrate the relationship between its optical center and the machine tool coordinate system.

[0064] Deformation detection sensor calibration: When the pipe fitting is clamped in place but not yet welded, record the initial height value H measured by the laser displacement sensor. ref As a benchmark.

[0065] 3. Thresholds and Parameter Presets: Load or have the operator set a set of process parameters, including:

[0066] Quality threshold: Welding quality coefficient pass threshold Q th (e.g., 0.85), the threshold Q that triggers regulation alarm (e.g., 0.75).

[0067] Characteristic extreme value: Maximum permissible lateral deviation D max (e.g., 0.5mm), maximum permissible dynamic deformation C max (e.g., 1.0mm).

[0068] Weighting coefficients: w1, w2, w3 (e.g., set to 0.5, 0.3, 0.2 respectively).

[0069] Time parameter: Control period Ts (e.g., 5ms), used to determine the "shortest dwell time" T for state persistence. dwell (e.g., 100ms), the "safe clear duration" T after instruction latching. clear (e.g., 500ms).

[0070] Adjustment parameters: laser power reference value P0, welding speed reference value V0, focal position reference value Z0, and the mapping coefficient and upper limit value of each adjustment amount.

[0071] Step S2: Real-time multi-sensor data acquisition and feature extraction

[0072] 1. The system synchronously executes the following data acquisition and calculation tasks at a fixed control cycle Ts:

[0073] Calculation of weld position deviation D(k) (k is the index of the current cycle):

[0074] Acquire images from the weld seam tracking sensor; preprocess the images (filtering, binarization);

[0075] Extract the left and right edge point sets of the laser stripe at the weld bevel; calculate the line connecting the midpoints of the left and right edges, which represents the actual weld centerline in the image; use the calibration matrix Mcam to transform the weld centerline in the image to the machine coordinate system Y. m Position of direction Y act (k); The theoretical centerline of the weld is Y in the machine tool coordinate system. theory =0 (assuming perfect alignment); then the current position deviation is: D(k) > 0 indicates that the weld is biased to the right, and D(k) < 0 indicates that the weld is biased to the left.

[0076] 2. Molten pool temperature stability index S T (k) Calculation:

[0077] Acquire thermal images from the molten pool monitoring sensor, and extract the temperature values ​​T of all pixels within the preset region of interest (ROI, which typically covers the molten pool and part of the heat-affected zone). ij ;

[0078] Calculate the average temperature within the ROI: ;

[0079] Calculate the standard deviation of temperature within the ROI: ;

[0080] Define the molten pool temperature stability index: When the temperature distribution is very uniform, σ T Small, S T σ approaches 1; when the temperature distribution is uneven, resulting in localized overheating or undercooling, σ TIncrease, S T Decrease.

[0081] 3. Pipe deformation compensation amount C(k) calculation:

[0082] Read the current measurement value H of the deformation detection sensor current (k), calculate the deformation amount relative to the initial reference: ; C(k)>0 indicates that the point is bulging upwards, and C(k)<0 indicates that it is sinking downwards.

[0083] Step S3: Welding quality coefficient Q(k) fusion calculation

[0084] Based on the three feature quantities extracted in step S2, the comprehensive welding quality coefficient of the current period is calculated:

[0085]

[0086] The Q(k) value calculated by this formula is theoretically within the interval [0, 1], and the closer to 1 indicates the better the comprehensive state of the welding process.

[0087] Step S4: Hierarchical residence and decision

[0088] This step determines whether intervention is needed and how to intervene.

[0089] 1. State evaluation and residence count: The system maintains a "low quality state" counter Counter lowQ If Q(k)<Q alarm , then Counter lowQ =Counter lowQ +1; if Q(k)≥Q alarm , then Counter lowQ =0; only when Counter lowQ ·Ts≥T dwell , that is, the low quality state lasts more than the preset minimum residence time, the system confirms the need to generate control instructions, which effectively avoids false actions caused by transient disturbances (such as spatter blocking the sensor).

[0090] 2. Control instruction generation: When it is confirmed that intervention is needed, an instruction containing the adjustment direction and adjustment amount is generated.

[0091] Adjustment direction determination: mainly determined by the deviation D(k). If D(k)>δ (δ is a dead zone, such as 0.05mm), it is determined that correction is needed in the -Y direction (to the left); if −D(k)<−δ, it is determined that correction is needed in the +Y direction (to the right), which is achieved by fine-tuning the position of the Y direction module 1032.

[0092] Adjustment amount calculation:

[0093] a. Y-direction position adjustment amount ΔY: proportional control, ΔY = -K p · D(k), where K p is a proportional coefficient, and a maximum step limit is imposed on ΔY.

[0094] b. Laser power adjustment amount ΔP and welding speed adjustment amount ΔV: These adjustments are mainly used to improve the molten pool stability S T and to cope with changes in heat input requirements that may be caused by deformation C(k). The adjustment amount is determined based on the magnitude ΔQ = Q alarm - Q(k) and the value of S alarm (k) that Q(k) is below Q T . For example, a set of rules is defined:

[0095] If S T (k) < S T_th and ΔQ is large, mainly increase the laser power ΔP (positive value) and slightly reduce the welding speed ΔV (negative value) to enhance the penetration and stabilize the molten pool; if |C(k)| increases significantly and ΔQ is mainly contributed by the deformation term, fine-tune the defocusing amount (through the Y direction) or the power to compensate for heat loss or concentrate energy.

[0096] c. All calculated adjustment amounts ΔY, ΔP, ΔV need to be subjected to amplitude limiting to ensure that they are within the safe and process-allowed range of the equipment.

[0097] 3. Instruction latching: Once the adjustment instruction is issued, the system enters the "instruction latching" state, and within the next T clear duration, even if Q(k) is still below Q alarm , no new instruction is generated, but the adjustment effect is continuously observed, which prevents the system from oscillating within the response time.

[0098] Step S5: Adaptive execution and recording

[0099] 1. Instruction execution: the controller sends the generated adjustment instruction to each actuator:

[0100] Send a new position instruction to the servo driver ; send a new power setting value to the laser power supply ; control the electro-hydraulic servo valve to drive the hydraulic cylinder 10321 to the new Y cmd position.

[0101] 2. Process monitoring and reset: During instruction latching, Q(k) is continuously monitored, and if Q(k) returns to Q clear within the safe clearing duration T alarm and remains for a period of time, it is considered that the adjustment is effective, and the system clears the CounterlowQ , exit the latching state, and the current intervention event ends; if T clear If Q(k) has not recovered after the intervention, a higher level of alarm (such as a shutdown inspection) can be triggered, and it is recorded as an intervention failure event.

[0102] 3. Data recording: During the entire welding process, whether an intervention occurs or not, the system records the data of time stamp t, D(k), S T (k), C(k), Q(k), laser power P, welding speed V, focal position Z, etc. at high frequency (such as once every 10 cycles), and when an intervention event occurs, it additionally records the event trigger time, duration, adjustment instructions (ΔY, ΔP, ΔV) taken, and key parameter values before and after adjustment, etc. All data are packaged and stored in the data storage module, and can be exported through the human-computer interaction interface, for production quality report and process deep analysis.

[0103] Through the cyclic execution of the above five steps, the device of the present application realizes real-time perception, intelligent evaluation, self-adaptive adjustment and full-process digital traceability of the laser welding process of straight seam welded pipes, and significantly improves the stability of welding quality and the intelligent level of the production process.

[0104] The above is only the preferred specific implementation of the present application, but the protection scope of the present application is not limited thereto, any skilled person in the art, according to the technical solution and the inventive concept of the present application, makes equivalent replacement or change within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. An intelligent high speed laser welding apparatus for straight seam welded pipe, characterized by, The utility model relates to a kind of laser welding device, including: Rack, the carrying body of device; Clamping mechanism, installed on rack, for fixed pipe fittings to be welded, it includes a pair of oppositely arranged arc clamping plate, one is fixed arc clamping plate, the other is movable arc clamping plate, the movable arc clamping plate is connected to the piston rod end of hydraulic cylinder one, is driven to realize clamping and loosening by hydraulic cylinder one; Motion platform, installed on rack and located above clamping mechanism, for driving welding executor to carry out two-dimensional motion; Laser welding head, as welding executor, is installed at the motion end of motion platform, for emitting laser beam; Intelligent control system, electrically connected with clamping mechanism, motion platform and laser welding head, for controlling whole welding process; The motion platform includes: X direction module, for driving laser welding head to move along the axial direction of pipe fittings; Y direction module, installed on the mover of X direction module, for driving laser welding head to move along the direction perpendicular to the axial direction of pipe fittings; The intelligent control system includes: Controller, as core processing unit; Weld seam tracking sensor, for real-time acquisition of weld seam image; Melt pool monitoring sensor, for real-time monitoring of welding pool area; Deformation detection sensor, for detecting the deformation of pipe fittings during welding process.

2. The intelligent high speed laser welding of straight seam welded pipe apparatus as claimed in claim 1 wherein: The X direction module includes servo motor, synchronous belt transmission system, linear guide rail and position feedback device;The servo motor is fixed to the base of X direction module through motor base, and the output shaft is installed with driving synchronous wheel;Driven synchronous wheel is installed at the other end of X direction module;Closed synchronous belt connects driving and driven wheels, and is fixed with Y direction module mounting bottom plate;The linear guide rail is arranged parallel to the synchronous belt, and the slider is connected with the mounting bottom plate;The position feedback device is grating ruler or magnetic grating ruler, and the reading head is installed on the mounting bottom plate, and the ruler body is laid along the axial direction of X direction module.

3. The apparatus for intelligent high speed laser welding of straight seam welded pipes as claimed in claim 2 wherein: When the transmission mode of X direction module adopts ball screw transmission, the servo motor drives the ball screw to rotate through coupling, and drives the nut and mounting bottom plate to move linearly;When direct drive is adopted, the stator is fixed to the base of X direction module, and the mover is directly connected with the mounting bottom plate.

4. The apparatus for intelligent high speed laser welding of straight seam welded pipes as claimed in claim 1 wherein: The weld seam tracking sensor is high-speed linear array CCD camera;The melt pool monitoring sensor is high-speed infrared thermal imager or high-speed CMOS camera equipped with narrow-band filter;The deformation detection sensor is laser displacement sensor or laser range finder.

5. The apparatus for intelligent high speed laser welding of straight seam welded pipes as claimed in claim 1 wherein: The controller is configured to execute the following steps: S1: system initialization and calibration, establish unified mechanical coordinate system, image coordinate system and time reference, calibrate each sensor and preset welding quality threshold, adjustment parameter and time parameter; S2: real-time multi-sensor data acquisition and feature extraction, periodically and synchronously acquire weld seam position deviation, melt pool stability index and pipe fitting deformation compensation amount; S3: welding quality coefficient fusion calculation, based on the features extracted in step S2, calculate real-time welding quality coefficient Q by weighted fusion; S4: hierarchical residence and decision, when Q continuously lower than preset threshold and reach the shortest residence duration, judge that intervention is needed, and generate control instruction containing adjustment direction and adjustment amount. S5: adaptive execution and record, according to the control instruction to adjust one or more of the laser power, welding speed, laser focal position, and record the whole process data to the non-volatile memory.

6. The apparatus for intelligent high speed laser welding of straight seam welded pipes as claimed in claim 5 wherein: In step S3, the calculation formula of the welding quality coefficient Q is: wherein D is the transverse deviation of the weld position measured by the weld tracking sensor, is a deviation normalization function, D max is the maximum allowable deviation; S T is a pool monitoring sensor calculated pool temperature stability index, the value of which is closer to 1 indicates more stable; C is the pipe height direction deformation variable measured by the deformation detection sensor, is a deformation normalization function, C max is the maximum allowable deformation; w1, w2, w3 are weight coefficients, and w1+w2+w3=1.

7. The apparatus for intelligent high speed laser welding of straight seam welded pipes as claimed in claim 6 wherein: The molten bath temperature stability index S T The calculation method is: in the attention area defined by the molten bath monitoring sensor, the standard deviation σ T of the temperature distribution is calculated, and the ratio of the standard deviation σ to the average temperature T, that is, 8. The intelligent high speed laser welding of straight seam welded pipe apparatus as claimed in claim 5 wherein: In step S4, the generating the control instruction specifically comprises: determining the adjustment direction of the Y direction module according to the positive and negative of the weld position deviation D, calculating one or more of the laser power adjustment amount ΔP and the welding speed adjustment amount ΔV through a preset mapping relationship according to the amplitude ΔQ of Q being lower than the threshold value and the degree of decline of the molten pool stability index S T .

9. The apparatus for intelligent high speed laser welding of straight seam welded pipes as claimed in claim 8 wherein: After the control instruction is sent, the system enters a latch-up state, in which no new control instruction is repeatedly generated until an adjustment completion signal is received or a safety clearance time length is reached; the adjustment completion signal is triggered when the welding quality coefficient Q rises back to above the threshold and is maintained for a period of time.

10. The apparatus for intelligent high speed laser welding of straight seam welded pipes as claimed in claim 1 wherein: It also includes a human-computer interaction interface and a data management module; the human-computer interaction interface is used for parameter setting, state monitoring and alarm display; the data management module is used for storing welding process data, process parameter history and quality report, supporting data export and process analysis.

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