PLC-Based Automatic Surfacing Method, System and Storage Medium for RTJ Grooves

Abstract

The present application discloses an automatic surfacing method for RTJ grooves based on PLC, which relates to the technical field of automatic surfacing. It includes establishing a groove body reference coordinate system to generate an initial welding path; obtaining the three-dimensional spatial relationship between the top width parameter and the tilt angle parameter, and generating dynamic welding path data to obtain the welding path; obtaining the interlayer temperature distribution data in the groove body in real time to generate an interlayer temperature gradient parameter; collecting the molten pool arc voltage fluctuation data and the droplet transfer frequency characteristics in real time to correct the three-dimensional coordinate offset of the welding torch; performing stepped surfacing control according to the preset surfacing stratification strategy to compensate for the tilt angle of the welding torch; obtaining the molten pool coverage width and adjusting the welding travel speed; obtaining the cumulative welding layer number characteristic value during welding and executing a lane change welding instruction until the preset groove body termination height reference value is reached. The present application has the effect of improving the stability and flexibility during welding.

Description

Technical Field

[0001] This application relates to the technical field of automatic surfacing, and particularly to an automatic surfacing method, system and storage medium for RTJ grooves based on PLC. Background Art

[0002] The technology of metal seal groove surfacing has important applications in the fields of nuclear power equipment, pressure vessels, etc. The core lies in forming a dense seal structure through multi-layer surfacing. Traditional methods rely on the experience of operators for path planning and parameter setting.

[0003] In the prior art, it is difficult to accurately match the geometric features of the groove when manually setting the welding path, resulting in uneven interlayer lap and prone to defects such as pores and lack of fusion. Secondly, existing automated equipment mostly uses fixed-program control and lacks real-time feedback adjustment of the dynamic characteristics of the molten pool. When the groove inclination changes or thermal deformation occurs, bead offset and cladding layer thickness fluctuation are likely to occur. In addition, in current partial technologies, geometric parameter acquisition, path planning, and process control are fragmented into independent modules, lacking an intelligent decision-making system for parameter linkage, resulting in insufficient welding quality stability and a long-term low qualification rate for surfacing of complex grooves. Summary of the Invention

[0004] The purpose of the present invention is to provide an automatic surfacing method, system and storage medium for RTJ grooves based on PLC to solve the problems raised in the above background art.

[0005] In a first aspect, this application provides an automatic surfacing method for RTJ grooves based on PLC, and the method includes:

[0006] Establish a reference coordinate system for the groove and obtain the top width parameter and tilt angle parameter, and generate an initial welding path according to the geometric relationship between the top width parameter and the tilt angle parameter;

[0007] Obtain the three-dimensional spatial relationship between the top width parameter and the tilt angle parameter, establish a multi-layer welding trajectory model based on the three-dimensional spatial relationship and generate dynamic welding path data including interlayer trajectory offset, and obtain the welding path by combining the dynamic welding path data and the initial welding path;

[0008] Real-time obtain the interlayer temperature distribution data in the groove, and generate an interlayer temperature gradient parameter by combining the interlayer temperature distribution data and the interlayer trajectory offset;

[0009] Real-time collect the molten pool arc voltage fluctuation data and the droplet transfer frequency characteristics, and correct the three-dimensional coordinate offset of the welding torch by combining the arc voltage fluctuation data, the droplet transfer frequency characteristics and the interlayer temperature gradient parameter;

[0010] Execute stepped surfacing control according to the preset surfacing stratification strategy. After completing the bottom layer of continuous welding, activate the sidewall staggered welding mode and generate inclination compensation control parameters, and perform inclination compensation on the welding torch according to the inclination compensation control parameters;

[0011] Obtain the molten pool coverage width, extract the correlation between the interlayer temperature gradient parameter and the molten pool coverage width, and adjust the welding travel speed based on the correlation to maintain a preset fusion area ratio between the constant clad layer thickness and the molten pool coverage width;

[0012] Obtain the characteristic value of the cumulative number of welding layers during welding, perform dynamic matching according to the characteristic value of the cumulative number of welding layers and the preset groove depth determination threshold to obtain a matching result, and execute a lane-changing welding instruction according to the matching result until the preset groove termination height reference value is reached.

[0013] Preferably, the step of generating the initial welding path according to the geometric relationship between the top width parameter and the tilt angle parameter is specifically as follows:

[0014] Perform three-dimensional contour scanning on the top width parameter of the groove to obtain the measurement data of the top width parameter, and collect the real-time data of the tilt angle parameter;

[0015] Select the starting point coordinates and the ending point coordinates in the groove reference coordinate system according to the measurement data and the real-time data;

[0016] Perform route planning according to the starting point coordinates and the ending point coordinates to generate a planned path, obtain the path curvature characteristic value according to the planned path, and combine the starting point coordinates, the ending point coordinates and the path curvature characteristic value to obtain an initial path data set;

[0017] Obtain the geometric shape parameters of the welding torch end, and perform equidistant offset processing on the initial path data set according to the geometric shape parameters to obtain a target data set;

[0018] Obtain the spatial coordinate sequence of the corrected welding center line according to the target data set, and generate an initial welding path according to the spatial coordinate sequence.

[0019] Preferably, the step of establishing a multi-layer welding trajectory model based on the three-dimensional spatial relationship and generating dynamic welding path data including interlayer trajectory offset amounts is specifically as follows:

[0020] Extract data from the target data set to obtain the interlayer trajectory offset parameter in the initial welding path;

[0021] Obtain the welding layer number, increment the interlayer trajectory offset according to the welding layer number to generate an arithmetic sequence;

[0022] Obtain the coefficient of thermal expansion of the material and the temperature of the current layer, and generate a thermal deformation compensation amount according to the coefficient of thermal expansion and the temperature of the current layer;

[0023] Compensate the interlayer trajectory offset parameter according to the thermal deformation compensation amount and the arithmetic sequence to obtain a target offset parameter, and construct a multi-layer welding trajectory model according to the target offset parameter;

[0024] According to the multi-layer welding trajectory model, obtain a control instruction set for the layer height control threshold and the interlayer overlap rate, and obtain dynamic welding path data based on the instruction set.

[0025] Preferably, the step of correcting the three-dimensional coordinate offset of the welding torch is specifically as follows:

[0026] Based on the arc voltage fluctuation data, obtain the real-time waveform data of the arc voltage, and perform multi-scale decomposition on the real-time waveform data to obtain a voltage fluctuation feature vector;

[0027] Based on the droplet transfer frequency characteristics, obtain the sequential image data during the droplet transfer process, obtain the standard deviation of the time interval between the formation of adjacent droplets according to the sequential image data, and obtain a transfer stability index according to the standard deviation;

[0028] Input the voltage fluctuation feature vector and the transfer stability index into a preset prediction model to obtain a lateral offset compensation amount of the welding torch;

[0029] Input the lateral offset compensation amount into the spatial coordinate register of the welding torch to correct the three-dimensional coordinate offset of the welding torch.

[0030] Preferably, the step of performing stepped surfacing control according to a preset surfacing layer strategy is specifically as follows:

[0031] Based on the preset surfacing layer strategy, disassemble the surfacing layer strategy to obtain the total depth of multiple grooves;

[0032] Arrange the total depth of the grooves to obtain a depth sequence rule, and obtain a layer thickness threshold parameter according to the depth sequence rule;

[0033] Obtain the current welding layer number, obtain the preset swing amplitude parameter corresponding to the current layer number according to the current welding layer number, and obtain an interlayer swing frequency compensation coefficient according to the swing amplitude parameter and the layer thickness threshold parameter;

[0034] Generate an acceleration control signal for the periodic swing trajectory of the welding torch according to the interlayer swing frequency compensation coefficient;

[0035] When the welding torch triggers the acceleration control signal during interlayer transition, an inclination compensation parameter is generated according to the layer thickness threshold parameter, and the welding torch is controlled to perform sidewall welding according to the inclination compensation parameter.

[0036] Preferably, the step of obtaining the molten pool coverage width, extracting the correlation between the interlayer temperature gradient parameter and the molten pool coverage width, and adjusting the welding travel speed based on the correlation is specifically as follows:

[0037] Based on the path curvature eigenvalue, the path curvature is monitored in real time to obtain the tangent angle difference between adjacent path points, and a path curvature change parameter is obtained based on the tangent angle difference;

[0038] Obtain the current travel speed of the welding torch, establish a quantization relationship model based on the curvature change parameter and the current travel speed, and generate a travel speed adjustment coefficient according to the quantization relationship model;

[0039] Obtain the molten pool coverage width, and extract the correlation between the interlayer temperature gradient parameter and the molten pool coverage width;

[0040] Obtain the pulse frequency output value of the servo motor according to the travel speed adjustment coefficient and the correlation, and adjust the welding travel speed according to the pulse frequency output value.

[0041] Preferably, the step of dynamically matching the cumulative welding layer number eigenvalue with a preset groove depth determination threshold to obtain a matching result and executing a lane change welding instruction according to the matching result is specifically as follows:

[0042] Based on the welding path, path nodes are set on the welding path. After the welding torch passes through the path nodes, the number of path points is counted to obtain a cumulative welding layer number eigenvalue;

[0043] Dynamically match the cumulative welding layer number eigenvalue with the preset groove depth determination threshold to obtain a matching result;

[0044] Obtain the weld width uniformity value and the interlayer fusion area of the current welding layer, and obtain a cladding quality evaluation parameter according to the weld width uniformity value and the interlayer fusion area;

[0045] Combining the matching result and the cladding quality evaluation parameter, obtain an optimized adjustment amount for the lane change distance, and generate a lane change path control data set with a smooth transition curve based on the optimized adjustment amount;

[0046] Generate a lane change welding instruction based on the lane change path control data set, and call the welding torch to perform a lane change operation according to the lane change welding instruction.

[0047] Second aspect, the present application provides an automatic surfacing system for RTJ grooves based on PLC, and the system includes:

[0048] Initial path generation module: used to establish a reference coordinate system for the groove body and obtain the top width parameter and the tilt angle parameter, and generate an initial welding path according to the geometric relationship between the top width parameter and the tilt angle parameter;

[0049] Path optimization module: used to obtain the three-dimensional spatial relationship between the top width parameter and the tilt angle parameter, establish a multi-layer welding trajectory model based on the three-dimensional spatial relationship and generate dynamic welding path data including the inter-layer trajectory offset, and obtain the welding path by combining the dynamic welding path data and the initial welding path;

[0050] Inter-layer temperature analysis module: used to obtain the inter-layer temperature distribution data in the groove body in real time, and generate an inter-layer temperature gradient parameter by combining the inter-layer temperature distribution data and the inter-layer trajectory offset;

[0051] Offset analysis module: used to collect the molten pool arc voltage fluctuation data and the droplet transfer frequency characteristics in real time, and correct the three-dimensional coordinate offset of the welding torch by combining the arc voltage fluctuation data, the droplet transfer frequency characteristics and the inter-layer temperature gradient parameter;

[0052] Welding torch compensation module: used to perform stepped surfacing control according to a preset surfacing stratification strategy, activate the side wall staggered welding mode after completing the bottom layer circular continuous welding and generate an inclination compensation control parameter, and perform inclination compensation on the welding torch according to the inclination compensation control parameter;

[0053] Speed adjustment module: used to obtain the molten pool coverage width, extract the correlation between the inter-layer temperature gradient parameter and the molten pool coverage width, and adjust the welding travel speed based on the correlation to maintain a preset fusion area ratio between the constant cladding layer thickness and the molten pool coverage width;

[0054] Welding torch lane change module: used to obtain the cumulative welding layer characteristic value during welding, perform dynamic matching according to the cumulative welding layer characteristic value and a preset groove depth determination threshold to obtain a matching result, and execute a lane change welding instruction according to the matching result until a preset groove termination height reference value is reached.

[0055] Third aspect, the present application provides a computer-readable storage medium for automatic surfacing of RTJ grooves based on PLC, and the computer-readable storage medium includes:

[0056] A computer program is stored on the computer-readable storage medium, and the computer program executes the automatic surfacing method for RTJ grooves based on PLC described in any one of the above when running on a processor.

[0057] In summary, the present application includes at least one of the following beneficial technical effects:

[0058] An initial welding path is generated based on the top width parameter and the tilt angle parameter of the groove body, and then dynamic welding path data is generated according to the established multi-layer welding trajectory model. The initial welding path is adjusted according to the dynamic welding path data to obtain the welding path. Temperature step data is obtained based on the interlayer temperature distribution data in the groove body, and data in the molten pool is further collected. The offset generated during the welding process of the welding torch is corrected according to the data therein. Then, the inclination compensation control parameter is obtained, and inclination compensation is performed when the welding torch performs side wall welding. Then, the welding travel speed during welding is adjusted according to the correlation between the interlayer temperature gradient parameter and the molten pool coverage width. Finally, the cumulative welding layer number characteristic value generated during welding is dynamically matched with the preset groove depth determination threshold, and then the lane change welding instruction is executed. The stability and flexibility during welding are improved. Description of the Drawings

[0059] Figure 1 is the step flow chart of the automatic surfacing method for RTJ grooves based on PLC provided by the embodiment of the present application;

[0060] Figure 2 is the module block diagram of the automatic surfacing system for RTJ grooves based on PLC provided by the embodiment of the present application.

[0061] Description of the reference numerals: 1. Initial path generation module; 2. Path optimization module; 3. Interlayer temperature analysis module; 4. Offset analysis module; 5. Welding torch compensation module; 6. Speed adjustment module; 7. Welding torch lane change module. Detailed Embodiments

[0062] The following further describes the present application in detail with reference to the attached Figure 1 - Figure 2 drawings, but the embodiments of the present invention are not limited thereto.

[0063] The embodiment of the present application discloses an automatic surfacing method, system and storage medium for RTJ grooves based on PLC.

[0064] In this embodiment, for the automatic surfacing method for RTJ grooves based on PLC, the method includes:

[0065] S100: Establish a groove body reference coordinate system and obtain the top width parameter and the tilt angle parameter, and generate an initial welding path according to the geometric relationship between the top width parameter and the tilt angle parameter;

[0066] S200: Obtain the three-dimensional spatial relationship between the top width parameter and the tilt angle parameter, establish a multi-layer welding trajectory model based on the three-dimensional spatial relationship, generate dynamic welding path data including the interlayer trajectory offset, and obtain the welding path by combining the dynamic welding path data and the initial welding path;

[0067] S300: Obtain the interlayer temperature distribution data in the tank in real time, and generate the interlayer temperature gradient parameter by combining the interlayer temperature distribution data and the interlayer trajectory offset;

[0068] S400: Collect the molten pool arc voltage fluctuation data and the droplet transfer frequency characteristics in real time, and correct the three-dimensional coordinate offset of the welding torch by combining the arc voltage fluctuation data, the droplet transfer frequency characteristics and the interlayer temperature gradient parameter;

[0069] S500: Execute the stepped surfacing control according to the preset surfacing stratification strategy, activate the sidewall staggered welding mode after completing the bottom layer circular continuous welding, generate the tilt angle compensation control parameter, and perform the tilt angle compensation on the welding torch according to the tilt angle compensation control parameter;

[0070] S600: Obtain the molten pool coverage width, extract the correlation between the interlayer temperature gradient parameter and the molten pool coverage width, and adjust the welding travel speed based on the correlation to maintain the preset fusion area ratio between the constant cladding layer thickness and the molten pool coverage width;

[0071] S700: Obtain the cumulative welding layer characteristic value during welding, perform dynamic matching according to the cumulative welding layer characteristic value and the preset tank depth determination threshold, obtain the matching result, and execute the lane-changing welding instruction according to the matching result until the preset tank termination height reference value is reached.

[0072] It should be noted that the above modules are only the basic steps of this embodiment. In the specific implementation process, on the premise of not affecting the overall implementation effect, some steps can be appropriately added, reduced or modified.

[0073] The steps of generating the initial welding path according to the geometric relationship between the top width parameter and the tilt angle parameter are specifically as follows:

[0074] Perform a three-dimensional contour scan on the top width parameter of the tank to obtain the measurement data of the top width parameter, and collect the real-time data of the tilt angle parameter;

[0075] Select the starting point coordinates and the ending point coordinates in the tank reference coordinate system according to the measurement data and the real-time data;

[0076] Perform route planning according to the starting point coordinates and the ending point coordinates to generate a planned path, obtain the path curvature characteristic value according to the planned path, and combine the starting point coordinates, the ending point coordinates and the path curvature characteristic value to obtain the initial path data set;

[0077] Obtain the geometric shape parameters of the end of the welding torch, and perform an equidistant offset process on the initial path dataset according to the geometric shape parameters to obtain the target dataset;

[0078] Obtain the spatial coordinate sequence of the corrected welding center line according to the target dataset, and generate the initial welding path according to the spatial coordinate sequence.

[0079] In application, taking the welding process of RTJ grooves in a certain factory as an example, scan an elliptical groove body, and measure that the top width parameter is 65 mm at the major axis and 45 mm at the minor axis, and the inclination angle parameter is 25°. Select the starting point (0, 0, 0) and the ending point (300, 0, 0) in the reference coordinate system, and plan the path curvature eigenvalue to be 0.05 / mm. The end of the welding torch is a nozzle with a cone angle of 60°. After the equidistant offset process, the target dataset is obtained, and the spatial coordinate sequence of the initial welding path is generated at an interval of 0.1 mm. During actual welding, the corrected welding center line is offset by +0.2 mm in the X direction and fluctuates within ±0.1 mm in the Y direction.

[0080] The steps of establishing a multi-layer welding trajectory model based on the three-dimensional spatial relationship and generating dynamic welding path data including the inter-layer trajectory offset amount are specifically as follows:

[0081] Extract data from the target dataset to obtain the inter-layer trajectory offset amount parameter in the initial welding path;

[0082] Obtain the welding layer number, increment the inter-layer trajectory offset amount according to the welding layer number, and generate an arithmetic sequence;

[0083] Obtain the material expansion coefficient and the current layer temperature, and generate a thermal deformation compensation amount according to the expansion coefficient and the current layer temperature;

[0084] Compensate the inter-layer trajectory offset amount parameter according to the thermal deformation compensation amount and the arithmetic sequence to obtain the target offset parameter, and construct a multi-layer welding trajectory model according to the target offset parameter;

[0085] According to the multi-layer welding trajectory model, obtain the layer height control threshold and the control instruction set for the inter-layer overlap rate, and obtain the dynamic welding path data based on the instruction set.

[0086] In application, taking the welding process of RTJ grooves in a certain factory as an example, when welding a stainless steel groove body, the initial inter-layer trajectory offset amount is set to 0.3 mm. Generate an arithmetic sequence by incrementing according to the welding layer number, and the offset amounts of the 1st - 5th layers are 0.3 / 0.8 / 1.3 / 1.8 / 2.3 mm respectively. The measured material expansion coefficient is 1.2×10^-5 / °C, and when the current layer temperature is 250°C, the thermal deformation compensation amount is calculated to be 0.15 mm. The final target offset parameter is adjusted to 0.45 mm, the layer height control threshold of the constructed 5-layer welding trajectory model is 2 mm, and the inter-layer overlap rate is set to 35%.

[0087] Steps to correct the three - dimensional coordinate offset of the welding torch, specifically:

[0088] Based on the arc voltage fluctuation data, obtain the real - time waveform data of the arc voltage, and perform multi - scale decomposition on the real - time waveform data to obtain the voltage fluctuation feature vector;

[0089] Based on the droplet transfer frequency characteristics, obtain the sequential image data during the droplet transfer process, obtain the standard deviation of the time interval between adjacent droplet formations according to the sequential image data, and obtain the transfer stability index according to the standard deviation;

[0090] Input the voltage fluctuation feature vector and the transfer stability index into a preset prediction model to obtain the lateral offset compensation amount of the welding torch;

[0091] Input the lateral offset compensation amount into the spatial coordinate register of the welding torch to correct the three - dimensional coordinate offset of the welding torch.

[0092] In application, taking the process of welding RTJ grooves in a certain factory as an example, during a certain welding process, the monitored arc voltage fluctuates between 25 - 28V. After multi - scale decomposition, the voltage fluctuation feature vector [0.5, 1.2, 0.8] is obtained. The analysis of the droplet transfer image shows that the standard deviation of the time interval is 0.15s, and the transfer stability index is 0.85. The prediction model outputs the lateral offset compensation amount X + 0.3mm / Y - 0.2mm. After updating the coordinate register of the welding torch, the three - dimensional coordinate offset is corrected from (0, 0, 0) to (0.3, - 0.2, 0).

[0093] Steps to perform stepped surfacing control according to a preset surfacing stratification strategy, specifically:

[0094] Based on the preset surfacing stratification strategy, disassemble the surfacing stratification strategy to obtain the total depths of multiple grooves;

[0095] Arrange the total depths of the grooves to obtain a depth sequence rule, and obtain the layer thickness threshold parameter according to the depth sequence rule;

[0096] Obtain the current welding layer number, obtain the preset swing amplitude parameter corresponding to the current layer number according to the current welding layer number, and obtain the inter - layer swing frequency compensation coefficient according to the swing amplitude parameter and the layer thickness threshold parameter;

[0097] Generate an acceleration control signal for the periodic swing trajectory of the welding torch according to the inter - layer swing frequency compensation coefficient;

[0098] When the welding torch triggers the acceleration control signal during inter - layer transition, generate an inclination compensation parameter according to the layer thickness threshold parameter, and control the welding torch to perform side - wall welding according to the inclination compensation parameter.

[0099] In operation, taking the process of welding an RTJ groove in a certain factory as an example, when a groove with a depth of 15 mm implements a layering strategy, the total depth is split into 5 layers with a thickness of 3 mm each. When welding the third layer, the swing amplitude parameter is set to ±1.5 mm, and a swing frequency compensation coefficient of 1.2 is generated in combination with the layer thickness threshold. The generated acceleration control signal is 0.5 g. After triggering, the welding torch automatically increases the inclination compensation by 10° when welding on the side wall to ensure that the penetration depth reaches 2.8 mm.

[0100] The steps of obtaining the molten pool coverage width, extracting the correlation between the interlayer temperature gradient parameter and the molten pool coverage width, and adjusting the welding travel speed based on the correlation are as follows:

[0101] Based on the path curvature eigenvalue, the path curvature is monitored in real time to obtain the tangent angle difference between adjacent path points, and the path curvature change parameter is obtained based on the tangent angle difference;

[0102] Obtain the current travel speed of the welding torch, establish a quantization relationship model based on the curvature change parameter and the current travel speed, and generate a travel speed adjustment coefficient according to the quantization relationship model;

[0103] Obtain the molten pool coverage width, and extract the correlation between the interlayer temperature gradient parameter and the molten pool coverage width;

[0104] Obtain the pulse frequency output value of the servo motor according to the travel speed adjustment coefficient and the correlation, and adjust the welding travel speed according to the pulse frequency output value.

[0105] In operation, taking the process of welding an RTJ groove in a certain factory as an example, when the tangent angle difference between adjacent path points of a groove with a curvature change is monitored to be 8°, and the curvature change parameter is 0.08 / mm. When the current travel speed is 200 mm / min, the quantization model outputs an adjustment coefficient of 0.9. Combining the correlation between the temperature gradient parameter of 12°C / mm and the molten pool width of 7.5 mm, the pulse frequency of the servo motor is adjusted from 2000 Hz to 1800 Hz, and the final travel speed is reduced to 180 mm / min.

[0106] The steps of dynamically matching the cumulative welding layer number eigenvalue with the preset groove depth determination threshold to obtain a matching result and executing a lane-changing welding instruction according to the matching result are as follows:

[0107] Based on the welding path, set path nodes on the welding path. After the welding torch passes through the path nodes, count the number of path points to obtain the cumulative welding layer number eigenvalue;

[0108] Dynamically match the cumulative welding layer number eigenvalue with the preset groove depth determination threshold to obtain a matching result;

[0109] Obtain the width uniformity value of the current welding layer and the interlayer fusion area, and obtain the cladding quality evaluation parameter according to the width uniformity value and the interlayer fusion area;

[0110] Combine the matching result and the cladding quality evaluation parameter to obtain the optimized adjustment amount of the lane-changing distance, and generate a lane-changing path control data set with a smooth transition curve based on the optimized adjustment amount;

[0111] Generate a lane-changing welding instruction based on the lane-changing path control data set, and call the welding torch to perform the lane-changing operation according to the lane-changing welding instruction.

[0112] In application, taking the process of welding an RTJ groove in a certain factory as an example, a certain annular groove body is provided with 36 path nodes, and the matching depth threshold is reached when the cumulative number of welding layers reaches 24 layers. The width uniformity value of the current layer is 0.95, the fusion area is 85 mm², and the evaluation parameter is excellent. The optimized adjustment amount of the lane-changing distance is generated as +0.2 mm. The lane-changing path control data set contains 3 Bezier curves, and the smooth transition radius is R5 mm. When executing the lane-changing instruction, the welding torch completes a 1.2 mm offset on the X-axis within 0.5 seconds.

[0113] The embodiment of the present invention provides an RTJ groove automatic surfacing system based on a PLC, which uses any one of the above-mentioned RTJ groove automatic surfacing methods based on a PLC. The system includes the following:

[0114] Initial path generation module 1: Used to establish a groove body reference coordinate system and obtain the top width parameter and the tilt angle parameter, and generate an initial welding path according to the geometric relationship between the top width parameter and the tilt angle parameter;

[0115] Path optimization module 2: Used to obtain the three-dimensional spatial relationship between the top width parameter and the tilt angle parameter, establish a multi-layer welding trajectory model based on the three-dimensional spatial relationship and generate dynamic welding path data including the interlayer trajectory offset amount, and combine the dynamic welding path data and the initial welding path to obtain the welding path;

[0116] Interlayer temperature analysis module 3: Used to obtain the interlayer temperature distribution data in the groove body in real time, and generate an interlayer temperature gradient parameter by combining the interlayer temperature distribution data and the interlayer trajectory offset amount;

[0117] Offset analysis module 4: Used to collect the molten pool arc voltage fluctuation data and the droplet transfer frequency characteristics in real time, and correct the three-dimensional coordinate offset amount of the welding torch by combining the arc voltage fluctuation data, the droplet transfer frequency characteristics and the interlayer temperature gradient parameter;

[0118] Welding torch compensation module 5: Used to perform stepped surfacing control according to the preset surfacing layer strategy, activate the side wall staggered welding mode after completing the bottom layer circular continuous welding and generate an inclination compensation control parameter, and perform inclination compensation on the welding torch according to the inclination compensation control parameter;

[0119] Speed adjustment module 6: It is used to obtain the molten pool coverage width, extract the correlation between the interlayer temperature gradient parameter and the molten pool coverage width, and adjust the welding travel speed based on the correlation to maintain a preset fusion area ratio between the constant cladding layer thickness and the molten pool coverage width;

[0120] Welding torch lane-changing module 7: It is used to obtain the cumulative welding layer characteristic value during welding, dynamically match it with the preset groove depth determination threshold according to the cumulative welding layer characteristic value to obtain a matching result, and execute the lane-changing welding instruction according to the matching result until the preset groove termination height reference value is reached.

[0121] A computer-readable storage medium stores a computer program thereon. When the computer program runs on a processor, it executes the above-mentioned PLC-based RTJ groove automatic surfacing method.

[0122] The above are all the preferred embodiments of this application. The protection scope of this application is not limited thereby. Therefore, all equivalent changes made according to the structure, shape, and principle of this application shall be covered within the protection scope of this application.

Claims

1. An automatic surfacing method for RTJ grooves based on PLC, characterized in that, Including the following steps: Establish a reference coordinate system for the groove body and obtain the top width parameter and the inclination angle parameter, and generate an initial welding path according to the geometric relationship between the top width parameter and the inclination angle parameter; Obtain the three-dimensional spatial relationship between the top width parameter and the inclination angle parameter, establish a multi-layer welding trajectory model based on the three-dimensional spatial relationship and generate dynamic welding path data including the interlayer trajectory offset, and obtain the welding path by combining the dynamic welding path data and the initial welding path; Obtain the interlayer temperature distribution data in the groove body in real time, and generate an interlayer temperature gradient parameter by combining the interlayer temperature distribution data and the interlayer trajectory offset; Collect the molten pool arc voltage fluctuation data and the droplet transfer frequency characteristics in real time, and correct the three-dimensional coordinate offset of the welding torch by combining the arc voltage fluctuation data, the droplet transfer frequency characteristics and the interlayer temperature gradient parameter; Execute step-by-step surfacing control according to the preset surfacing layer strategy, activate the side wall staggered welding mode after completing the bottom layer circular continuous welding and generate an inclination angle compensation control parameter, and perform inclination angle compensation on the welding torch according to the inclination angle compensation control parameter; Obtain the molten pool coverage width, extract the correlation between the interlayer temperature gradient parameter and the molten pool coverage width, and adjust the welding travel speed based on the correlation to maintain the preset fusion area ratio between the constant cladding layer thickness and the molten pool coverage width; Obtain the cumulative welding layer number characteristic value during welding, perform dynamic matching according to the cumulative welding layer number characteristic value and the preset groove depth determination threshold to obtain a matching result, and execute a lane-changing welding instruction according to the matching result until the preset groove termination height reference value is reached.

2. The automatic surfacing method for RTJ grooves based on PLC according to claim 1, wherein, The step of generating the initial welding path according to the geometric relationship between the top width parameter and the inclination angle parameter is specifically: Perform three-dimensional contour scanning on the top width parameter of the groove body to obtain the measurement data of the top width parameter, and collect the real-time data of the inclination angle parameter; Select the starting point coordinates and the ending point coordinates in the reference coordinate system of the groove body according to the measurement data and the real-time data; Perform route planning according to the starting point coordinates and the ending point coordinates to generate a planned path, obtain a path curvature characteristic value according to the planned path, and combine the starting point coordinates, the ending point coordinates and the path curvature characteristic value to obtain an initial path data set; Obtain the geometric shape parameters of the welding torch end, and perform equidistant offset processing on the initial path data set according to the geometric shape parameters to obtain a target data set; Obtain the spatial coordinate sequence of the corrected welding center line according to the target data set, and generate an initial welding path according to the spatial coordinate sequence.

3. The automatic surfacing method for RTJ grooves based on PLC according to claim 2, characterized in that, The step of establishing a multi-layer welding trajectory model based on the three-dimensional spatial relationship and generating dynamic welding path data including the interlayer trajectory offset is specifically: Extract data from the target data set to obtain the interlayer trajectory offset parameter in the initial welding path; Obtain the welding layer number, increment the interlayer trajectory offset according to the welding layer number to generate an arithmetic sequence; Obtain the coefficient of thermal expansion of the material and the temperature of the current layer, and generate a thermal deformation compensation amount according to the coefficient of thermal expansion and the temperature of the current layer; Compensate the interlayer trajectory offset parameter according to the thermal deformation compensation amount and the arithmetic sequence to obtain a target offset parameter, and construct a multi-layer welding trajectory model according to the target offset parameter; According to the multi-layer welding trajectory model, obtain a control instruction set for the layer height control threshold and the interlayer overlap rate, and obtain dynamic welding path data based on the instruction set.

4. The method for automatic surfacing of RTJ grooves based on PLC according to claim 3, characterized in that, The step of correcting the three-dimensional coordinate offset of the welding torch, specifically: Based on the arc voltage fluctuation data, obtain the real-time waveform data of the arc voltage, and perform multi-scale decomposition on the real-time waveform data to obtain a voltage fluctuation feature vector; Based on the droplet transfer frequency characteristics, obtain the sequential image data during the droplet transfer process, obtain the standard deviation of the time interval between the formation of adjacent droplets according to the sequential image data, and obtain a transfer stability index according to the standard deviation; Input the voltage fluctuation feature vector and the transfer stability index into a preset prediction model to obtain a lateral offset compensation amount of the welding torch; Input the lateral offset compensation amount into the spatial coordinate register of the welding torch to correct the three-dimensional coordinate offset of the welding torch.

5. The automatic overlaying method for RTJ grooves based on PLC according to claim 1, characterized in that, The step of performing stepped surfacing control according to a preset surfacing layer strategy, specifically: Based on the preset surfacing layer strategy, disassemble the surfacing layer strategy to obtain the total depth of multiple grooves; Arrange the total depth of the grooves to obtain a depth sequence rule, and obtain a layer thickness threshold parameter according to the depth sequence rule; Obtain the current welding layer number, obtain a preset swing amplitude parameter corresponding to the current layer number according to the current welding layer number, and obtain an interlayer swing frequency compensation coefficient according to the swing amplitude parameter and the layer thickness threshold parameter; Generate an acceleration control signal for the periodic swing trajectory of the welding torch according to the interlayer swing frequency compensation coefficient; When the welding torch triggers the acceleration control signal during interlayer transition, generate an inclination compensation parameter according to the layer thickness threshold parameter, and control the welding torch to perform side wall welding according to the inclination compensation parameter.

6. The automatic surfacing method for RTJ grooves based on PLC according to claim 2, characterized in that The step of obtaining the molten pool coverage width, extracting the correlation between the interlayer temperature gradient parameter and the molten pool coverage width, and adjusting the welding travel speed based on the correlation, specifically: Based on the path curvature eigenvalue, monitor the path curvature in real time to obtain the tangent angle difference between adjacent path points, and obtain a path curvature change parameter based on the tangent angle difference; Obtain the current travel speed of the welding torch, establish a quantization relationship model based on the curvature change parameter and the current travel speed, and generate a travel speed adjustment coefficient according to the quantization relationship model; Obtain the molten pool coverage width, and extract the correlation between the interlayer temperature gradient parameter and the molten pool coverage width; Obtain the pulse frequency output value of the servo motor according to the travel speed adjustment coefficient and the correlation, and adjust the welding travel speed according to the pulse frequency output value.

7. The automatic surfacing method for RTJ grooves based on PLC according to claim 6, characterized in that, Dynamically match the cumulative welding layer number characteristic value with a preset groove depth determination threshold to obtain a matching result, and execute a lane-changing welding instruction according to the matching result. Specifically: Based on the welding path, set path nodes on the welding path, and count the number of path points after the welding torch passes through the path nodes to obtain a cumulative welding layer number characteristic value; Dynamically match the cumulative welding layer number characteristic value with the preset groove depth determination threshold to obtain a matching result; Obtain the width uniformity value of the current welding layer and the interlayer fusion area, and obtain a cladding quality evaluation parameter according to the width uniformity value and the interlayer fusion area; Combine the matching result and the cladding quality evaluation parameter to obtain an optimized adjustment amount for the lane-changing distance, and generate a lane-changing path control data set with a smooth transition curve based on the optimized adjustment amount; Generate a lane-changing welding instruction based on the lane-changing path control data set, and call the welding torch for a lane-changing operation according to the lane-changing welding instruction.

8. An automatic surfacing system for RTJ grooves based on PLC, the system using the automatic surfacing method for RTJ grooves based on PLC according to any one of claims 1-7, characterized in that, The system includes: Initial path generation module: used to establish a groove reference coordinate system and obtain a top width parameter and an inclination angle parameter, and generate an initial welding path according to the geometric relationship between the top width parameter and the inclination angle parameter; Path optimization module: used to obtain the three-dimensional spatial relationship between the top width parameter and the inclination angle parameter, establish a multi-layer welding trajectory model based on the three-dimensional spatial relationship and generate dynamic welding path data including interlayer trajectory offset amounts, and combine the dynamic welding path data and the initial welding path to obtain a welding path; Interlayer temperature analysis module: used to obtain the interlayer temperature distribution data in the groove in real time, and generate an interlayer temperature gradient parameter by combining the interlayer temperature distribution data and the interlayer trajectory offset amount; Offset analysis module: used to collect the molten pool arc voltage fluctuation data and the droplet transfer frequency characteristics in real time, and correct the three-dimensional coordinate offset amount of the welding torch by combining the arc voltage fluctuation data, the droplet transfer frequency characteristics and the interlayer temperature gradient parameter; Welding torch compensation module: used to perform stepped surfacing control according to a preset surfacing stratification strategy, activate the side wall staggered welding mode and generate an inclination angle compensation control parameter after completing the bottom layer circular continuous welding, and perform inclination angle compensation on the welding torch according to the inclination angle compensation control parameter; Speed adjustment module: used to obtain the molten pool coverage width, extract the correlation between the interlayer temperature gradient parameter and the molten pool coverage width, and adjust the welding travel speed based on the correlation to maintain a preset fusion area ratio between the constant cladding layer thickness and the molten pool coverage width; Welding torch lane-changing module: used to obtain the cumulative welding layer number characteristic value during welding, dynamically match the cumulative welding layer number characteristic value with a preset groove depth determination threshold to obtain a matching result, and execute a lane-changing welding instruction according to the matching result until a preset groove termination height reference value is reached.

9. A computer-readable storage medium, characterized in that: A computer program is stored on the computer-readable storage medium, and the computer program executes the PLC-based automatic surfacing method for RTJ grooves according to any one of claims 1-7 when running on a processor.

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