Programming method for writing special-shaped curved surface surfacing alloy welding program based on KOT-S software

Abstract

The invention discloses a programming method for writing a special-shaped curved surface surfacing alloy welding program based on KOT-S software, and relates to the technical field of special-shaped curved surface surfacing. The programming method comprises the following steps that S1, a physical reference system is established in a blank non-welding area based on a numerical control machining center; s2, a modular positioning clamp is adopted to achieve benchmark matching of the blank and the theoretical model; s3, welding bead track planning and process auxiliary body modeling based on NX software; s4, format conversion is achieved through a CAD-MDL conversion engine; s5, a welding program is written, simulated and verified in the KOT-S environment; and S6, safe transmission and quality feedback control of the welding program are carried out. The method does not depend on experience of field operators, regenerative welding can be achieved by calling a welding program, meanwhile, manual intervention time is shortened, and welding efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of special-shaped curved surface surfacing welding, and in particular to a programming method for writing a special-shaped curved surface surfacing welding alloy welding program based on K_OT-S software. Background Art

[0002] As a surface strengthening technology, hardfacing significantly enhances a workpiece's wear resistance, high temperature resistance, or corrosion resistance by depositing one or more layers of alloy materials with specialized properties onto a high-strength substrate. This technology is widely used in the energy industry, aerospace, equipment manufacturing, marine engineering, and other fields. With the advancement of industrial automation, welding robots have become a core component of hardfacing.

[0003] At present, the welding robot cladding internal mixer for special-shaped curved alloys is programmed by online teaching and point selection. The operator needs to reasonably plan the welding sequence based on the characteristics of the workpiece and the distribution of the surface in combination with the welding process, and write an independent welding program for each surface in units of surface. According to the surface shape and the change law of the surface curvature, the weld bead is planned under the premise of meeting the process requirements. Each weld is fitted into a continuous welding trajectory with multiple evenly distributed discrete points. The welding parameters of each teaching point need to be judged by the operator's experience and human observation. After adjusting to the reasonable posture of the welding gun and the workpiece, the corresponding teaching point can be recorded. The welding program is recorded one by one according to these trajectory teaching points. Through the function of the robot control system, these discrete points are fitted into a continuous welding trajectory by interpolation of straight lines, arcs or curves to form a trajectory program for a single weld bead.

[0004] The above method has certain limitations. The rationality of its welding trajectory generation depends on manual experience, and deviations are prone to occur during manual observation. The welding procedure has poor versatility. On-site teaching is greatly affected by the environment, and there are many interference factors such as welding equipment and work sites. At the same time, teaching programming is prone to errors and is not safe enough. The programming process takes a long time on the machine. Summary of the Invention

[0005] The purpose of the present invention is to provide a programming method for writing a welding program for special-shaped curved surface surfacing alloy based on K_OT-S software to solve the above-mentioned shortcomings in the technology.

[0006] In order to achieve the above object, the present invention provides the following technical solution: a programming method for writing a welding program for a special-shaped curved surface surfacing alloy based on K_OT-S software, comprising the following steps:

[0007] Step S1: establishing a physical reference system in the non-welding area of the blank based on a CNC machining center;

[0008] Step S2: using a modular positioning fixture to achieve benchmark matching between the blank and the theoretical model;

[0009] Step S3: welding trajectory planning and process auxiliary body modeling based on NX software;

[0010] Step S4: Implementing format conversion through the CAD-MDL conversion engine;

[0011] Step S5: Welding program writing, simulation and verification in K_OT-S environment;

[0012] Step S6: Safe transmission of welding procedures and quality feedback control.

[0013] Preferably, the step S1 includes:

[0014] S1-1: Use CNC gantry machining center to mill the blank and reference points to ensure the consistency between the model and the actual object;

[0015] S1-2: Establish a mapping relationship with the theoretical reference points of the three-dimensional model and generate a reference data package containing the reference point coordinates, normal vector direction and processing error matrix.

[0016] Preferably, the step S2 includes:

[0017] S2-1: Design a modular fixture and install it to match the blank reference point;

[0018] S2-2: The actual reference point coordinates are collected through the robot teaching pendant, and the coordinate system offset Δ is calculated using the least squares fitting algorithm;

[0019] S2-3: When the offset exceeds the threshold, an alarm is triggered and the installation is suspended. The compensation parameters are automatically loaded through the arc sensing system.

[0020] Preferably, step S3 includes:

[0021] S3-1: In the NX modeling environment, the special-shaped surface is divided into multiple welding subdomains based on the welding heat-affected zone prediction model, and a 3mm transition zone is set at the boundary of each subdomain;

[0022] S3-2: Use the surface streamline algorithm to generate the weld path, which meets the following requirements:

[0023] The error of the distance between adjacent welds is ≤±0.15mm;

[0024] Track curvature continuity is G2 or above;

[0025] Welding gun posture angle change rate ≤ 5° / s;

[0026] S3-3: Generate a cylindrical auxiliary body with a diameter matching the welding gun nozzle at the turning point of the weld bead, and the deviation angle α between its axis and the surface normal vector satisfies tanα≤0.05.

[0027] Preferably, the surface streamline algorithm includes:

[0028] a) Dynamically adjust the sampling density according to the curvature radius;

[0029] b) Using B-spline curve to fit discrete points;

[0030] c) Insert virtual control points for high curvature areas.

[0031] Preferably, step S4 includes:

[0032] S4-1: Repair model surface damage through CADCNV conversion engine;

[0033] S4-2: Classify and save the processed models, tooling, auxiliary bodies and weld trajectory lines by category, and use CADCNV software to convert them into MDL format that can be read by K_OT_S.

[0034] Preferably, step S5 includes:

[0035] S5-1: Import the MDL format file data into K_OT_S software;

[0036] S5-2: Establish kinematic model of six-axis welding robot and positioner;

[0037] S5-3: Based on the pre-processed model and auxiliary bodies, the welding program is written based on the surface, the distribution of discrete teaching points and the reference geometry;

[0038] S5-4: Solve the welding gun posture to ensure that the TCP position error is ≤ 0.1mm;

[0039] S5-5: Perform trajectory simulation verification and monitor the safe distance between the welding gun and the tooling.

[0040] Preferably, step S6 includes:

[0041] S6-1: Set access control for welding procedures;

[0042] S6-2: Call the repair welding program according to the manual inspection results;

[0043] S6-3: Establish a welding parameter database and set welding conditions according to welding materials and processes. Different welding parameters can achieve a variety of welding conditions such as welding wire, shielding gas, and wire extension length.

[0044] In the above technical solution, the technical effects and advantages provided by the present invention are:

[0045] 1. Utilize the surface editing function of NX software and combine it with the welding process to plan the weld trajectory and auxiliary body, so that the cladding welds are evenly arranged and the trajectory fitting accuracy is higher;

[0046] 2. Import the established model and tooling into the K_OT-S robot offline programming software, build a virtual welding environment on the software, and write and simulate welding programs based on pre-arranged trajectories and reference geometries, improving safety while also being unaffected by environmental factors.

[0047] 3. It does not rely on the experience of on-site operators. The welding program can be called to regenerate welding, while reducing manual intervention time and improving welding efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments described in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0049] Figure 1 Flow chart of the method of the present invention. DETAILED DESCRIPTION

[0050] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0051] The present invention provides Figure 1 A programming method for writing a welding program for a special-shaped curved surface cladding alloy based on K_OT-S software is shown, comprising the following steps:

[0052] Step S1: establishing a physical reference system in the non-welding area of the blank based on a CNC machining center;

[0053] Step S1 includes:

[0054] S1-1: Use CNC gantry machining center to mill the blank and reference points to ensure the consistency between the model and the actual object;

[0055] S1-2: Establish a mapping relationship with the theoretical reference points of the three-dimensional model and generate a reference data package containing the reference point coordinates, normal vector direction and processing error matrix.

[0056] Step S2: using a modular positioning fixture to achieve benchmark matching between the blank and the theoretical model;

[0057] Step S2 includes:

[0058] S2-1: Design a modular fixture and install it to match the blank reference point;

[0059] S2-2: The actual reference point coordinates are collected through the robot teaching pendant, and the coordinate system offset Δ is calculated using the least squares fitting algorithm;

[0060] S2-3: When the offset exceeds the threshold, an alarm is triggered and the installation is suspended. The compensation parameters are automatically loaded through the arc sensing system.

[0061] Step S3: welding trajectory planning and process auxiliary body modeling based on NX software;

[0062] Step S3 includes:

[0063] S3-1: In the NX modeling environment, the special-shaped surface is divided into multiple welding subdomains based on the welding heat-affected zone prediction model, and a 3mm transition zone is set at the boundary of each subdomain;

[0064] S3-2: Use the surface streamline algorithm to generate the weld path, which meets the following requirements:

[0065] The error of the distance between adjacent welds is ≤±0.15mm;

[0066] Track curvature continuity is G2 or above;

[0067] Welding gun posture angle change rate ≤ 5° / s;

[0068] S3-3: Generate a cylindrical auxiliary body at the turning point of the weld bead with a diameter matching the welding gun nozzle, and the deviation angle α between its axis and the surface normal vector satisfies tanα≤0.05;

[0069] Surface streamline algorithms include:

[0070] a) Dynamically adjust the sampling density according to the curvature radius;

[0071] b) Using B-spline curve to fit discrete points;

[0072] c) Insert virtual control points for high curvature areas

[0073] Step S4: Implementing format conversion through the CAD-MDL conversion engine;

[0074] Step S4 includes:

[0075] S4-1: Repair model surface damage through CADCNV conversion engine;

[0076] S4-2: Classify and save the processed models, tooling, auxiliary bodies and weld trajectory lines by category, and use CADCNV software to convert them into MDL format that can be read by K_OT_S.

[0077] Step S5: Welding program writing, simulation and verification in K_OT-S environment;

[0078] Step S5 includes:

[0079] S5-1: Import the MDL format file data into K_OT_S software;

[0080] S5-2: Establish kinematic model of six-axis welding robot and positioner;

[0081] S5-3: Based on the pre-processed model and auxiliary bodies, the welding program is written based on the surface, the distribution of discrete teaching points and the reference geometry;

[0082] S5-4: Solve the welding gun posture to ensure that the TCP position error is ≤ 0.1mm;

[0083] S5-5: Perform trajectory simulation verification and monitor the safe distance between the welding gun and the tooling.

[0084] Step S6: Safe transmission of welding procedures and quality feedback control;

[0085] Step S6 includes:

[0086] S6-1: Set access control for welding procedures;

[0087] S6-2: Call the repair welding program according to the manual inspection results;

[0088] S6-3: Establish a welding parameter database and set welding conditions according to welding materials and processes. Different welding parameters can achieve a variety of welding conditions such as welding wire, shielding gas, and wire extension length.

[0089] The present invention utilizes the surface editing function of NX software in combination with the welding process to plan the weld trajectory and auxiliary body, so that the cladding welds are evenly arranged and the trajectory fitting accuracy is higher; the established model and tooling are imported into the K_OT-S robot offline programming software, a virtual welding environment is built on the software, and the welding program is written and simulated according to the pre-arranged trajectory and reference geometry, which improves safety while being unaffected by environmental factors; it does not rely on the experience of on-site operators, and welding can be reproduced by calling the welding program, while reducing manual intervention time and improving welding efficiency.

[0090] The above description is merely illustrative of certain exemplary embodiments of the present invention. It goes without saying that those skilled in the art will be able to modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the scope of protection of the claims.

Claims

1. A programming method for writing a welding program for special-shaped curved surface surfacing alloy based on K_OT-S software, characterized in that: The following steps are involved: Step S1: establishing a physical reference system in the non-welding area of the blank based on a CNC machining center; Step S2: using a modular positioning fixture to achieve benchmark matching between the blank and the theoretical model; Step S3: welding trajectory planning and process auxiliary body modeling based on NX software; Step S4: Implementing format conversion through the CAD-MDL conversion engine; Step S5: Welding program writing, simulation and verification in K_OT-S environment; Step S6: Safe transmission of welding procedures and quality feedback control.

2. The method for programming a special-shaped curved surface surfacing alloy welding program based on K_OT-S software according to claim 1, characterized in that: The step S1 comprises: S1-1: Use CNC gantry machining center to mill the blank and reference points to ensure the consistency between the model and the actual object; S1-2: Establish a mapping relationship with the theoretical reference points of the three-dimensional model and generate a reference data package containing the reference point coordinates, normal vector direction and processing error matrix.

3. The method for programming a special-shaped curved surface surfacing alloy welding program based on K_OT-S software according to claim 1, characterized in that: The step S2 comprises: S2-1: Design a modular fixture and install it to match the blank reference point; S2-2: The actual reference point coordinates are collected through the robot teaching pendant, and the coordinate system offset Δ is calculated using the least squares fitting algorithm; S2-3: When the offset exceeds the threshold, an alarm is triggered and the installation is suspended. The compensation parameters are automatically loaded through the arc sensing system.

4. The method for programming a special-shaped curved surface surfacing alloy welding program based on K_OT-S software according to claim 1, characterized in that: The step S3 comprises: S3-1: In the NX modeling environment, the special-shaped surface is divided into multiple welding subdomains based on the welding heat-affected zone prediction model, and a 3mm transition zone is set at the boundary of each subdomain; S3-2: Use the surface streamline algorithm to generate the weld path, which meets the following requirements: The error of the distance between adjacent welds is ≤±0.15mm; Track curvature continuity is G2 or above; Welding gun posture angle change rate ≤ 5° / s; S3-3: Generate a cylindrical auxiliary body with a diameter matching the welding gun nozzle at the turning point of the weld bead, and the deviation angle α between its axis and the surface normal vector satisfies tanα≤0.

05.

5. The method for programming a special-shaped curved surface surfacing alloy welding program based on K_OT-S software according to claim 4, characterized in that: The surface streamline algorithm includes: a) Dynamically adjust the sampling density according to the curvature radius; b) Using B-spline curve to fit discrete points; c) Insert virtual control points for high curvature areas.

6. The method for programming a special-shaped curved surface surfacing alloy welding program based on K_OT-S software according to claim 1, characterized in that: The step S4 comprises: S4-1: Repair model surface damage through CADCNV conversion engine; S4-2: Classify and save the processed models, tooling, auxiliary bodies and weld trajectory lines by category, and use CADCNV software to convert them into MDL format that can be read by K_OT_S.

7. The method for programming a special-shaped curved surface surfacing alloy welding program based on K_OT-S software according to claim 1, characterized in that: The step S5 comprises: S5-1: Import the MDL format file data into K_OT_S software; S5-2: Establish kinematic model of six-axis welding robot and positioner; S5-3: Based on the pre-processed model and auxiliary bodies, the welding program is written based on the surface, the distribution of discrete teaching points and the reference geometry; S5-4: Solve the welding gun posture to ensure that the TCP position error is ≤ 0.1mm; S5-5: Perform trajectory simulation verification and monitor the safe distance between the welding gun and the tooling.

8. The method for programming a special-shaped curved surface surfacing alloy welding program based on K_OT-S software according to claim 1, characterized in that: The step S6 comprises: S6-1: Set access control for welding procedures; S6-2: Call the repair welding program according to the manual inspection results; S6-3: Establish a welding parameter database and set welding conditions according to welding materials and processes.

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