The Research On The Robot Saddle-shape Cutting Technology Of Marine Structure

The paper lays emphasis on the current cutting situations of saddle-shape structurewhen the angle of pipes is90°,domestically and internationally, and found that most of ourdomestic shipyards are still cutting by traditional oxyacetylene cutting and cutting ofsaddle-shape structure. However, both methods have their limitations. Artificialsaddle-shape cutting can’t ensure the continuity and accuracy of the curves and the cuttingquality is directly connected with the experience and health of the workers. Thesaddle-shape cutting machine selling on the market all can cut precise saddle-shape curves,but handling of grooves aren’t well satisfied, so it can just cut grooves with regular assuredangle and cannot meet the requirements of changing. Because of the current situations, a setof off-line programming system applying for the robotic saddle-shape cutting of pipes inshipping was designed.In light of the limitations on hardware equipment, a positioned system with a singleaxis rotation is designed and the whole application range has been expanding. There arethree major modes for saddle-shape cutting. First and foremost, robot itself completes thewhole cutting task. Second, both robot and the positioned support the task. And finally, therobot and positioned finish the task synchronous.The modeling task of the whole system can be finished by usage of SolidWorks,three-dimensional drawing software. Drawing the90°intersection line with CAD canresearch the detailed characters of the intersection line, thus the deduction of saddle-shapeteaching formula and formula for revising angle can be obtained. Develop the KUKAoff-line programming software. The window includes some referring parameters such asexternal diameters of the main and branching pipes、thickness、cutting speed and accuracy ofthe trails. Different output modes are also designed to meet actual needs of customers.Analog simulation and entity simulation can be gained by the referring points ofsaddle-shape trails calculated by MATLAB software, and the accuracy and feasibility of thewhole system is proved. A host of cutting experiments show that the cutting trail of the mainpipe is precise、the cut is clean and relevant technical requirements can be met when thepressure of oxygen and ethylene is0.6MPa and0.046-0.05MPa respectively、the heightfrom cutting regime to the plate is6mm and cutting speed is0.48-0.72m/min. Greatbranching pipe saddle-shape groove can be gained and production needs can be met when the pressure of oxygen and ethylene is0.6MPa and0.045MPa respectively、the height fromcutting regime to the plate is5mm and cutting speed is1.08-1.32m/min.The actual intersected groove angle between the main and branching pipes is basicallyidentical by the spot welding equipment experiment applying to the cut main and branchingpipes. The results demonstrate that the cutting experiments of changing grooves aresuccessful and thus confirm the feasibility of the whole cutting system.