【摘要】 曲面分段的建造精度直接影响船体结构的水动力性能及运营成本，其焊接变形的预测和控制，是船舶智能建造的研究难点。以6 mm厚Q235船板钢的单曲率加筋焊接结构为研究对象，在专用胎架上通过二氧化碳（CO₂）气体保护焊，完成曲面分段建造；采用全站仪测量曲面分段上胎、封胎、焊接以及脱胎等状态下的结构形状，通过线切割和抛光腐蚀，获得平角焊接头的宏观金相。基于瞬态的热-弹-塑性有限元方法，分析典型平角焊的热-力学行为以及夹具拘束的影响；通过对比熔池形状，确认计算的可靠性，进而评估出焊接固有变形；建立曲面分段的壳单元网格模型，以焊接固有变形为力学载荷，预测曲面分段的建造精度。研究表明：有限元预测的结果与试验测量数据高度吻合，且焊接纵向收缩是曲面分段产生弯曲变形的主要原因。基于上述先进的焊接变形计算方法，分析拘束距离、满焊等工艺对典型接头焊接变形和曲面分段建造精度的影响，可为后续曲面分段的建造工艺优化提供参考。更多还原

【Abstract】 The fabrication accuracy of the curved section will directly affect the hydrodynamic performance and operating cost of the hull, while prediction and mitigation of welding distortion is the essential issue for intelligent shipbuilding. A single curved welded structure by stiffeners with Q235 of 6 mm is considered, and welding with CO₂ as shielding gas is used to fabricate the investigated single curved section with special bed jig.Meanwhile, total station is used to measure the dimension of the single curved section in the case of free condition on special bed jig, fixture clamping, welding completion and clamping removal; macroscopic metallography testing of fillet welding is carried out with wire cutting, polishing and corrosion processing. Based on transient thermal elastic plastic finite element method, thermal and mechanical behaviors of fillet welding are represented, while the clamping influence is also examined. With the dimensional comparison of welding molten pool, reliability of FE analysis is confirmed, and welding inherent deformation is evaluated. FE mesh model with shell elements of single curved section is created, elastic FE analysis with welding inherent deformation as mechanical loading is carried out to predict fabrication accuracy of single curved section. The calculated result has a good agreement comparing with measurement, and welding longitudinal shrinkage is the dominate cause to generate bending distortion of examined single curved section. Based on the above calculated method, the influence of clamping distance, full welding on welding inherent deformation of fillet welded joint as well as fabrication accuracy of single curved section is also investigated, which could be useful for processing optimization of single curved section fabrication.更多还原