船用低温高强钢三维多层焊接变形有限元模拟

3D finite element simulation on distortion distribution in multi layers welding of EH36

关键词:  船用钢  三维多层焊  变形  模拟

Key words:  EH36 steel  multi-layers  distortion  simulation

摘要:

低温高强钢EH36在船舶重要结构部位应用广泛。采用有限元软件,根据EH36钢热物理特性,对其焊接温度场和焊接变形进行了数值模拟。通过选择具备热和结构功能的耦合单元,应用APDL二次开发语言和生死单元技术,在三维方向上,对开坡口厚板的多层焊焊接热循环过程进行了分析,得到工件收缩变形及角变形等数据。结果表明,第一层焊接变形与第二层焊接变形大小和趋势存在差异,而后焊部位的焊接变形也不同于先焊部位。通过常见的V形坡口和U形坡口焊接变形大小的比较,在坡口截面尺寸相同的情况下,得到U形坡口焊接角变形明显小于V形坡口的结论。

Abstract:

As one of low temperature high strength steel, EH36 is widely used in key construction of ship.Based on the thermal-physical properties of EH36, 3D finite element simulation is carried out to analyse the temperature field and distortion distribution. To simulate the actual welding process, some technologies, such as APDL program used for development and birth &death skill, are applied in 3D multi passes welding.Thus the temperature field and weld distortion distribution in 3-directions are obtained.The result of simulation shows that there are many different distortions between the first pass and the second one, and that difference lies between the firstly welded part first and the later welded part.Further, the distortions of U-shape groove and V-shape groove were compared, the angle deformation of workpieces with V-shape groove is obviously greater than that of the U-shape groove at the same area of weld crass-section, both of them share with the same areas, same welding process and simulation process.