Improvement of the estimation method caused by welding in hull built-up stages

提高船体各构件的匹配精度是引进经济型自动焊接机的关键。精确的焊接变形估计方法也是实现这一目标的必要条件。为了实现上述目标，进行了以下研究项目。1)本研究提出了一种实用的焊接构筑物焊接变形估计方法。等效固有应变法是一种计算大型焊接建筑结构焊接变形的简便方法。2)纵向收缩估算精度的提高是不可避免的，因为大型焊接建筑结构的纵向收缩量与焊接引起的横向收缩量几乎是同一量级的。用腱力的概念来量化纵向收缩是非常方便的。为了从热输入信息中估计出腱力，开发了高精度的PC软件。

Improvement of matching accuracy of each hull block element is essential to introduce the economical automatic welding machines in an assembly stage.Precise estimation method of the welding deformation is also necessary to achieve the aim.Following research items were performed in order to achieve above object.1) Development of a useful estimation method of the welding deformation about welded built-up structures is developed in this research. Equivalent inherent strain method is highlighted as a convenient estimation method about welding deformation in large welded built-up structures.2) Improvement of the estimation accuracy in the longitudinal shrinkage is inevitable, because the amount of longitudinal shrinkage in large welded built-up structures is almost same order with transverse shrinkage caused by welding. A concept of tendon force is very convenient to quantify longitudinal shrinkage. High accuracy PC software was developed in order to estimate tendon force from heat input information.