2015 年 81 巻 823 号 p. 14-00670
As a rationalization way of power generating plant construction using three-dimensional measurement, the calculation approach of optimum cutting surfaces of extra length parts which are given at both ends of pipe spools has been developed. In piping work between two pieces of equipment, pipe spools are sequentially welded from one side to the other side. At this time, a little amount of installation error which derives from welding distortion and manufacturing error of each spool is piled up on the piping route. Thus, the last pipe spools which are connected between the terminal equipment and a next-to-last pipe spools, have extra length parts at both ends to adjust the installation error, and are cut at appropriate position at the construction sites. But it is difficult to estimate accurate cutting amount at the construction site because the extra length parts often have to be cut diagonally with respect to original end faces to fit the last pipe spools with high accuracy to existing pipes which have three-dimensional misalignments. So, in this study, the connecting position of the last pipe spools into existing pipes which makes the diagonal cutting angles of both pipe ends even and minimum has defined as the optimum solution, and calculation approach to get the optimum solution has been developed. As results of verification test with using mock up pipes and trial use at construction site, the validity of the calculation approach has confirmed.
