Dimensional error during mass production of motorcycle frames are considered to be the accumulation of large deformations (welding distortions) generated by arc welding in each process. In order to satisfy the dimensions of the product, it is necessary to individually grasp the welding distortion generated in each process as a change in the three-dimensional shape, and to adjust the individual three-dimensional behavior of the entire welding line to converge within the tolerance range.
However, it is a method in which one expert figure out the shape changes at intermediate process in his mind from hole position information of the final product and determines the adjustment amount of jigs and parts in each process.
In response to this problem, we have developed a technology to calculate the relative deviation of pre-welded and post-welded parts for each component from pre- and post-weld shape measurement data and CAD data, and to decompose the shape changes that occur before and after welding into “deformation” and “displacement”.
With this technology, it became possible to obtain information on shape changes due to welding, which is the most important for improving accuracy, and it became possible to make accuracy adjustments while tracking three-dimensional changes in the frame shape due to welding.
In addition, we were able to draw out the knowledge and thoughts of experts while reading information on shape changes in each process, and the entire team was able to grasp the welding behavior and shift to a business process that takes countermeasures.
As a result, experts and young engineers became one team, and We were able to achieve the required dimensional accuracy in the production prototype, which also led to the development of young engineers. In this report, we will introduce the new business process that is the key with specific examples.
