Production ramp up corresponds to the period between the end of the production development and the full capacity utilization. The manufacturing process often does not work perfectly during this early time of the new product production and some adjustments are necessary to obtain full capacity utilization.
In order to assess the assembly process during this period, the train manufacturer Bombardier Transportation has created an improvement process called “VPI” (which stands for “Validation du Processus Industrial” or “Validation of the manufacturing process” in English).
Its purpose is to “validate the material and the documentation for every movement independently” in order to ensure quality of final product and safety of the workers. It aims at detecting and solving rapidly safety problems and deviation from the normal process.
This thesis is a case study of VPI during MI09 contract (new trains for ¨Paris subway). It aims at assessing VPI framework and identifies possible causes of the delay in validation of MI09 production process. Four main MI09 production line specificities have been identified: long assembly time, low production volume, system complexity and process variability.
VPI framework meets partially these production line prerequisites. VPI is a process that allows systematizing problems detection, formalizing the improvement process and managing a high number of problems with a clear view of the VPI validation. The most important drawbacks of the VPI seem to be the lack of problems detection after the initial observation, problem definition framework and root cause analysis.
Four reasons could explain the delays during the realization of VPI on MI09 contract: undetected problems, normal treatment timeframe for the improvements, inadequate objectives and lack of framework to select the best solution to solve problems.
VPI may be improved by including root cause analysis, better problem definition and knowledge management between contracts. However, these methods are time consuming and a prioritization of the problem should be made. FMEA (Failure Mode and Effect Analysis) methodology may help to identify the problem on which the VPI should focus on.
Source: Linköping University
Author: Taret, Benjamin