Browsing by Author "Godina, R."
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- Development of a suitable project management approach for projects with parallel planning and executionPublication . Freitas, F.; Silva, Francisco J. G; Campilho, R.D.S.G.; Pimentel, C.; Godina, R.In a big company, project management (PM) is always present. Traditional predictive PM approach is concerned with planning everything in advance and then controlling and adjusting if necessary, throughout the project timeline. This may work well when the requirements are well established, but for maintenance projects brings inherent uncertainty. When the subject is aircraft maintenance, it is almost impossible to plan everything at the beginning and expect that it will occur as planned because however a scheduled maintenance plan exists, according to statistics 60% of the aircraft total failure can only be found with ground inspection which means, that even if a plan is established before receiving the aircraft, it will most certainly need to be significantly changed. This requires a big effort from the planning team to plan everything right and ensure that all tools and resources are available to perform the required tasks. To solve this issue, in this paper we propose a hybrid project management approach developed to a case study company from the aircraft repair sector, to enable a faster planning while taking into account the priorities and dependencies of the inherent project tasks with the available resources.
- Implementing TPM supported by 5S to improve the availability of an automotive production linePublication . Ribeiro, I.M.; Godina, R.; Pimentel, C.; Silva, F.J.G.; Matias, J.C.O.The maintenance management is a topic of strategic importance for automotive manufacturers. In fact, an effective maintenance process and a preventive maintenance (PM) procedure can significantly reduce the risk of equipment failures that can lead to downtime on the production lines. However, due to the complexity of an automotive production system, the risk of failure on a crucial piece of the production equipment cannot be entirely avoided. The study made in this paper aims at improving the availability of a critical production line through the total productive maintenance (TPM) methodology and supported by Lean Maintenance tools. An analysis is made of the initial condition of the line where the main problems are identified by employing several tools for this purpose, such as Mean Time between Failures (MTBF), Mean Time to Repair (MTTR), Overall Equipment Efficiency (OEE) and Availability (A). In response to the identified problems, an action plan is developed and implemented in order to find the root cause of the high number of malfunctions and faults in one of the line’s equipment with the use of 5S tools, visual management, and maintenance progress, as well as the development of a training program to increase operators’ skills. The results of such actions were positive as the line became more organized, the value of the MTBF increased, the MTTR value decreased, and consequently the overall availability increased.
- Influence of textile cord tension in cap ply productionPublication . Costa, C.; Silva, F.J.G.; Campilho, R.D.S.G.; Neves, P.; Godina, R.; Ferreira, S.The deep knowledge about manufacturing processes, as well as their optimization, present themselves as indispensable factors in the search for the best product quality. It is this point of view of continuous improvement that makes companies in profitable and sustainable way. This paper presents a study about unwinding tension of textile cords in the cap ply manufacturing process, using machines called cap-strips for production. In this work, tension can be understood as the tensile force exerted on the cord. This study determines the influence of unwinding tension on the physical and shrinkage properties of the cord, as well as on the properties of cap ply, namely green adhesion and peel adhesion. Furthermore, the impact of cord tension on tire uniformity and the manufacturing process itself was also studied. All conclusions are based on the performed experiments and the execution of statistical tests. This work allows to conclude that the unwinding tension of the textile cords have some impact on the cap ply properties but have no influence on the tire uniformity.
- Production Process Analysis and Improvement of Corrugated Cardboard IndustryPublication . Pereira, Maria Teresa Ribeiro; Neves, A.S.L.; Silva, F.J.G.; Godina, R.; Morgado, Luísa; Pinto, Gustavo FilipeThis work was developed into a corrugated cardboard industrial company. In this sector are produced plans resulting from the union between corrugated cardboard produced and the sheets printed in the previous sector. The PDCA cycle was the main methodology used in this work. Firstly, the initial state of the production was analyzed by data collection in both existent lines and it was concluded that a great variability of the parameters was being used in the process for similar works. The main problems in the process were identified and it was concluded that warp and detached plans were the main reasons for concern. It was implemented a set of measures to reduce these incidences. Control charts were implemented to the starch glue and through the analysis of these charts and cause-effect diagrams several changes to the starch glue circuit and to its own recipe were implemented. The steam pressure of the boiler was reduced from 12 bar to 8 bar and a table with temperatures regarding each paper weight was implemented. The results obtained show that the percentage of waste in the sector was reduced from values ranging between 9 and 12% to values around 4%. Regarding starch glue consumption, it dropped from 11 g/m2 to 8 g/m2. The energy consumption, namely gas, showed a saving of 9%. Thus, this work represents an important contribute to the sector, allowing energy savings and quality and competitiveness improvements.
- Reducing scrap and improving an air conditioning pipe production linePublication . Lopes, R.; Silva, Francisco J. G; Godina, R.; Campilho, R.D.S.G.; Dieguez, T.; Pinto Ferreira, Luís; Baptista, Gabriel A GThe automotive industry is considered one of the most demanding and competitive sectors in the global market. This increasingly implies having a stable and optimized production process, always with a view to continuous improvement. Therefore, it is very important to be aware of all the waste that is generated in all production and logistics operations and take action to reduce them. In this regard and considering the process of producing air conditioning pipes for the automotive industry, a high scrap value was detected mainly due to soldering process. Therefore, the entire production process is analyzed in order to identify the main causes behind the high scrap value. Several Lean and quality tools are used to reduce not only the amount of scrap but also to increase the line productivity. In order to face this challenge, after elaborating the action plan and corresponding implementation, the scrap value is reduced by 12% in general, and productivity increased by 29%, 55% and 22.5% in three different references produced by the same machine. Although this solution is a bit expensive, the corresponding payback is reduced, so it can easily be applied transversally to other similar machines allowing extremely interesting gains in the short term.