Browsing by Author "Silva, F.J.G."
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- Analysis and optimisation of a logistic warehouse in the automotive industryPublication . Caridade, R.; Pereira, Maria Teresa; Ferreira, Luís Pinto; Silva, F.J.G.The automotive industry is one of the most competitive sectors, in which rigour, flexibility, quality and agility constitute the critical factors of success. Warehouse activities and their associated costs play a vital role in logistic functions. Their optimisation and performance assessment may result in substantial value gains for the company. This study was developed at Continental Mabor, with the purpose of developing a proposal to restructure and optimise the company’s warehouse. An analysis of the existing warehouse was carried out and the respective proposals were subsequently presented. The main goal of these proposals was to improve the efficiency of warehouse functions, reduce stock quantities and enhance the capacity to meet customer’s demand. A warehouse management system (WMS) was installed and a suitable bin management solution was defined. This system consisted of a basic WMS to support stock inventory and its location. In addition, this system envisaged warehouse performance and included elements such as the inventory management Key Performance Indicator (KPI) and warehouse productivity.
- Analysis Of An Order Fulfilment Process At A Metalwork Company Using Different Lean MethodologiesPublication . Dias, José António; Ferreira, Luís Pinto; Gonçalves, Maria A.; Silva, F.J.G.; Ares, EnriqueThis article presents the analysis of a process by using four distinct approaches, each of them recurring to different Lean tools in order to get a detailed and multidimensional overview of the process. The primary objective of this study was to identify activities which add value in the order fulfilment process of a metalwork company. In this context, one also addressed issues such as waste, problems and their causes, in order to define intervention priorities and select actions capable to enhance the performance and efficiency of the process. The secondary objective was to evaluate and compare the results of the analysis made through different mapping techniques. From this study results the proposal of a tool to identify perceived micro-inefficiencies, as well as the impact of these on the production sub-process. Designated as Perceived Waste Mapping (PWM), this method allowed one to estimate that the ratio between the value-added hours and the total number of work hours at the company will be approximately 30%, far from the figure of 84% registered in the existing time and production records.
- Applying SMED methodology in cork stoppers productionPublication . Sousa, E.; Silva, F.J.G.; Ferreira, Luís Pinto; Pereira, Maria Teresa; Gouveia, R.; Silva, R.P.Organizations are increasingly required to have a high level of quality and flexibility in production. In order to remain in the market and become competitive, the working methods practiced must be reliable and efficient. The present project sought the improvement of an equipment of the cork industry by introducing a variation, through the application of Lean methods. The equipment under study performs the union of a cork stopper to a capsule, which is done by gluing it with hot-melt glue. The amount of production makes the changeover activity a regular process. The method followed in this work was the study and collection of information on the Lean production philosophy and its application in the cork industry. The working conditions of the assembly machine were also analyzed in order to find opportunities for improvement. Thus, the tool used was the Value Stream Mapping (VSM) technique in order to acknowledge the processes that really add value to the product. The SMED (Single Minute of Exchange of Die) methodology was applied in a way to reduce the downtime caused by tool changes, and a reduction of 43% in total changeover time was obtained. It was also created an A3 model to monitor the entire development of the SMED project, Finally, the OEE (Overall Equipment Efficiency) calculation was implemented as an indicator of overall equipment efficiency, in order to improve the monitoring of possible deviations during production. The feedback also proves that lean tools are a powerful method to get solid returns without large investments.
- A case study on the eco-efficiency performance of a composite processing industry: evaluation and quantification of potential improvementsPublication . Ribeiro, M.C.S.; Meira Castro, Ana C.; Silva, F.J.G.; Meixedo, JP; Oliveira, L.; Alvim, M.R.; Fiúza, A.; Dinis, M.L.In this study, an attempt was made in order to measure and evaluate the eco-efficiency performance of a pultruded composite processing company. For this purpose the recommendations of World Business Council for Sustainable Development (WCSD) and the directives of ISO 14301 standard were followed and applied. The main general indicators of eco-efficiency, as well as the specific indicators, were defined and determined. With basis on indicators’ figures, the value profile, the environmental profile, and the pertinent eco-efficiency ratios were established and analyzed. In order to evaluate potential improvements on company eco-performance, new indicators values and eco-efficiency ratios were estimated taking into account the implementation of new proceedings and procedures, at both upstream and downstream of the production process, namely: i) Adoption of a new heating system for pultrusion die-tool in the manufacturing process, more effective and with minor heat losses; ii) Recycling approach, with partial waste reuse of scrap material derived from manufacturing, cutting and assembly processes of GFRP profiles. These features lead to significant improvements on the sequent assessed eco-efficiency ratios of the present case study, yielding to a more sustainable product and manufacturing process of pultruded GFRP profiles.
- Characterization of hybrid pultruded structural products based on preformsPublication . Silva, F.J.G.; Baptista, Andresa; Pinto, Gustavo Filipe; Campilho, R.D.S.G.; Ribeiro, M.C.S.Pultrusion is a widely known technique for production of constant cross-section profiles, such as bars, L-shape or T-shape profiles, as well as structural tubes in polymer matrix composite materials. In some applications, requirements are demanding for profiles able to provide better thermal or sound insulation or needing a slightly higher moment of inertia without increasing the ratio between weight and strength. In such cases, hybrid pultruded profiles with core based on preforms are a possible solution. After obtaining prototypes according to the methodologies described in a previous work, and as a complement to that work, it is necessary to verify if the properties of these hybrid profiles correspond to the initial expectations, by performing destructive and non-destructive tests. Thus, tensile, compression and bending tests were performed, in order to verify the mechanical benefits achieved through the core introduction into the hollow profile and to analyse the added value brought by these new products. These values, once properly validated, can be added to existing databases related to structural calculation programs, enabling to get the adequate values for calculations regarding this kind of profiles. In addition, thermal and acoustic insulation tests were performed, in order to quantify the physical improvements achieved regarding these properties, which are extremely important in specific applications linked to the civil construction and public works, among many others. The cored profiles showed a strong adhesion between the profile and any kind of core tested as well as improved properties in terms of thermal insulation and moment of inertia. However, the sound insulation did not present significant improvements, probably due to GFRP profile external rigidity and consequent reflection.
- A codification system roadmap: case study in a metalworking companyPublication . Lemos, Carlos; Pereira, Maria Teresa; Ferreira, Luís Pinto; Silva, F.J.G.Decision-making and control of operational areas in industrial companies are key issues in their sustainability and resilience in markets that are more and more challenging and competitive. In this way, production management and information management software are becoming mandatory. The codification of information, namely products codification, is a subject, without being the main purpose in everyday companies’ work, must be a subject that enables a proper functioning of everyday companies’ activity. This project proposes a roadmap for internal product codification in a company working in the metalworking industry. This guide shows good practices that highlight formal basic rules whose could add value to internal processes of the organization and so to provide a solid system where the company can rely on providing more time to its workers to spend in other tasks. At last it is provided a generic conceptual model to serve as an approach to develop a codification system in any given organization.
- Comparative evaluation of adhesively-bonded single-lap and stepped-lap jointsPublication . Silva, J.O.S.; Campilho, R.D.S.G.; Rocha, R.J.B.; Silva, F.J.G.Several adhesive joint configurations are available, namely butt joints, single-lap joints (SLJ), double-lap joints and scarf joints. Stepped-lap joints, which are not so studied, consist of a finite number of steps in the bonded area, possessing stress concentrations at all step edges instead of only at the bonded length edges. Stepped-lap joints increase the maximum load (Pm) over SLJ. The present study experimentally and numerically evaluates the static tensile strength of SLJ and stepped-lap joints bonded with the moderately ductile adhesive Araldite® 2015, considering varying values of overlap length (LO). A Finite Element Method (FEM) analysis was carried out to compare through-thickness normal (σy) and shear (τxy) stresses in the bondline between joint configurations. Additionally, a Cohesive Zone Modelling (CZM) analysis was considered to study the failure modes and to evaluate the CZM technique’s accuracy. Between SLJ and stepped-lap joints, the improved stress distributions of the stepped-lap joints resulted in higher joint performance, especially for higher LO. The CZM model revealed to be accurate in predicting Pm.
- Comparison of different test configurations for the shear fracture toughness evaluation of a ductile adhesivePublication . Leal, A.J.S.; Campilho, R.D.S.G.; Silva, F.J.G.; Silva, D.F.O.; Moreira, F.J.P.Cohesive zone modelling (CZM) is widely used for predicting the strength of adhesive joints. The key variable for crack path modelling is the critical strain energy release rate (GC), which can be separated into the tensile (GIC) and shear (GIIC) components. In shear, the End Notched Flexure (ENF) test is widespread. However, other test methods exist and could be a viable replacement. This work aims to make a numerical evaluation between the ENF and Four-Point End Notched Flexure (4ENF) tests to determine GIIC of a ductile adhesive (SikaForce® 7752) and to provide shear CZM laws for further application in design. An inverse technique was used to obtain the shear CZM laws of the adhesive. It was concluded that the GIIC values obtained by the ENF and 4ENF tests are in good agreement. The numerical analysis led to unique shear CZM laws for both tests, with similar results.
- Continuous improvement in maintenance: a case study in the automotive industry involving Lean toolsPublication . Pinto, Gustavo Filipe; Silva, F.J.G.; Campilho, R.D.S.G.; Casais, R.B.; Fernandes, A.J.; Baptista, AndresaMaintenance function assumes a key role in today’s industry. The automotive industry is not an exception and there are strict rules to comply with. Indeed, the IATF 16949:2016 imposes the implementation of key performance indicator as a mean to control the overall manufacturing performance. This work presents a case study carried out in a multinational company related with the production of parts for the automotive industry where it was necessary to implement key performance indicators to comply with the IATF 16949: 2016 standard and a model was also created for the management of spare parts linked to the maintenance of existing equipment. The introduction of these changes forced the application of some Lean tools, with a view to improving procedures and information flows. The work was completed successfully, and key performance indicators were implemented, whose support data, which is now collected and calculated automatically on a routine basis, and the spare-parts management was validated with a view to optimization of warehouse space and at a conveniently low inventory level in this type of parts, without endangering critical equipment in production. The SMED methodology was applied, which allowed the setup time to be reduced by 11%, and the Lean 5S tool was used to organize the mould exchange activities. An OEE of more than 90% has been achieved.
- Cost reduction and quality improvements in the printing industryPublication . Moreira, A.; Silva, F.J.G.; Correia, A.I.; Pereira, Maria Teresa; Ferreira, Luís Pinto; Almeida, F. deCompetitiveness has been the key factor for the survival of the companies. The economic crisis that marked the beginning of this millennium forced the total readjustment of processes and operations which, in some cases, gave origin to deep changes in the organizations. In addition, concerns and consequent environmental constraints have begun to increase. Printing industry was strongly influenced by these factors. This study aims to reduce the use of toxic products and general costs in offset printing process, as well as promote a productivity increase in the printing industry. Because this kind of industry is largely influenced by weather conditions, historical data was collected, allowing to reach the balance between the printing consumables usage and working methodologies, leading to implementing important improvements. At the end of the study, it was possible to observe very good results, increasing the Overall Equipment Effectiveness (OEE) and the Mean Time Between Failure (MTBF) and reducing the Mean Time To Repair (MTTR) relatively to the equipment. The biggest achievement was the massive reduction of the isopropyl alcohol consumption in the offset printing process, increasing the air quality at the facilities, reducing the costs and most of the problems during the printing process.