Alternative line delivery strategies support a forklift free transition in a high product variety environment

Forklift transport fails when it comes to efficiency. As a result, more and more attention is going to alternative transport systems that automate or further structure the material flow; such as line deliveries by train and conveyor technology. Only substituting the transport system itself is not cost-effective. The resulting improvements are rather low compared to the high investment cost. Therefore, in this paper alternative material flow and line delivery strategies are taken into consideration. Within a high product variety environment a combination of materials kitting and line stocking is proposed. This approach has some important benefits on top of the pure forklift free transition. A basic model is constructed to calculate the kitting area and transport system requirements. A truck assembly company is used as case study. A feasibility study is carried out, to give a rough indication of the cost-effectiveness of the model

A decision model for kitting

This article gives an overview of the future research directions that will be explored during my PhD. The subject of this research will be parts kitting, or the practice of putting together a collection of components and/or subassemblies that support a certain assembly operation before delivery to the shop floor

Production planning in different stages of a manufacturing supply chain under multiple uncertainties

This thesis focuses on designing stochastic programming models for production planning at different stages in a manufacturing supply chain under multiple sources of uncertainties. Various decision makers along the manufacturing supply chain often have to make planning decisions with embedded risks and uncertainties. In an effort to reduce risks and to ensure that the customer demand is met in the most efficient and cost effective way, the production plans at each stage need to be strategically planned. To assist production planning decisions, a two-stage stochastic programming model is developed with the objective of minimizing the total cost including production, inventory, and backorder costs. The proposed framework is validated with case studies in an automobile part manufacturer with real data based on literature. The results demonstrate the robustness of the stochastic model compared with various deterministic models. Sensitivity analysis is performed for the production capacity parameter to derive managerial insights regarding lot-sizing and scheduling decisions under different scenarios

Análise comparativa em linhas de montagem: impactos da variedade de produtos no abastecimento interno de materiais

TCC(graduação) - Universidade Federal de Santa Catarina, Centro Tecnológico, Engenharia de Produção.Para garantir o nível de serviço, as linhas de montagem devem combinar a operação à logística, com o fornecimento de materiais certos, em quantidades e locais corretos. A logística interna responsável por essa garantia acaba por sofrer variações mediante à variedade de produtos produzida na linha. Um fator influenciador de tal variedade consiste na crescente exigência do mercado, que enfatiza a tendência de customização de produtos e, assim, a necessidade de adaptação da produção para uma maior variedade de produtos. O objetivo central deste trabalho consiste em analisar comparativamente a influência dessa variedade no abastecimento de linha. Portanto, para a presente pesquisa, quatro unidades de análise com diferentes variedades de produtos foram analisadas em um estudo de múltiplos casos, abrangendo linhas uni-modelo, multi-modelo e de modelos mistos. Os resultados obtidos mostram grande relação da variedade de produtos com o fornecimento de peças, frequência de abastecimento e quantidades abastecidas. A existência de lotes de produção torna o abastecimento mais complexo e, por isso, constatou-se a influência positiva da existência de lotes mínimos na padronização de embalagens, do fluxo de informação e de fornecimento. Desse modo, linhas uni-modelo apresentam simplicidade no abastecimento por apresentarem apenas um único modelo de produção. Já as linhas multi-modelo influenciam no planejamento e controle da produção por apresentarem lotes, e linhas de modelos mistos no fornecimento de peças, por necessitarem de embalagens customizadas e com estratégias de abastecimento de sequenciamento e comissionamento.To guarantee the level of service, assembly lines must combine operation with logistics, with the supply of the right materials, in the right quantities and in the right places. The internal logistics responsible for this guarantee ends up suffering variations according to the variety of products produced in the line. An influencing factor of such variety is the growing demand of the market, which emphasizes the trend of product customization and, thus, the need to adapt production to a greater variety of products. The main objective of this work is to comparatively analyze the influence of this variety in line supply models. Therefore, for the present research, four analysis units were made in a multiple case study, with single-model, mixed-model and multi-model lines. Obtained results show a great relationship between the variety of products and the supply of parts, frequency of supply and quantities supplied, as well as the positive influence of the existence of minimum batches in the standardization of packaging, information flow and supply. So, single-model lines show simplicity on supply by having only one production model. Multi-model lines influence production planning and control because of their batches and mixed-model lines influence supply, by needing customized packages with specific supply strategies

In-plant materials supply: Supporting the choice between kitting and continuous supply

This thesis focuses on the two materials feeding principles of “kitting” and “continuous supply” within in-plant materials supply in mass customised assembly. With the principle of kitting, parts are delivered and presented to the assembly operations in pre-sorted kits, with each kit containing parts for one assembly object. With the principle of continuous supply, a number of parts of each part number are presented at the assembly station where they are to assembled, which means that when continuous supply is used in a mixed-model assembly context, where different assembly objects require different parts, the assembler at each assembly station needs to pick the right parts to assemble on each assembly object. Depending on whether kitting or continuous supply is used, the performance of both in-plant materials supply and assembly can be affected. However, within industry, there is considerable confusion regarding which materials feeding principle should be used when. Moreover, the existing research literature on the topic is far from exhaustive. This thesis aims to provide knowledge of how the configuration and the context of the in-plant materials supply system should be considered when a choice between kitting and continuous supply is made. The research has been conducted mainly in the form of case studies at assembly plants within the Swedish automotive industry. Complementing the case studies, one experiment has been conducted. In several of the studies, it has been possible to study both kitting and continuous supply in the same setting, which has resulted in an excellent basis for comparison between the two materials feeding principles. The other studies have instead focused on aspects within each of the two materials feeding principles, enabling an understanding of how each of the two materials feeding principles can be applied and of how this can affect performance. The thesis provides a structured and thorough account of kitting and continuous supply and the effects of using these principles, depending on the configuration and the context of the in-plant materials supply system. This has previously been lacking. The structured and thorough account presented in the thesis contributes to an understanding of the benefits and drawbacks of kitting and continuous supply and the applicability of each of the materials feeding principles. The thesis further relates the choice between kitting and continuous supply to the design of an in-plant materials supply system as a whole and suggests an outline of such a design process