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1 – 10 of over 5000Yongming Wu, Xudong Zhao, Yanxia Xu and Yuling Chen
The product family assembly line (PFAL) is a mixed model-assembly line, which is widely used in mass customization and intelligent manufacturing. The purpose of this paper is to…
Abstract
Purpose
The product family assembly line (PFAL) is a mixed model-assembly line, which is widely used in mass customization and intelligent manufacturing. The purpose of this paper is to study the problem of PFAL, a flexible (evolution) planning method to respond to product evolution for PFAL, to focus on product data analysis and evolution planning method.
Design/methodology/approach
The evolution balancing model for PFAL is established and an improved NSGA_II (INSGA_II) is proposed. From the perspective of data analysis, dynamic characteristics of PFAL are researched and analyzed. Especially the tasks, which stability is considered, can be divided into a platform and individual task. In INSGA_II algorithm, a new density selection and a decoding method based on sorting algorithms are proposed to compensate for the lack of traditional algorithms.
Findings
The effectiveness and feasibility of the method are validated by an example of PFAL evolution planning for a family of similar mechanical products. The optimized efficiency is significantly improved using INSGA_II proposed in this paper and the evolution planning model proposed has a stronger ability to respond to product evolution, which maximizes business performance over an effective period of time.
Originality/value
The assembly line designers and managers in discrete manufacturing companies can obtain an optimal solution for PFAL planning through the evolution planning model and INSGA-II proposed in this paper. Then, this planning model and optimization method have been successfully applied in the production of small wheel loaders.
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Fabrizio Salvador, Manus Rungtusanatham, Cipriano Forza and Alessio Trentin
This paper aims to investigate the factors enabling or hindering the simultaneous pursuit of volume flexibility and mix flexibility within a supply chain through the lens of a…
Abstract
Purpose
This paper aims to investigate the factors enabling or hindering the simultaneous pursuit of volume flexibility and mix flexibility within a supply chain through the lens of a manufacturing plant seeking to implement a build‐to‐order (BTO) strategy.
Design/methodology/approach
To accomplish this empirical investigation, an in‐depth case study involving a manufacturing plant and its supply chain was designed. Prior to primary and secondary data collection, this research setting had already decided to implement a BTO strategy and had, moreover, carefully assessed several practices for BTO strategy implementation, as well as their interactions.
Findings
The studied case suggests that a number of approaches typically used to increase volume flexibility, actually negatively affect mix flexibility and vice versa. The existence of such trade‐offs may ultimately inhibit the implementation of a BTO strategy and this was the case in the studied company. Nevertheless, empirical evidence also suggests that, to some extent, volume flexibility and mix flexibility may be achieved synergistically, as initiatives such as component standardization or component‐process interface standardization would improve both volume flexibility and mix flexibility.
Research limitations/implications
The pursuit of volume flexibility and mix flexibility in implementing a BTO strategy in a specific setting and from primarily an operations management perspective was investigated. As such, the findings can be complemented by viewing the case study results through the lens of other established general management theories or by replicating the study in different research settings.
Originality/value
While past research informs us about how manufacturing firms can successfully achieve mix flexibility or volume flexibility, there are few insights for understanding how volume flexibility and mix flexibility can both be simultaneously achieved within a manufacturing plant and its supply chain. This research fills this gap in the literature and contributes to the development of a theory of BTO strategy implementation, especially in terms of volume flexibility, mix flexibility and their interactions.
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Narges Asadi, Mats Jackson and Anders Fundin
The recent shift towards accommodating flexibility in manufacturing companies and the complexity resulting from product variety highlight the significance of flexible assembly…
Abstract
Purpose
The recent shift towards accommodating flexibility in manufacturing companies and the complexity resulting from product variety highlight the significance of flexible assembly systems and designing products for them. The purpose of this paper is to provide insight into the requirements of a flexible assembly system for product design from the assembly system’s standpoint.
Design/methodology/approach
To fulfil the purpose of the paper, a literature review and a case study were performed. The case study was conducted with an interactive research approach in a global market leader company within the heavy vehicle manufacturing industry.
Findings
The findings indicate that common assembly sequence, similar assembly interfaces, and common parts are the main requirements of a flexible assembly system for product design which reduce complexity and facilitate various flexibility dimensions. Accordingly, a model is proposed to broaden the understanding of these requirements from the assembly system’s standpoint.
Research limitations/implications
This study contributes to the overlapping research area of flexible assembly systems and product design.
Practical implications
The proposed model is largely based on practical data and clarifies the role of product design in facilitating flexibility in an assembly system. It can be used by assembly managers, assembly engineers, and product designers.
Originality/value
The key originality of this paper compared to the previous studies lies in presenting a novel assembly-oriented design model. The model enhances understanding of a flexible assembly system’s requirements for product design with regard to reducing complexity and managing variation in a flexible assembly system. These requirements can be applied to product design across various product families within a company’s product portfolio.
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Linda L. Zhang and Brian Rodrigues
The purpose of this paper is twofold. In view of the importance of process platform‐based production configuration (PPbPC) in sustaining product family production efficiency, it…
Abstract
Purpose
The purpose of this paper is twofold. In view of the importance of process platform‐based production configuration (PPbPC) in sustaining product family production efficiency, it is to study the underlying logic for configuring production processes for a product family based on a process platform. Second, it is to apply the Petri nets (PNs) techniques to model PPbPC, in attempting to shed light on the underlying logic.
Design/methodology/approach
The authors first identify the fundamental issues in PPbPC, including variety handling, process variation accommodation, configuration at different abstraction levels, and constraint satisfaction. To accommodate the corresponding modelling difficulties, the authors develop a formalism of hierarchical colored timed PNs (HCTPNs) based on the principles of hierarchical PNs, timed PNs, and colored PNs. In the formalism, three types of nets together with a system of HCTPNs are defined to address the modelling of PPbPC.
Findings
Applying HCTPNs to vibration motors' case has revealed the logic of specifying complete production processes of final products at different levels of abstraction to achieve production configuration. The preliminary results also further demonstrate the feasibility of modelling PPbPC based on HCTPNs.
Research limitations/implications
Traditional approaches to planning production processes for individual products may limit production performance improvement when companies need to timely produce a high variety of customized products. Systematic methods should be developed to plan production processes for product families so as to achieve production efficiency while utilizing the existing manufacturing resources.
Originality/value
By integrating the advantages of existing PN techniques, the HCTPNs formalism is developed to shed light on planning production processes for product families. The resulting production configuration model can facilitate practitioners to achieve production efficiency in producing large numbers of customized products.
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Anna Azzi, Daria Battini, Maurizio Faccio and Alessandro Persona
The purpose of this paper is to apply group assembly (GA) considerations to the construction industry and to provide evidence of construction sector industrialization with…
Abstract
Purpose
The purpose of this paper is to apply group assembly (GA) considerations to the construction industry and to provide evidence of construction sector industrialization with quantitative results. Moreover, a flexible assembly system is proposed, especially designed to cope with variability: this can be easily extendable to other industrial sectors, especially when dealing with extremely variable environments.
Design/methodology/approach
The paper presents a case study conducted at an Italian company leader in the design, manufacture and installation of architectural claddings and lightweight continuous facades.
Findings
The research empirically demonstrates how the application of GA and the creation of project families lead to consistent enhancement also within the construction industry. The case study reveals great improvement in terms of both operating and ergonomic performances, agile assembly system reconfiguration design and make span reduction. The possibility of correlating a new project to an identified family gives the opportunity to understand the best assembly line layout configuration which should be assigned to the project, to improve the throughput time and the controllability of the assembly process and to guarantee efficient floor space utilization, lead‐time control, accuracy and reliability.
Originality/value
The novelty of the study lies in the way the assembly layout is designed to cope with variability: the assembly line, which is dedicated to more stable processes, is coupled with pre‐assembly stations, easily reconfigurable, meant to be “variability absorbers”. As far as the authors know, this is also the first time GA is applied to the construction industry. Moreover, a timely topic such as construction sector industrialization is confirmed by quantitative results.
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Venkatesh Arasanipalai Raghavan, Sangwon Yoon and Krishnaswami Srihari
This paper aims to focus on integrating a lean framework in a high-mix-low-volume (HMLV) printed circuit board assembly (PCBA) environment to enhance current assembly processes…
Abstract
Purpose
This paper aims to focus on integrating a lean framework in a high-mix-low-volume (HMLV) printed circuit board assembly (PCBA) environment to enhance current assembly processes and facility layouts. An HMLV PCBA environment is characterized by stochastic demands, a variety of products in terms of shapes and sizes and different sequences of assembly and test operations, in addition to long cycle times and high fall-out rates.
Design/methodology/approach
Preliminary analysis indicates that the push inventory control system led to the longer cycle times, such that various lean methodologies have been applied to enhance the assembly operations. In this research, Kanban sizes for different assembly lines are also estimated to integrate and implement a “pull-system” into the lean framework. In addition, material movement and facility layout have been studied to minimize work-in-process travel time. An “iterative-MAIC” approach has been applied to implement lean principles.
Findings
As a result, a lean manufacturing pilot line has been implemented to evaluate the effectiveness of the lean principles before rolling them out across the manufacturing floor. It has been shown that the cycle times of the pilot line products are decreased by 40 per cent and the number of defects decreased by 10-30 per cent, depending on different assembly processes, after the lean implementation.
Originality/value
There is limited literature that addresses lean transformation in an HMLV electronics manufacturing service provider handling several product types with different testing methodologies, frequent product revision changes and higher fall-out rates. Hence, in this research, lean manufacturing has been implemented in an HMLV PCBA environment, which has the challenges of varying demand with a mix of assembly and test operations for different product families.
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Mary Weir and Jim Hughes
Introduction Consider a hi‐fi loudspeaker manufacturing company acquired on the brink of insolvency by an American multinational. The new owners discover with growing concern that…
Abstract
Introduction Consider a hi‐fi loudspeaker manufacturing company acquired on the brink of insolvency by an American multinational. The new owners discover with growing concern that the product range is obsolete, that manufacturing facilities are totally inadequate and that there is a complete absence of any real management substance or structure. They decide on the need to relocate urgently so as to provide continuity of supply at the very high — a market about to shrink at a rate unprecedented in its history.
This book is a policy proposal aimed at the democratic left. It is concerned with gradual but radical reform of the socio‐economic system. An integrated policy of industrial and…
Abstract
This book is a policy proposal aimed at the democratic left. It is concerned with gradual but radical reform of the socio‐economic system. An integrated policy of industrial and economic democracy, which centres around the establishment of a new sector of employee‐controlled enterprises, is presented. The proposal would retain the mix‐ed economy, but transform it into a much better “mixture”, with increased employee‐power in all sectors. While there is much of enduring value in our liberal western way of life, gross inequalities of wealth and power persist in our society.
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Linda L. Zhang, Qianli Xu and Petri Helo
The purpose of this paper is twofold. First, it is to introduce a knowledge‐based system for planning processes for families of final products, instead of component items, be they…
Abstract
Purpose
The purpose of this paper is twofold. First, it is to introduce a knowledge‐based system for planning processes for families of final products, instead of component items, be they parts or assemblies. Second, it is to demonstrate the feasibility and potential of a prototypical system developed for planning processes families for truck families from a multinational company.
Design/methodology/approach
The authors first identify the challenges in planning process families, including data and knowledge representation and constraint handling. To accommodate these challenges, the paper adopts the integrated product and process structure (IP2S) and colored timed Petri nets (CTPNs) in the proposed knowledge‐based process family planning system. On top of the IP2S and CTPNs, XML‐based knowledge representation is employed to alleviate the difficulties in modelling complex product and process family data and planning knowledge while enabling information exchange across different operating platforms. In addition, in accordance with the correspondence between PNs and knowledge‐based systems, a mechanism is designed to cope with the generation of production rules, which model constraints.
Findings
The proposed system is able to automatically generate production processes for customized products. At a higher level, such production processes provide input (e.g. operations, machines) to downstream activities for planning process details to manufacture component parts or component assemblies.
Research limitations/implications
Traditional trial and error approaches to planning processes limit production performance improvement when companies need to timely produce diverse customized products. Knowledge‐based systems should be developed to help companies better plan production processes based on the available manufacturing resources.
Originality/value
Unlike most reported studies addressing either detailed process planning or assembly planning for component parts or component assemblies, this study tackles process planning for final products, in attempting to maintain production efficiency from a holistic view.
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Narpat Ram Sangwa and Kuldip Singh Sangwan
This paper proposes an integrated value stream mapping (VSM) for a complex assembly line to improve the leanness of a complex automotive component manufacturing organization.
Abstract
Purpose
This paper proposes an integrated value stream mapping (VSM) for a complex assembly line to improve the leanness of a complex automotive component manufacturing organization.
Design/methodology/approach
This study depicts the application of VSM at the case organization, where top management is concerned about the challenges of higher cycle time and lower productivity. Gemba walks were conducted to establish the concept of “walk the flow, create the flow” along the assembly line. The multi-hierarchical cross-functional team developed the current value stream map to know the “as-is” state. Then, the team analysed the current VSM and proposed the future VSM for the “to-be” state.
Findings
The integrated VSM shows different processes and work cells, various wastes, non-value-added activities, cycle time, uptime and the material and information flows for both products of the assembly line on the same map. The integrated VSM reduced cycle time, non-value-added activities, work in process inventory and improved line efficiency and production per labour hour for both the products, simultaneously.
Research limitations/implications
The limitation of the study is that the study focussed only on the application of VSM for one complex assembly only. Future research may be conducted using the developed integrated VSM approach in other complex production environments.
Practical implications
Managers can identify and reduce system waste by incorporating the concept of integrated VSM in a complex production or assembly environment where two or more products are being manufactured/assembled with low similarity.
Originality/value
The application of VSM for assembly lines is highly challenging because of merging flows, a large number of child parts in the lines and assembly of more than one product on the same line.
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