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The purpose of this paper is to illustrate the successful application of Six Sigma at a small and medium scale plastic parts manufacturing unit. Overall operational excellence is one of the foundations of global competiveness. Indian industries are also keeping up with achieving and maintaining operational excellence through different improvement tools and methodologies. Plastic parts manufacturing industries in India are also on the move to increase their overall quality, productivity and profitability. However, it appears from the available literature that application of Six Sigma, one of the most effective breakthrough improvement strategies having direct impact on bottom line of the organization, is not being explored to its full potential, especially at plastic parts manufacturing industries in India. This study was thus undertaken at plastic products manufacturing plant to introduce Six Sigma to them by applying the same to their chronic problems and drawing improvements in quality, productivity and profitability.

This paper illustrates the real-life case study of improving quality and productivity of injection molding process by phase wiz application of define, measure, analyze, improve and control, the process improvement methodology of Six Sigma.

The critical defects, such as short molding, contamination, injection point and flash are reduced from the process leading to annual savings of INR 10.80 lacs. This is a considerable amount for a small concern in question.

Because this was the pilot project and the firm was of small and medium size, data collection was the major issue, which consequently took considerable time and efforts at define and measure phases. Injection molding is a very salient process for plastic products manufacturing. Almost one-third of plastic products are made by this process. Thus, improving quality of products made out of injection molding process is of paramount importance. The paper is an attempt to exhibit how a small-scale plastic injection molded parts manufacturing unit can put fruitful efforts to achieve competitive advantage through Six Sigma.

From the review of literature, it appears that application of Six Sigma among plastic parts manufacturing units, especially small and medium, is very rare, not in India but across the globe. This case study has opened up the direction to small- and medium-scale plastic parts manufacturing units to implement Six Sigma and to move a step forward toward achieving competitive advantage.

The study aims to improve the understanding of the online sustainability disclosure phenomena considering the quantity and nature of the content of the information related to sustainability disclosed in the corporate website of companies, providing evidence about the website sustainability disclosure of different size companies and characterizing the website sustainability disclosure of the Portuguese mold companies.

A content analysis methodology was used to the corporate websites of 83 companies in the sample. A direct approach was followed where the researcher is asked to read and classify the text in a previously defined category, but where the possibility of identifying new categories from the collected data is not excluded.

The information on sustainability disclosed by the mold companies is limited, whether in quantity or concerning the type of information. The information disclosed about environmental and social aspects is scarcer, being the focus more on aspects related to the economic dimension of sustainability, particularly in the areas related to products and services and customers.

The research design can be broadened to include other sustainability dissemination tools and other research methodologies, such as case studies, to provide a deeper understanding of the concerns and initiatives/practices of sustainability of mold companies.

This study contributes to the knowledge of sustainability dissemination practices in SMEs, an area of research that needs to be more explored and, in an industrial sector (molds) that have not received much attention in this area.

Based on the premise of the importance of corporate sustainability communication, the study focuses on the Internet as an information dissemination tool. It provides indications on the theme and information type that can be used to report the company's sustainability.

In recent years, there has been a growing importance of sustainability communication and the role of the Internet in contemporary corporate communication that has allowed the diversification of information dissemination tools. Thus, the objective of this study is to determine the quantity and nature of the content of the information related to sustainability disclosed through the corporate website of Portuguese metal mould companies. The results obtained based on the content analysis seem to indicate that the number of metal mould companies that discloses sustainability information is quite low. Those who disclose information are in a very limited way whether in quantity or in relation to the type of information disclosed. Considering the various dimensions of sustainability, the information disclosed about environmental and social aspects is scarce. The focus is on aspects related to the economic dimension, particularly in the areas related to products and services and customers.

This study provides an up-to-date review of additive manufacturing (AM) technologies and guidance for selecting the most appropriate ones for specific applications, taking into account the main features, strengths, and limitations of the existing options.

A literature review on AM technologies was conducted to assess the current state-of-the-art. This was followed by a closer examination of different AM machines to gain a deeper insight into their main features and operational characteristics. The conclusions and data gathered were used to formulate a classification and decision-support framework.

The findings indicate the building blocks of the selection process for AM technologies. Furthermore, this work shows the suitability of the existing AM technologies for specific cases and points to opportunities for technological and decision-support improvements. Lastly, more standardization in AM would be beneficial for future research.

The proposed framework offers valuable support for decision-makers to select the most suitable AM technologies, as demonstrated through practical examples of its utilization. In addition, it can help researchers identify the limitations of AM by pinpointing applications where existing technologies fail to meet the requirements.

The study offers a novel classification and decision-support framework for selecting AM technologies, incorporating machine characteristics, process features, physical properties of printed parts, and costs as key features to evaluate the potential of AM. Additionally, it provides a deeper understanding of these features as well as the potential opportunities for AM and its impact on various industries.

In the last decade, cloud manufacturing (CMfg) has attracted considerable attention from academia and industry worldwide. It is widely accepted that the design and analysis of cloud manufacturing architecture (CMfg-A) are the basis for developing and applying CMfg systems. However, in existing studies, analysis of the status, development process and internal characteristics of CMfg-A is lacking, hindering an understanding of the research hotspots and development trends of CMfg-A. Meanwhile, effective guidance is lacking on the construction of superior CMfg-As. The purpose of this paper is to review the relevant research on CMfg-A via identification of the main layers, elements, relationships, structure and functions of CMfg-A to provide valuable information to scholars and practitioners for further research on key CMfg-A technologies and the construction of CMfg systems with superior performance.

This study systematically reviews the relevant research on CMfg-A across transformation process to internal characteristics by integrating quantitative and qualitative methods. First, the split and reorganization method is used to recognize the main layers of CMfg-A. Then, the transformation process of six main layers is analysed through retrospective analysis, and the similarities and differences in CMfg-A are obtained. Subsequently, based on systematic theory, the elements, relationships, structure and functions of CMfg-A are inductively studied. A 3D printing architecture design case is conducted to discuss the weakness of the previous architecture and demonstrate how to improve it. Finally, the primary current trends and future opportunities are presented.

By analyzing the transformation process of CMfg-A, this study finds that CMfg-A resources are developing from tangible resources into intangible resources and intelligent resources. CMfg-A technology is developing from traditional cloud computing-based technology towards advanced manufacturing technology, and CMfg-A application scope is gradually expanding from traditional manufacturing industry to emerging manufacturing industry. In addition, by analyzing the elements, relationships, structure and functions of CMfg-A, this study finds that CMfg-A is undergoing a new generation of transformation, with trends of integrated development, intelligent development, innovative development and green development. Case study shows that the analysis of the development trend and internal characteristics of the architecture facilitates the design of a more effective architecture.

This paper predominantly focuses on journal articles and some key conference papers published in English and Chinese. The reason for considering Chinese articles is that CMfg was proposed by the Chinese and a lot of Chinese CMfg-A articles have been published in recent years. CMfg is suitable for the development of China’s manufacturing industry because of China’s intelligent manufacturing environment. It is believed that this research has reached a reliable comprehensiveness that can help scholars and practitioners establish new research directions and evaluate their work in CMfg-A.

Prior studies ignore the identification and analysis of development process and internal characteristics for the current development of CMfg-A, including the main layers identification of different CMfg-As and the transformation process analysis of these main layers, and in-depth analysis of the inner essence of CMfg-A (such as its elements, relationships, structure and functions). This study addresses these limitations and provides a comprehensive literature review.

Digital twin (DT) is an emerging technology that enables sophisticated interaction between physical objects and their virtual replicas. Although DT has recently gained significant attraction in both industry and academia, there is no systematic understanding of DT from its development history to its different concepts and applications in disparate disciplines. The majority of DT literature focuses on the conceptual development of DT frameworks for a specific implementation area. Hence, this paper provides a state-of-the-art review of DT history, different definitions and models, and six types of key enabling technologies. The review also provides a comprehensive survey of DT applications from two perspectives: (1) applications in four product-lifecycle phases, i.e. product design, manufacturing, operation and maintenance, and recycling and (2) applications in four categorized engineering fields, including aerospace engineering, tunneling and underground engineering, wind engineering and Internet of things (IoT) applications. DT frameworks, characteristic components, key technologies and specific applications are extracted for each DT category in this paper. A comprehensive survey of the DT references reveals the following findings: (1) The majority of existing DT models only involve one-way data transfer from physical entities to virtual models and (2) There is a lack of consideration of the environmental coupling, which results in the inaccurate representation of the virtual components in existing DT models. Thus, this paper highlights the role of environmental factor in DT enabling technologies and in categorized engineering applications. In addition, the review discusses the key challenges and provides future work for constructing DTs of complex engineering systems.

The aim of this paper is to identify some specificities of production planning and control (PPC) activities in the one-of-a-kind-production (OKP) process through an extensive literature review. Relevant aspects related to systems and PPC activities in the context of OKP environment are discussed, and six opportunities for future research are highlighted.

The following research is based on a review of 53 articles published in peer-reviewed journals over the past three decades. After an initial descriptive analysis based on bibliometric indicators, a cluster analysis of 15 most cited articles was carried out using multivariate data analysis techniques and in-depth analysis.

The results reveal some specificities inherent to the clusters featured in the research, including aspects of planning, control and systems for OKP process. This cluster addresses information regarding next-generation manufacturing systems, scheduling and design science, computer simulation and project approach. On the other hand, the authors point out six topics for future research regarding contemporary issues associated with PPC in the context of OKP.

This paper fills an important gap regarding OKP production planning and control practices. The results provide a theoretical overview of different PPC practices suitable for the OKP environment. Furthermore, it can provide insights for scientific developments in order to manage the complexity inherent in the OKP process.

The purpose of this paper is to report a review of various perspectives of lean in heavy engineering and fabrication industries and to propose a framework.

Lean manufacturing (LM) earlier known as Toyota Production System (TPS) was mainly used by automobile industries where the operations occur in sequence and the adoption of LM was easier. When it comes to heavy engineering industries, the concept of lean can be adopted in a versatile operating environment to have more advantages by waste elimination thereby having higher profit. Thus, an effort is made to consolidate various lean perspectives, namely, barriers, principles, tools and performance measures and a framework was proposed on how various lean perspectives can be adopted in a systematic way.

A comprehensive analysis of lean from various perspectives from viewpoint of the fabrication industry are done and the review is presented. Also, the framework linking barriers, principles, tools and performance measures is being contributed as an outcome of the review.

The review of lean from various perspectives for the fabrication industry and the development of a framework is the original contribution of the authors.

The purpose of this paper is to evaluate the effect of post process combinations, e.g. hot isostatic pressing (HIP) only, HIP + T6 heat treatments, and T6 only, with different aging time, on surface properties, microstructure and mechanical properties of stress-relieved AlSi10Mg parts produced by direct laser metal sintering.

HIP process and HIP + T6 heat treatments were applied to as stress-relieved direct laser metal sintered (DMLS) AlSi10Mg parts. Aging times of 4 and 12 h are selected to examine the optimum duration. To analyze the advantages of HIP process, a T6 heat treatment with 4 h of aging was also applied. Densities, open porosities and roughness values of as stress-relieved, HIPed, HIP + T6, and T6-only samples were measured. The samples were characterized by OM and SEM together with EDX analysis. An image analysis study was made to evaluate the inner pore structure, thereby to understand the mechanical behavior.

HIP process does not cause a significant change in surface porosity; yet it has a positive influence on inner porosity. HIP process results in a microstructure of the aluminum matrix surrounded by a network of micron and nano size Si particles. Additional heat treatment results in larger particles and precipitation. After HIPing, ductility increases but strength decreases. Samples aged 4 h present improved yield and tensile strength but decreased elongation, yet samples aged for 12 h reach a combination of optimum strength and ductility. The lower level of tensile strength and ductility in T6-only condition indicates that HIP process plays a crucial role in elimination of the porosity thus improves the effectiveness of subsequent heat treatment.

The study investigates the effect of post-process conditions and optimizes the aging time of the T6 heat treatment after HIP process in order to obtain improved mechanical properties. The stress-relieved state was chosen as the reference to prevent distortion during HIPing or heat treatment.

Rapid tooling (RT) integrated with additive manufacturing technologies have been implemented in various sectors of the RT industry in recent years with various kinds of prototype applications, especially in the development of new products. The purpose of this study is to analyze the current application trends of RT techniques in producing hybrid mold inserts.

The direct and indirect RT techniques discussed in this paper are aimed at developing a hybrid mold insert using metal epoxy composite (MEC) in increasing the speed of tooling development and performance. An extensive review of the suitable development approach of hybrid mold inserts, material preparation and filler effect on physical and mechanical properties has been conducted.

Latest research studies indicate that it is possible to develop a hybrid material through the combination of different shapes/sizes of filler particles and it is expected to improve the compressive strength, thermal conductivity and consequently increasing the hybrid mold performance (cooling time and a number of molding cycles).

The number of research studies on RT for hybrid mold inserts is still lacking as compared to research studies on conventional manufacturing technology. One of the significant limitations is on the ways to improve physical and mechanical properties due to the limited type, size and shape of materials that are currently available.

This review presents the related information and highlights the current gaps related to this field of study. In addition, it appraises the new formulation of MEC materials for the hybrid mold inserts in injection molding application and RT for non-metal products.