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The purpose of this paper is to determine how kitting, compared to continuous supply, affects the time spent by the assembler fetching parts in manual assembly.

The paper is based on an experimental setup at the Saab Automobile assembly plant in Trollhättan, Sweden. Experienced assemblers were studied as they performed the same assembly operations in ten different configurations. Each configuration consisted of a different arrangement in terms of how parts were presented. The use of kits to present parts was compared to parts presentation through continuous supply, where each part number was presented in a separate container.

The time for fetching parts is significantly shorter when parts are presented through kitting instead of through continuous supply. Furthermore, the shorter fetching time is not just related to a shorter distance between assembly object and parts presentation, which can often be achieved through kitting. The reduction of time spent searching for parts is also considerable.

The results of the paper provide valuable input in the design of assembly and materials supply systems, as they enable a better understanding of the relative performance of the materials feeding principles of kitting and continuous supply.

Previous studies of kitting and its impact on assembly are mostly conceptual or qualitative, whereas quantitative studies are scarce. The current paper provides a substantial contribution by quantifying the effects that kitting, compared to continuous supply, has on the time spent fetching parts.

The purpose of this paper is to provide an understanding of how the materials feeding design at a workstation impacts the assembly process performance, in terms of manufacturing flexibility, process support, materials planning and work task efficiency.

The empirical data are based on two embedded case studies performed in close corporation with two Swedish automotive companies; additional observations from more than 20 company visits in Japan, and small‐scale case studies performed in Japanese companies. To fully assess the work measurement figures, video recordings, work instructions and layout drawings were used to plot the operators' walking patterns, and it was then possible to map the whole work cycle for an operator. Industrial engineers, managers, group leaders, team leaders and operators were interviewed. Based on the literature review and personal experience from the small‐scale case studies carried out in Japan, the existing assembly systems' component racks were conceptually re‐designed. This led to two hypothetical assembly systems, which could be used for understanding the impact of materials feeding design on assembly process performance. The design of the new component racks and the choice of packaging types were made together with practitioners.

The paper shows that the design of component racks and choice of packaging types have a major impact on the assembly process performance. Component racks with a large depth and small width and tailored packages create important advantages over traditional Swedish component racks designed for EUR‐pallets. Line stocking is not always the best choice for materials feeding, but this paper shows that line stocking, especially in Swedish assembly systems, can be improved. Sequencing can thus be reduced, resulting in fewer problems when there are sequence breaks in the production flow. Component racks with small packages and large depth increase the work task efficiency, volume, mix, new products and modification flexibility. For example, free space is an important issue for these types of flexibilities. Component racks that are portable and easy to rearrange, together with free space, greatly facilitate handling of new product introductions or modifications of products. The new and old component can be displayed and fed to the same workstation, and if there is a larger change a whole segment of a component rack can easily be replaced by a new one between work shifts.

The scope of the study is limited to the conditions at workstations. Consequences for the materials flow upstream (i.e. internal materials handling, warehousing, transport, supplier processes, etc.) are not included, but must in further studies also be considered to avoid sub‐optimisation.

The paper highlights the fact that a shift in focus is necessary when designing workstations with component racks in Swedish companies, meaning that operators become the customers rather than the transport company or materials handler.

Reports results from research collaboration between university and industry from the last six years (1985‐91) intensive work on the development of the radically new production concepts in use today in Volvo Car Corporation′s Uddevalla plant. Important breakthroughs in knowledge have been realized, including a product description adapted to assembly, new material supply systems and layouts for final assembly. This product description allowed performance to be determined for alternative production concepts. It is also a basic precondition for maintaining a logic in how the material is displayed and assembly work described, and is therefore formalized, principally through material supply systems, information systems and final assembly layouts. Emphasizes that efficient long cycle assembly work and flexible manufacturing assume both completely new preconditions on the shopfloor and a new management form. Makes clear, however, that these pre‐conditions demand a basically untraditional way of reasoning.

In recent years, assembly lines have been reintroduced in the Swedish automotive industry and, in many cases, have replaced those so‐called alternative assembly systems which had their roots in the 1970s. This paper reviews and evaluates some explicit reasons given for the return to the assembly line. It also considers whether the decisions to replace alternative assembly systems with assembly lines may have been driven by other factors and mechanisms than those implicit in these arguments and, if so, what other factors could explain their reintroduction. There is also a discussion of which dimensions that should be taken into account when choosing between alternative assembly systems and assembly lines and empirical data are used to shed more light on the issues discussed in the article. The authors report one study that compares automobile assembly in an alternative assembly system with assembly of the same products after introducing an assembly line. They also briefly discuss reasons for and experiences from the recent introduction of alternative assembly systems in the Japanese electronics industry. In this case, so‐called cellular assembly systems have replaced assembly lines.

The purpose of this paper is to determine whether man-hour efficiency of picking is affected by the use of batch preparation, compared to preparation of one kit at a time. This paper focuses on small kit preparation areas.

This paper is based on two experiments that were performed at a vehicle assembly plant and then analysed quantitatively.

The results provide a strong indication of the advantages associated with batch preparation, in terms of man-hour efficiency.

The fact that the effects identified during the experiments are substantial, over 20 per cent reduction of average time per picked component in Experiment 1 and 7 per cent in Experiment 2, indicates that the option of batch picking holds potentials for large cost reduction and should be considered when kit preparation systems are designed.

Limited research has dealt with the design of kit preparation systems, thus leaving considerable knowledge gaps. Previous research dealing with batch picking focuses on other environments than kitting and on large picking areas where batching can reduce walking distances. In contrast, the current paper focuses on small picking areas, which are common in industrial kitting applications. This paper provides a considerable contribution by demonstrating improvements in time efficiency that batch preparation can offer to small picking areas in addition to larger areas. The discussion also provides a basis for future research, which could focus on aspects other than time efficiency, such as the quality of kit preparation, and variables that might moderate the effect of batching.

Presents some theoretical principles and empirical evidence relating to the new Swedish production systems for final assembly of motor vehicles. Contends that in these production systems it is possible simultaneously to enhance efficiency and quality of working life. Briefly sketches three production forms as they apply to the final assembly of automobiles and discusses the societal environments in which these different forms of production have evolved. Focuses on Volvo′s Swedish Uddevalla plant as one of the main examples so far of a reflective production system for final assembly of automobiles. Amplifies the analysis of different production flow patterns for final assembly and in particular addresses the issue of semi‐parallel mechanistic production flow and parallel organic production flow as alternatives to serial flow on a conventional line assembly.

There is an increasing focus on reducing time‐to‐market for new products and a prerequisite for succeeding in this is the ability to transfer and use information about the products early on in projects, thus facilitating early problem‐solving. This paper focuses on the use of product data and information systems for the design of materials supply systems in product development projects. The results from a case study show that there are product data available at an early stage in the project. However, the product data have to be retrieved from several information systems and from information systems, which the materials supply systems designers cannot use. In addition, product data can be obtained by means of personal communication much earlier than they can be retrieved from the information systems. It is concluded that research and development is required so that the information systems can be utilised for both early release and retrieval of preliminary information.

Discusses production models for final assembly in the automotive industry and also reports on the performance of one final assembly plant representing an innovative production model, namely the Volvo Uddevalla plant. Briefly considers some issues and pitfalls in current production model discourse, and in this connection introduces a distinction between two manufacturing models and broader industrial models. Describes two manufacturing models for final assembly work as namely the “serial flow model” and the “parallel flow model”. Discusses the Japanese “lean production”, sometimes synonymous with “Toyotism”, as an industrial model and the impact of socio‐economic and socio‐cultural contexts on manufacturing models and industrial models. Concludes that the Uddevalla plant highlights the paradox that long cycle time work in parallel flow assembly systems is in fact more efficient than short cycle time work in serial flow systems, provided that suitable technical and administrative preconditions exist. Therefore, the engineering point of view and the Swedish experiences of innovative manufacturing systems should be carefully considered in the current production model discourse.

Presents a methodology useful when analysing the efficiency of order picking systems. The main feature of the analysis is the ability to compare different system designs. The methodology has earlier been applied mainly to assembly production systems, and has in these cases proved to be an effective management tool in discussions concerning the choice of production system.

Discusses experiences from the design of parallellized flow assembly systems. Also discusses factors influencing the performance of collective work and relates these to the flow parameters in the Saab Automobile′s final assembly plant in Malmö and the Volvo Uddevalla final assembly plant. Illustrates this discussion by empirical data from the shopfloor of the Volvo Uddevalla plant. Focuses mainly on the evolution of the intra‐group work pattern from the start in the training workshop to the final intra‐group work pattern and the assembly performance achieved before the closing down of the plant. Reports on management′s initial design assumptions communicated during the design of the Uddevalla plant. Comments on and revises these design assumptions, since they were far too simple and lacked the support of theoretical analysis and empirical evidence. The lack of a scientific explanation for the production and work organization principles communicated within Volvo might be one of the reasons for the closing down – it certainly was not the performance of the plant.