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The purpose of this paper is to uncover the significance of quick changeovers in die‐casting foundry environments.

The paper gives set‐up instructions and guidelines to prepare the standardized set‐up procedure without ignoring actual constraints in foundries. It uses a case study in a medium scale piston foundry to generate an integrated set‐up reduction approach, utilizing single minute exchange of die (SMED)‐based industrial engineering tools to achieve faster set‐ups. It describes the feasibility of quick changeovers in foundry small and medium enterprises based on a “SMED” approach. Finally, the paper carries out empirical analysis of the financial/non‐financial benefits incurred from set‐up reductions.

Set‐up activities are a vital part of the production lead‐time of any product and so affect overall product cost. Tools like Pareto analysis, root‐cause analysis and method study have been used to analyze the existing procedure of set‐ups. A SMED approach can help eliminate unwanted activities, externalize the internal activities, if possible and reduce them by simplification or standardization. The application of other tools such as 5S, Poke‐Yoke and specific tool‐kits are suggested to further reduce set‐up times.

The paper demonstrates the practical application of SMED showing how it can bring real breakthroughs in productivity to small and medium scale foundries.

Procedures to reduce set‐up times at individual machines have been well documented; however, very little research has been conducted on developing an effective strategy to prioritize set‐up reduction procedures in a multi‐machine facility. Describes a new and innovative way – a throughput approach – to prioritize set‐up reduction procedures in a multi‐machine production system.

Cell formation design in cellular manufacturing systems (CMS) has been the focus of recent manufacturing research literature. A great amount of research has been published addressing either technical issues (e.g. part‐machine grouping algorithms) or operational issues (e.g. planning and scheduling in the CMS). Research addressing strategic issues in cell formation design has been minimal. Addresses strategic considerations in cell formation design, specifically, the linkage and relationships between specific cell design issues and the firm′s competitive advantage in the marketplace. It is demonstrated that cell formation design decisions must be addressed in alignment with the firm′s strategic plan and manufacturing competitive priorities.

The Japanese approach to manufacturing has been well documented. Many European firms have successfully adopted and adapted a variety of Japanese manufacturing techniques. This paper describes how a pharmaceutical manufacturer responded to an increased requirement for manufacturing flexibility through the introduction of a key Japanese manufacturing technique, namely machine set‐up time reduction. An unusual feature of the study is the use of action research. The strong emphasis on participation and collaboration inherent in action research, was felt to make it appropriate to tackling the company’s capacity problem. Not only were set‐up times substantially reduced, but action research demonstrated the value of all staff being involved in the problem‐solving process.

Simulation experiment was employed to investigate the schemes for coordinating JIT practices to promote performance upgrade in a job shop environment with the pull system.

The four related essential JIT practices (job shop JIT practices) investigated include: cellular manufacturing (CM), operations overlapping (OPOVR), reduction of set‐up/processing time variability (variability reduction) and set‐up time reduction (STR).

Experiment findings suggest that coordination of CM and STR should be given the priority. While the extent of STR effected by CM substantially influences the efficacy of adopting a cellular layout, the choice of adopting a functional layout (FL) is more likely to be affected by the STR resulted from improvement of set‐up operations (set‐up improvement). Variability reduction tends to be more effective for a cellular layout. For a cellular layout without OPOVR, the effectiveness of reducing set‐up time variability is prominent and almost impervious to the extent of set‐up improvement. For a FL, the effect of variability reduction is minor; reduction of set‐up time variability is effective in this case only for a set‐up to processing time ratio of 20 or larger. The findings of this study do not justify the implementation of OPOVR in the shop environment, even with the support of the other three job shop JIT practices.

This study is notable in integrating STR into the job shop JIT practices to achieve overall performance improvement. In addition, the resulting strategies for variability reduction are essential for adapting the pull system to job shop manufacturing. Therefore, the findings of this study form systematic guidelines enabling exercise of the job shop JIT practices coherently to promote reform of job shop manufacturing.

This paper presents Quick Changeover Design (QCD), which is a structured methodological approach for Original Equipment Manufacturers to drive and support the design of machines in terms of rapid changeover capability.

To improve the performance in terms of set up time, QCD addresses machine design from a single-minute digit exchange of die (SMED). Although conceived to aid the design of completely new machines, QCD can be adapted to support for simple design upgrades on pre-existing machines. The QCD is structured in three consecutive steps, each supported by specific tools and analysis forms to facilitate and better structure the designers' activities.

QCD helps equipment manufacturers to understand the current and future needs of the manufacturers' customers to: (1) anticipate the requirements for new and different set-up process; (2) prioritize the possible technical solutions; (3) build machines and equipment that are easy and fast to set-up under variable contexts. When applied to a production system consisting of machines subject to frequent or time-consuming set-up processes, QCD enhances both responsiveness to external market demands and internal control of factory operations.

The QCD approach is a support system for the development of completely new machines and is also particularly effective in upgrading existing ones. QCD's practical application is demonstrated using a case study concerning a vertical spindle machine.

Contrasts functional layouts and cellular layouts with regard to the effects of set‐up time reduction and lot size on flow time and through‐put. The structural environment for the functional analysis is an efficient functional system with a staged sequence of four machine centers with unidirectional flow and no backtracking. The structural environment for the cellular analysis is a partitioned cell consisting of one machine from each of the four machine types with unidirectional flow and no backtracking. Simulation models produce robust results for eight lot size levels and one (functional model) and seven (cellular model) set‐up time reduction levels. The results contrast the effectiveness of the two manufacturing approaches under differing input conditions. Shows that the choice between the functional structure and the cellular structure significantly affects through‐put at lot sizes up to 55, while for lot sizes of 60 and above there is no significant effect. The study also confirms previous results regarding the effect of manufacturing structure choice on flow time.

There is considerable interest in the Just‐in‐Time production method and the potential benefits that can be realised, particularly in a reduction in the work‐in‐progress inventory. The article reviews some of the salient prerequisites necessary for successful implementation of the JIT system. Two major factors are examined using a simulation model. Results indicated that contrary to widespread conjecture it is not necessary to maintain a balance in the process times between work stations. With the choice of a suitable scheduling rule, such as SPT/LATE, the system performance can be superior to that for constant process times. It is also found that the pull system is relatively unresponsive to a heavy imposed loading and process utilisation is generally low. Finally, smaller batches give better system effectiveness but the improvement is less significant than for the conventional push system.

Proposes a virtual cellular manufacturing approach to implementing cellular manufacturing systems that combines the set‐up efficiency typically obtained by traditional cellular manufacturing or group technology systems with the flexibility of a job shop. Unlike traditional cellular systems in which the shop is physically designed as a series of cells, cells are formed within a shop utilizing a process layout using scheduling mechanisms. The result is the formation of cells that are temporary and logical (virtual) in nature, allowing them to be more responsive to changes in demand patterns. Simulation runs comparing this approach to production using traditional cellular and job shop approaches indicate that this new approach yields significantly better shop performance over a range of operating conditions.

THE study of fatigue from a physiological aspect is a field which motion study technicians have made little or no attempt to explore. Shame on their heads. The physiological simplification of motions aimed at reducing fatigue could have completely offset the notion that motion study is aimed at converting the operator into an automaton. It may well be that an elaborate motion pattern set‐up designed to simplify the work merely succeeds in setting up stresses in the worker. The superimposing of a time‐studied standard for the job may not have taken into account the adaptation of the speed of motions to the physiological limitations of the operator working at a high level performance. Very few practitioners have attempted to study motions in the factory with a view to reducing fatigue and stress as a prerequisite to studying the set‐up for increased production. Still fewer have attempted to evaluate these factors. It is about time they did.