Anoop Desai

Evaluation of disassemblability to enable design for disassembly in mass production

Abstract A comprehensive methodology to enhance disassemblability of products has been presented in this paper. Disassemblability of a product is a function of several parameters such as exertion of manual force for disassembly, degree of precision required for effective tool placement, weight, size, material and shape of components being disassembled, use of hand tools, etc. The study of relevant literature indicates the presence of disassembly evaluation criteria and methodologies that address the problem partially such as disassembly sequence planning or economic analysis. As far as design for disassembly is concerned, there is a plethora of literature on rules to improve recycling end-of-life components. A systematic methodology to incorporate disassembly considerations in product design and enable quantitative evaluation of the design is absent. The current methodology assigns time-based numeric indices to each design factor, which make for easy and quick determination of disassembly time. A higher score indicates anomalies in product design from the disassembly perspective. Addressing these anomalies can result in significant design modifications rendering an overall increase in disassemblability of the product. Decisions regarding design modifications are based on weighing several factors such as technical and economic feasibility, overall functionality and structural rigidity of the product as a whole. Relevance to industry A comprehensive Design for Disassembly methodology is developed which is intended to act as a tool in life cycle engineering.

Incorporating work factors in design for disassembly in product design

Purpose – This paper seeks to present a methodology to design products for disassembly. This would facilitate end‐of‐life product disassembly with a view to maximizing material usage in the supply chain at a low cost to the environment.Design/methodology/approach – The methodology presented in the paper draws on fundamentals related to task analysis and motion time measurement. The methodology was practically applied to disassemble several different consumer products with significant savings in time.Findings – Several improvements in product design resulted from various perspectives including functionality, assembly, aesthetics and disassembly.Research limitations/implications – The paper identifies several areas of future research including design optimization and designing work fixtures for disassembly.Originality/value – This work presents in part an improvement in current methodologies related to disassembly as well as original work based on task analysis and suggestion of design alternatives. The pap...

Design for maintenance: basic concepts and review of literature

This paper endeavours to present basic concepts and an outline of current research in the field of designing products/systems to enable ease of maintenance. The process of product maintenance is often a necessary evil since it ensures smooth performance of equipment, often at the cost of equipment downtime. Products that are easy to maintain entail less downtime. This means that they can be maintained at less expense, in less time and with less effort. There is a considerable amount of mathematical research conducted on this topic. Researchers have tended to focus on evolving mathematical models to predict maintenance schedules, downtime, etc. Much of that research is reactive in nature and is not useful as far as design is concerned. A methodology that enables product design for maintenance is conspicuous by its absence. This paper focuses on research efforts that can be directly helpful in the evolution of such a methodology.

Changing Trends in US Injury Profiles: Revisiting Non-Fatal Occupational Injury Statistics

The purpose of this paper is to review the current trends in non-fatal injury profiles of workers in the United States. It is generally accepted that occupational injury and illness rates are affected by many factors, such as the amount and quality of training, employee turnover rates, work experience, extent of mechanization and automation, job-related parameters, and worker gender. In the last decade, not only have the technologies used in the workplace changed significantly, there has been a greater awareness among employers and employees as to the importance of containing work injuries. Additionally, the extent of outsourcing for labor-intensive jobs has increased dramatically owing to cheaper labor costs in places such as China and Mexico. These changes have affected the manufacturing sector of US industry more than any other sector. How these changes have influenced the injury and illness profiles of the American worker is of considerable interest given the increased attention paid to work-workplace design, injury hazard control, and ergonomics in general. In this paper, we compare the injury and illness profiles of US workers separated by nearly a decade. The trends from early 1990s are compared to those from early 2000s. Data from the Bureau of Labor Statistics were used to compile the injury statistics. The results of our comparison show that while the absolute numbers of work-related injuries and illnesses have declined over the last 10 years, the basic trends associated with different factors remain almost unchanged. The reasons for this decline are discussed in this paper.

Simplifying the product maintenance process by building ease of maintenance into the design

A systematic methodology that seeks to enhance ease of maintenance of industrial equipment and machinery has been presented in this paper. The methodology relies heavily on methods time measurement (MTM) systems as well as makes extensive use of design for X principles to accomplish design modifications. It is well known that maintenance is often a necessary evil because it is responsible equipment downtime, but needs to be done anyway. The reason is that lack of regular maintenance often results in serious equipment failure. This can lead to a variety of consequences including quality problems, safety problems and most important of all lower productivity and increased product costs. The methodology presented in this paper deals with product design for maintenance. The one salient feature of this methodology is that it takes into account the labour-intensive nature of the maintenance operation in general and incorporates appropriate ergonomic factors to reflect this consideration. MTM principles are used in order to impart a degree of objectivity to the methodology in terms of time evaluation. The relationship between maintenance time and product design characteristics is also established. This paper can be distinctly divided into two sections. The first part introduces the reader to some important maintenance-related concepts. The second part of this paper presents the aforementioned methodology. A real-life case study using an actual consumer product is also used towards the end of this paper to help corroborate the practical value of the methodology.

Chapter 7 – Designing for Assembly and Disassembly

Publisher Summary A product more often than not is the assemblage of various individual components. The spatial alignment between functionally important components is what makes the product function. This chapter emphasizes the importance of designing for ease of assembly and disassembly. Assembly of a product is a function of design parameters that are both intensive (material properties) and extensive (physical attributes) in nature. Its design parameters include shape, size, material compatibility, flexibility, and thermal conductivity. When individual components are manufactured with ease of assembly in mind, the result is a significant reduction in assembly lead times and savings in resources (both material and human). It is imperative that each component be designed in such as way as to align efficiently. This entails the design and processing of the component in a specific manner with respect to shape, size, tolerances, and surface finish. On the other hand, disassembly is the organized process of taking apart a systematically assembled product to enable maintenance, enhance serviceability, and/or to affect end of life objectives, such as product reuse, remanufacture, and recycling. It is not necessarily the opposite of assembly. Components need to be designed for disassembly so that the process can be effected without damage to the parts’ intensive and extensive properties. Its importance can be attributed to growing scarcity of natural resources, increased processing costs for virgin materials (such as mining iron ore for steel manufacturing), and environmental legislation to make manufacturers more responsible with regard to waste disposal.

Human impediments to technology transfer

The transfer of technology is a multifaceted and complex issue. The adoption of advanced technologies is essential from the perspective of the strength of national economies and enhancing international competitiveness. Transfer of technology can be realised by transferring knowledge and through its commercialisation. Numerous impediments hinder the successful and effective transfer of technology. The most crucial role is played by human related impediments. Given the equality of other factors such as technological availability, capital, availability of resources etc., the adaptability of human resources may in most cases be the deciding factor so far as successful adoption of advanced technologies is concerned. In the first part, this paper examines the general obstacles faced by importers and exporters of technology. The role played by training in overcoming the human aspect of technology transfer has been emphasised in the second part.

Chapter 10 – Design for Usability

Publisher Summary n an increasingly competitive world, design lead time is on a continuous decline in an ever increasing push to get new products to market quicker. This means that the onus is now on the manufacturer to develop a highly usable product right the first time. The process of designing and manufacturing consumer products is influenced greatly by the needs and demands of the customers. This chapter provides an introduction to the concept of design for usability and suggests measures aimed at product usability. The checklist-based approach provides a heuristic method to tell designers what to expect in a product to adopt the most appropriate design and relate manufacturing processes to user requirements. Case studies and questionnaires are developed and tested for usability dimensions. The practical implication of the overall usability score is that it can be used as a criterion for product selection. The score does not study the influence such measures have on product cost. In this day and age, products need to be made usable by making them environmentally friendly, emphasizing energy efficiency, recyclability, and disposability. Therefore, all life-cycle phases of a product need to be considered simultaneously in determining the usability: design, production, distribution, usage, maintenance, and disposal/recycling.

Designing for Assembly and Disassembly

A product more often than not is the assemblage of various individual components. The spatial alignment between functionally important components is what makes the product function. This chapter emphasizes the importance of designing for ease of assembly and disassembly. Assembly of a product is a function of design parameters that are both intensive (material properties) and extensive (physical attributes) in nature. Its design parameters include shape, size, material compatibility, flexibility, and thermal conductivity. When individual components are manufactured with ease of assembly in mind, the result is a significant reduction in assembly lead times and savings in resources (both material and human). It is imperative that each component be designed in such as way as to align efficiently. This entails the design and processing of the component in a specific manner with respect to shape, size, tolerances, and surface finish. On the other hand, disassembly is the organized process of taking apart a systematically assembled product to enable maintenance, enhance serviceability, and/or to affect end of life objectives, such as product reuse, remanufacture, and recycling. It is not necessarily the opposite of assembly. Components need to be designed for disassembly so that the process can be effected without damage to the parts’ intensive and extensive properties. Its importance can be attributed to growing scarcity of natural resources, increased processing costs for virgin materials (such as mining iron ore for steel manufacturing), and environmental legislation to make manufacturers more responsible with regard to waste disposal.

The cost of not training

The success of transferred technology may be measured by working effectiveness and proficiency that are achieved in the end. Training plays a key role in the effective integration of transferred technology in the workplace and enhancing productivity. Some form of periodic training or retraining is generally available in most organisations to ensure that employees continue to perform at the anticipated and desired levels. The presence or implementation of training alone, however, cannot guarantee increased profitability. It is necessary that good objectives and teaching methods be applied along with a sound training implementation plan. Periodic assessment of training results and corresponding modifications of training must also be put into action simultaneously. This paper emphasises those aspects of training, which, when absent, affect the organisation as a whole. It analyses the process of training and in doing so sheds light on what an organisation is deficient in when its human resource lacks training and/or employs improper training techniques.