A graph-based model for manufacturing complexity

This paper presents a graph-based model to measure the relative manufacturing complexity of and the manufacturing similarity of products in job shop manufacturing systems. This model depicts the impact of the complexity factors on the profit realisable from products based on their manufacturing process and required resources/skills. These resources deal with the process required for a component to reach assembly, the process of assembling the components to a whole product. This relative manufacturing complexity measure not only can support assembly and production cost estimation, but also can provide a guideline for creating a product with the most effective balance of manufacturing and assembly. Also, the results of this study can help improve budgeting and resource allocation, and the product life cycle cost estimation for future products. A numerical example is also presented to demonstrate the application of the proposed approach.     

Cycle time estimation models for printed circuit board design

Competitive pressures force the electronics industry, like many other industries, to keep costs down and reduce the duration of the development cycle time for products. The pressures affect all the phases of product development and direct attention to new approaches for planning and control. The electronics industry is particularly sensitive to these issues because of rapid changes in technology. In the manufacture of printed circuit board assemblies (PCBA), the product goes through three stages of realization: design, resource planning and manufacturing. The estimation of the development cycle time is an important tool for the electronics industry because of the need for tight product introduction planning and the control thereof. Most of the past work in cycle time estimation tools is in the manufacturing phase. Similar analysis of the design phase cycle time is very important because the time taken in design and the decisions made in the phase significantly affect the later phases. The paper introduces a new approach to this problem called activation , which is used to build a cycle time estimation model for the design phase for PCBA. A small-scale case study using data obtained from electronics designers demonstrates the capability of the new method.     

复合材料结构制造成本估算模型及软件开发

基于制造工艺过程的成本估算模型,采用Delphi 可视化编程语言和SQL server数据库开发工具,开发了复合材料制造成本评估软件。介绍了基于制造工艺过程的成本估算模型的基本特点,重点讨论了工艺时间模型并分析了构件复杂程度对工艺时间的影响。此外,通过引入曲率熵的概念,对前人提出的构件复杂性因子进行了改进,以便更合理地描述构件的复杂度。提出了成本估算软件的总体方案,确定了软件实现流程,并建立了成本数据库管理系统。列举了用该软件对一种复合材料单曲率板的制造成本进行估算的过程。应用所开发的软件对某型飞机的复合材料副翼和金属副翼的制造成本进行了估算,估算结果表明,复合材料副翼由于采用了低成本工艺与整体化的设计理念,其制造成本低于金属副翼。      

Cost effective manufacturing process of thermoplastic matrix composites for the traditional industry: the example of a carbon-fiber reinforced thermoplastic flywheel

Composite materials were successfully introduced and are now widely used for aerospace applications. Due to their high specific strength and stiffness, polymer-based composite materials should also be attractive candidates for many products of the traditional industries such as gas turbines, oil industry, or water and gas piping. The introduction of composite materials in the traditional industry is however a very slow process. Many factors can be identified as possible reasons such as the lack of previous examples on which to assess the durability of such composite products or reparability issues. However, the major factor hindering a broader use of composite materials for traditional products remains cost. Unlike the case of the aerospace industry, the use of composite materials is often not an enabling technology for traditional products: steel designs can be modified in order to increase the current product limitations. Therefore, the price of the composite system should be competitive when compared to the price of the equivalent system based on traditional materials such as steel or aluminum. In order to illustrate this concept, the case of steel risers for deepwater oil production is shortly discussed in the introduction of the present paper. When trying to reduce the price of composite products, the challenge often lies in lowering the manufacturing cost. The present paper focuses on applied manufacturing methods for various parts and products aiming to reduce cost. The associated performance of hot pressing and winding of short fiber and continuous fiber reinforced thermoplastic (AS4/PEEK) are compared for a high-speed flywheel type of application. Based on the mechanical performance and ease of fabrication, conclusions are drawn on a promising area of further investigation.     

A review on strategic capacity planning for the semiconductor manufacturing industry

Due to the high capital investment cost in the semiconductor manufacturing industry, strategic capacity planning plays an important role in improving business performance. The reasons that make these problems especially difficult are: the complex fabrication process, rapid changes in technology and products, the long lead time and the high cost of capacity increment, and the high uncertain demand and capacity. Hence, a review of the existing solutions to capacity planning to cope with these difficulties is important for developing new methodologies and practices. In this paper, we provide a review of the current research and fundamental methods in strategic capacity planning, identify emerging methods for capacity planning, and take an in-depth look at future research interests.     

System for early cost estimation of die-cast parts

Early cost estimate of a part is important information and forms a basis for preparing quotations, which are competitive from a market point of view. It is seen that a commonly adopted approach of variant cost estimation based only on geometric information of the component is not always accurate. This is also true in the case of die-cast parts. The geometric complexity of the part, tooling complexity, part and tool material, processing cost, and manufacturing resources for producing the part all need to be considered for accurate cost estimation. This paper deals with a comprehensive system developed to estimate and analyze the manufacturing cost of die-cast parts. A computer-aided cost-estimation system has been developed that applies manufacturing process as well as manufacturing resource considerations in addition to part feature complexity. Use of the proposed system is demonstrated in selecting the optimum number of cavities and the appropriate manufacturing resources under machine-related constraints. Further, the cost-estimation system developed herein is used for carrying out feature sensitivity analysis to identify design features that add significant cost to the part. The use of this system for optimal machine loading in multiple parts situation is also demonstrated.     

Optimizing OEE,productivity and production cost for improving sales volume in an automobile industry through TPM: a case study

The aim of this paper is to investigate how increase in sales volume has evolved by improving overall equipment effectiveness (OEE) of machines, plant productivity and production cost through total productive maintenance (TPM) initiatives in a reputed tractors manufacturing industry in India. In the present scenario of global competitive market, the manufacturing industry needs to improve their operational performance for surviving and prospering. TPM is practised by industry as a business tool for rapid and continuous improvement in its manufacturing capabilities. OEE offers a powerful control tool to overcome production deficiencies and operational performance constrains. Productivity and manufacturing cost are also crucial operational measures to analyse the manufacturing performance. In this study, evaluation and analysis of the methodology adopted for improving sales volume through TPM initiatives was carried out using an interactive research approach. The industrial example on the application of OEE tool demonstrates that it has a remarkable potential to enhance the equipment effectiveness. The empirical findings of the study reveal that augmented OEE and productivity, and reduced production cost resulted to double the sales revenue and triple the profit within a period of three years. The industry also achieved notably tangible and intangible benefits with the TPM implementation.     

Tissue engineering and regenerative medicine: manufacturing challenges

Tissue engineering and regenerative medicine are interdisciplinary fields that apply principles of engineering and life sciences to develop biological substitutes, typically composed of biological and synthetic components, that restore, maintain or improve tissue function. Many tissue engineering technologies are still at a laboratory or pre-commercial scale. The short review paper describes the most significant manufacturing and bio-process challenges inherent in the commercialisation and exploitation of the exciting results emerging from the biological and clinical laboratories exploring tissue engineering and regenerative medicine. A three-generation road map of the industry has been used to structure a view of these challenges and to define where the manufacturing community can contribute to the commercial success of the products from these emerging fields. The first-generation industry is characterised by its demonstrated clinical applications and products in the marketplace, the second is characterised by emerging clinical applications, and the third generation is characterised by aspirational clinical applications. The paper focuses on the cost reduction requirement of the first generation of the industry to allow more market penetration and consequent patient impact. It indicates the technological requirements, for instance the creation of three-dimensional tissue structures, and value chain issues in the second generation of the industry. The third-generation industry challenges lie in fundamental biological and clinical science. The paper sets out a road map of these generations to identify areas for research.     

The impact of environmental issues on the UK printed circuit boardindustry

The need for environmentally responsible manufacturing is forcing industry to change the way it produces its products and offers its services. This is evident in the electronics industry and especially so in the printed circuit board (PCB) manufacturing sector. PCB manufacture requires numerous chemical processes and materials, many of which contain chemicals that can be difficult to dispose of and harmful to the environment. With growing awareness of environmental issues and stricter legislation, the treatment and disposal of these materials can have a significant cost impact on the profitability of UK producers. This article discusses some of the environmental challenges facing the industry and highlights the fact that improvements in environmental performance can actually be used to commercial advantage     

Cost estimation system for machined parts

Estimating the manufacturing cost of a machined part is a critical task with high importance to manufacturing firms. Accurate cost estimation is important for cost control, successful bidding for jobs, and maintaining a competitive position in the marketplace. There are three main approaches towards cost estimation: estimation based on past experience (variant cost estimation), estimation based on explicit cost computations, and parametric cost estimation. This paper presents a hybrid cost estimation system for rotational parts that uses a combination of the variant approach and explicit cost calculations. The variant approach is used to retrieve machining parameters from a database of past parameters. The explicit cost calculations are based on the part geometry, the cutting tools available and the machining parameters retrieved. The system presented calculates the time that a part needs to stay on the machine. This time, which includes processing, set-up (chucking and re-chucking) as well as tool changes, is used to find the machining cost.     

热压釜成型复合材料波纹梁工艺工时估算

成本估算是目前复合材料领域开发研究的关键问题之一,而工艺工时估算又是制造成本估算的核心。本文中建立复合材料制造工艺工时估算模型,以热压釜成型复合材料波纹梁为研究对象进行理论分析和实验研究,给出此估算模型中估算变量和方程参数的确定方法并应用最小二乘法将所得数据进行拟合,其结果与实验结果基本一致。介绍了估算模型中参数随制件曲度变化的修正方法,为实现不同结构设计的工时估算提供指导。     

Green Remanufacturing Engineering and Its Development Strategy in China

Made in China 2025 proposes that “develop the remanufacturing industry vigorously, implement high-end remanufacturing, smart remanufacturing, and in-service remanufacturing, advance the identification of remanufacturing products, and promote sustainable and healthy development of the manufacturing industry”. Remanufacturing is an extension of the manufacturing industry chain, and it is an important part of advanced manufacturing and green manufacturing. The product function, technical performance, greenness and economy of the remanufacturing products are no worse than those of the new products. The cost of remanufacturing products is only about 50% of new products. Remanufacturing can save energy 60%, and material 70%, so the adverse impact on the environment is significantly reduced. At present, China’s remanufacturing industry is developing rapidly, and the manufacturing pilot has been in full swing. Meanwhile, the policies and regulations, basic theory, key technology, and industry standards of remanufacturing have been continuously innovated and completed.     

Optimal Burn-in Time to Minimize Cost for Products Sold Under Warranty

For products with an initially high failure rate, burn-in can be used to reduce the warranty cost. This paper examines the optimal burn-in time to achieve a trade-off between the reduction in the warranty cost and the increase in the manufacturing cost (as burn-in can be viewed as a part of the manufacturing process). Conditions for burn-in to be beneficial are derived for various warranty policies. A numerical example is presented.     

基于特征的制造成本评价系统

简要论述了智能决策支持系统（ＩＤＳＳ）技术，然后介绍了基于特征的制造成本评价系统的系统结构，提出了基于特征制造成本预估算法。最后论述了基于特征的成本预估评价系统工作原理，并给出该算法和系统运行实例。     

先进复合材料可制造性中的成本估算理论框架

飞行器复合材料构件的可制造性评价是其结构制造工艺方案决策的重要依据,成本是评价体系中的一个重要指标。本文概述了先进复合材料可制造性中的成本概念及组成,应用过程估算方法建立了成本指标的估算理论框架及初步模型。通过对工时估算理论的分析,提出了适合于过程估算方法的工时概念关系式。应用本文所提出的先进复合材料可制造性成本估算理论,能够有效地建立较为实用的可制造性成本评价估算模型。     

Tolerancing techniques: the state-of-the-art

The intense global competition to produce quality products at a low cost has led many industrial nations to consider mechanical tolerances as a key factor to bring about cost saving as well as to remain competitive. In the last two decades, some work has been done in the area of tolerance techniques. In this paper a comprehensive summary of the state-of-the-art and the projection of future trends in tolerancing techniques is presented to describe improved techniques available today and to aid in guiding research for the future. This paper reviews the status of theory and practice of how manufacturing and assembly processes are characterized for relating tolerancing to process or production cost. The specification of tolerancing on the dimension of the manufactured part has a significant impact on the final production cost. Tight tolerances can result in excessive process cost, while loose tolerances may lead to increased waste and assembly problems. This paper systematically reviews the state-of-the-art by classifying more than 50 papers written so far into five categories. They are, the dimensional tolerances chain technique, geometrical modelling in tolerances, statistical and probabilistic methods in tolerancing, tolerances based on analysis and synthesis, tolerances based on cost-tolerance algorithms and design methods. Future areas of research and the unresolved issues have been presented that will serve as a springboard for researchers to investigate and produce solutions for the end of this century. The present problems and issues once resolved, will revolutionize the manufacturing industry as the year 2000 approaches!     

Informing additive manufacturing technology adoption: total cost and the impact of capacity utilisation

Informing Additive Manufacturing (AM) technology adoption decisions, this paper investigates the relationship between build volume capacity utilisation and efficient technology operation in an inter-process comparison of the costs of manufacturing a complex component used in the packaging industry. Confronting the reported costs of a conventional machining and welding pathway with an estimator of the costs incurred through an AM route utilising Direct Metal Laser Sintering (DMLS), we weave together four aspects: optimised capacity utilisation, ancillary process steps, the effect of build failure and design adaptation. Recognising that AM users can fill unused machine capacity with other, potentially unrelated, geometries, we posit a characteristic of ‘fungible’ build capacity. This aspect is integrated in the cost estimation framework through computational build volume packing, drawing on a basket of sample geometries. We show that the unit cost in mixed builds at full capacity is lower than in builds limited to a single type of geometry; in our study, this results in a mean unit cost overstatement of 157%. The estimated manufacturing cost savings from AM adoption range from 36 to 46%. Additionally, we indicate that operating cost savings resulting from design adaptation are likely to far outweigh the manufacturing cost advantage.     

Cost analysis of alternative automated technologies for composite parts production

Composite material usage in aircraft has been rising since the 1990s, with significant increases in manufacturing productivity and repeatability due to automation in the production of aeronautic parts made of composite materials, becoming a strong driver for widespread adoption of composites in this industry. Automated Tape Layup (ATL) and Automated Fibre Placement (AFP) are two of the most important automated manufacturing technologies within aeronautics composites, although their cost implications and economic comparison have not been widely studied. This paper presents an economic evaluation of ATL and AFP technologies. Using process-based cost models, the manufacturing process of a horizontal stabiliser is modelled, determining for each technology the associated consumption and use of resources and their implications towards the part final cost. Results show that ATL is less expensive than AFP, due to lower material costs, although with less material efficiency and slower cycle time.     

Parametric cost analysis for web-based e-commerce of layer manufactured objects

Web-based e-commerce of rapid prototyping services is going to be a widely diffused methodology used to compete in a global market. A competitive market imposes a very accurate estimation of prototyping price. Prototype costs depend on many factors, some of which may be easily deduced, while some others consist in a complex function of the geometric model properties and of the specific technology employed to build a physical model. Build time, which affects some components of the prototype's build cost, is a critical factor to deduce. Build time depends not only on the prototype dimensions but also on the complexity of the shape that, in turn, affects the movement of the tool to form the object. A parametric approach to build cost estimation, suited for web-based e-commerce, is presented in this paper. Significant cost driving factors of layer manufactured objects are identified and instruments to evaluate them are proposed. Special attention has been paid to define a parametric approach to build time estimation. The proposed parametric approach analyses the geometrical features, which typically affect the build time of the main layer manufacturing technologies. The method is verified in some test cases related to FDM technology.     

复合材料制造成本估算尺寸效应研究

探讨了复合材料制造成本估算的尺寸效应理论,将理论扩展应用于一阶动力学系统、线性控制系统和质点运动模型中。研究结果表明,在复合材料制造成本估算过程中尺寸效应的影响并不是线性的,通过分析不同制件尺寸及不同成型工艺的制造成本,充分验证了尺寸效应理论的可行性。