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1 – 10 of over 1000A.J. Griffiths, P.S. Cheema and D.R. Towill
The UK cast iron foundry industry is surveyed in terms of past performance, present situation and future trends. The traditional “feast or famine” image is discussed in terms of…
Abstract
The UK cast iron foundry industry is surveyed in terms of past performance, present situation and future trends. The traditional “feast or famine” image is discussed in terms of the actions required to improve quality, customer relationships and performance. The article highlights these relationships through its markets, business performance, process route and techological developments that support a new, streamlined, cost‐effective and efficient foundry industry of the 1990s.
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The UK foundry industry employs more people in management and supervision than any other skilled occupation. Almost one in three of these managers will have reached retirement age…
Abstract
The UK foundry industry employs more people in management and supervision than any other skilled occupation. Almost one in three of these managers will have reached retirement age within the next ten years. If the industry hopes to recruit its future management from amongst its technologists and technicians there are not enough young people entering these occupations to provide an adequate supply of managers to replace those retiring. Very few managers and supervisors receive any training prior to their appointment into management. The development of new technology, the introduction of more and more legislation, the need to survive in a depressed and increasingly competitive market, the demand from customers for higher quality castings, the need to continue investment and modernisation at a time of high interest rates are just some of the factors which make the job of managing increasingly complex and time consuming.
P. Zak, J. Lelito, J. Suchy, W. Krajewski, K. Haberl and P. Schumacher
The aim of this paper was to determine fitting parameters in grain density of the magnesium primary phase function in AZ91/SiC composite heterogeneous nucleation model. Nucleation…
Abstract
The aim of this paper was to determine fitting parameters in grain density of the magnesium primary phase function in AZ91/SiC composite heterogeneous nucleation model. Nucleation models have parameters, which exact values are usually not known and sometimes even their physical meaning is under discussion. Those parameters can be obtained after statistical analyze of the experimental data. Specimens of fourteen different composites were prepared. The matrix of the composite was AZ91 and the reinforcement was SiC particles. The specimens differs in SiC particles size (10 μm, 40 μm, 76 μm) and content (0 wt.%, 0.1 wt.%, 0.5 wt.%, 2 wt.%, 3.5 wt.%). They were taken from the region near to the thermocouple, to analyze the undercooling for different composites and its influence on the grain size. The specimens were polished and etched. The mean grain size for each specimen was measured. Specific undercooling for each composite was found from characteristic points on cooling rate curve. Microstructure and thermal analyze gave set of values that connect SiC particles content, their size and alloy undercooling with grain size. Those values were used to approximate nucleation model adjustment parameters. Obtained model can be very useful in modelling composites microstructure.
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This paper gives a review of the finite element techniques (FE)applied in the area of material processing. The latest trends in metalforming, non‐metal forming and powder…
Abstract
This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming and powder metallurgy are briefly discussed. The range of applications of finite elements on the subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for the last five years, and more than 1100 references are listed.
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A Summary by Dr. Alexander Klemin of the Papers Presented Before the Fourteenth Meeting of the Institute held at Columbia University, New York, on January 29–31, 1946…
Abstract
A Summary by Dr. Alexander Klemin of the Papers Presented Before the Fourteenth Meeting of the Institute held at Columbia University, New York, on January 29–31, 1946. AERODYNAMICS IN spite of increased wing loadings, the use of full span wing flaps has been delayed, because of inability to find a suitable aileron. The Development of a Lateral‐Control System for use with Large‐Span Flaps by I. L. Ashkenas (Northrop Aircraft), outlines the various steps in the aerodynamic development of a retractable aileron system well adapted to the full span flap and successfully employed on the Northrop P‐61. Included is a discussion of the basic data used, the design calculations made, and the effect of structural and mechanical considerations. Changes made as a result of preliminary flight tests are discussed and the final flight‐test results are presented. It is concluded that the use of this retractable aileron system has, in addition to the basic advantage of increased flap span, the following desirable control characteristics: (a) favourable yawing moments, (b) low wing‐torsional loads, (c) small pilot forces, even at high speed.
Daniel Günther, Bastian Heymel, Johannes Franz Günther and Ingo Ederer
– This paper aims to present the results that can be achieved using continuous three-dimensional (3D) printing technology.
Abstract
Purpose
This paper aims to present the results that can be achieved using continuous three-dimensional (3D) printing technology.
Design/methodology/approach
In the first section, conventional additive manufacturing and continuous 3D-printing are described and compared against each other. Essential is the new approach to coat the particulate material and to print it on a tilted surface. For this special setup, theoretical considerations for sources of distortions are given. These considerations define the design of the test parts. For the evaluation of a tilted setup a prototype using large dimensions is shown. Of special interest is the exact transportation using a large mass of particulate material.
Findings
The 3D-printing principle is suitable for tilted surfaces, making production without any downtime possible. The parts produced using the prototype continuous 3D-printer have sufficient accuracy for foundry use, although various considerations and the setup show that angular deflections can be caused by inaccuracies in the feeding system.
Research limitations/implications
The parts’ accuracy is additionally affected by the thickness of unbound particle material under the building area. The amount of unbound particle material is of a constructive nature. Thus, the setup is limiting the investigations. Using the current material system, the printing should take place as near to the conveyor belt as possible.
Practical implications
This paper outlines which kind of parts can be manufactured using continuous 3D-printing.
Originality/value
This article shows a first evaluation of parts printed using continuous 3D-printing. It gives a perspective on future designs from rapid prototyping machines based on these principles and shows the possible benefits. The change over from rapid prototyping to rapid manufacturing will be strongly accelerated by said machine design.
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Knight's Industrial Law Reports goes into a new style and format as Managerial Law This issue of KILR is restyled Managerial Law and it now appears on a continuous updating basis…
Abstract
Knight's Industrial Law Reports goes into a new style and format as Managerial Law This issue of KILR is restyled Managerial Law and it now appears on a continuous updating basis rather than as a monthly routine affair.
Sushil Kumar, P.S. Satsangi and D.R. Prajapati
The purpose of this paper is to explore Six Sigma practices in a casting industry, that could improve the green sand casting process in a foundry by reducing the casting defects…
Abstract
Purpose
The purpose of this paper is to explore Six Sigma practices in a casting industry, that could improve the green sand casting process in a foundry by reducing the casting defects. The goal was to determine which variables influenced this evolution and the relative weight of critical success factors as the methodology developed.
Design/methodology/approach
The DMAIC (Define, Measurement, Analyze, Improve, and Control)‐based Six Sigma approach is implemented to improve the green sand casting process and has made the process more robust to quality variations. Analysis of various critical process parameters of the melt shop is also carried out with the help of Taguchi's method of experimental design.
Findings
The proposed techniques optimized control factors, resulting in superior quality and stability of the green sand castings process, which contributes to minimizing the casting defects and improving the Sigma level of the industry.
Research limitations/implications
This study was carried out with some boundaries such as the number of castings of differential housings, available resources, time constraints, etc.
Practical implications
This paper is most valuable for the foundry industry, which can avail the direct benefit of Six Sigma results from the reduction in the number of defects due to improved casting processes and dispels the myths concerning the hardly ever use of Six Sigma in the casting industry.
Originality/value
The novelty of the paper lies in conducting a comparative study on the performance of a Six Sigma project. The paper will be valuable for quality professionals and management personnel in the casting industry.
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Munish Chhabra and Rupinder Singh
This paper seeks to review the industrial applications of state‐of‐the‐art additive manufacturing (AM) techniques in metal casting technology. An extensive survey of concepts…
Abstract
Purpose
This paper seeks to review the industrial applications of state‐of‐the‐art additive manufacturing (AM) techniques in metal casting technology. An extensive survey of concepts, techniques, approaches and suitability of various commercialised rapid casting (RC) solutions with traditional casting methods is presented.
Design/methodology/approach
The tooling required for producing metal casting such as fabrication of patterns, cores and moulds with RC directly by using different approaches are presented and evaluated. Relevant case studies and examples explaining the suitability and problems of using RC solutions by various manufacturers and researchers are also presented.
Findings
Latest research to optimize the current RC solutions, and new inventions in processing techniques and materials in RC performed by researchers worldwide are also discussed. The discussion regarding the benefits of RC solutions to foundrymen, and challenges to produce accurate and cost‐effective RC amongst AM manufacturers concludes this paper.
Research limitations/implications
The research related to this survey is limited to the applicability of RC solutions to sand casting and investment casting processes. There is practically no implication in industrial application of RC technology.
Originality/value
This review presents the information regarding potential AM application – RC, which facilitates the fabrication of patterns, cores and moulds directly using the computer‐aided design data. The information available in this paper serves the purpose of researchers and academicians to explore the new options in the field of RC and especially users, manufacturers and service industries to produce casting in relatively much shorter time and at low cost and even to cast complex design components which otherwise was impossible by using traditional casting processes and CNC technology.
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