DOCSLIB.ORG

Computers in Foundries

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Computers in Foundries Computers in Foundries Dr Thoguluva Raghavan Vijayaram* and Dr Paolo Piccardo** * Principal Lecturer, Faculty of Engineering and Technology, FET MMU, Multimedia University, Melaka Campus Melaka, Malaysia ** Professor, Dipartimento di Chimicae Chimica Industriale, DCCI, Sezione di Chimica Inorganicae Metallurgia, Genoa University, Genoa, Italy ABSTRACT RIASSUNTO Computers have now entered into the foundry I computer sono entrati prepotentemente nella fonderia, engineering. Foundry mechanization and modernization un’arte antica che si è evoluta in una scienza moderna. La are of considerable importance today when the foundry fonderia è oggi completamente monitorata e controllata has evolved from an ancient art into a modern science dal computer, che assume un’importanza primaria per and it is fully controlled and monitored by computers. migliorare la qualità dei getti e la produttività. Dal punto Modernization is the only key to improve casting quality di vista industriale, i PC sono da tempo utilizzati nelle and productivity. From industrial point of view, they aree amministrative della finanza, contabilità, gestione have been in use in the administrative areas of finance, del personale, salari, stipendi, gestione del magazzino. accounting, personnel records, wage, salaries, and Attualmente molti sistemi di macchine per fonderia sono inventory control for a long period. Many foundry machine computerizzati. Grazie al computer la fatica e lo stress systems are computerized. Due to the entry of computers per i lavoratori e lo staff si sono ridotti notevolmente. La in foundries, fatigue and strain on the workers and staffs cultura del lavoro è notevolmente migliorata, e con essa si have been considerably reduced during working and sono sviluppati il coinvolgimento, la creatività e il senso di work culture has improved tremendously. Improved work partecipazione. Questo articolo di rassegna presenta ruolo, culture can lead to a sense of participation, involvement, prospettive e applicazioni del computer nella fonderia; in and creativity. This review paper discusses on the role, particolare si sofferma sulla progettazione degli stampi, prospects, and application of computers in foundries. sulla simulazione numerica del complesso processo di Besides, an introduction on the computer aided foundry solidificazione e sulle linee di produzione computerizzate e model design and computer aided foundry die design are automatizzate. Vengono infine prospettate le applicazioni presented precisely in this paper. It also discusses on the dei sistemi esperti e son passati in rassegna vari tipi di numerical simulation of casting solidification performed in pacchetti software comunemente adottati nella fonderia. foundries and a brief information about the computerized and automated foundry line have been provided in this technical paper. The applications of expert systems in foundries and various types of foundry software packages commonly used in the metal casting industries are explained in detail in this review paper. KEYWORDS Computer aided foundry model, Computer aided foundry die-design, casting design and numerical simulation, foundry expert systems, foundry software packages. 28 Metallurgical Science and Technology Vol. 30-2 - Ed. 2012 INTRODUCTION emission in foundries are monitored and controlled by computers. Computers with the aid of imaging Foundry technology deals with the processes of systems perform micro structural characterization producing castings in molds made in either sand and capture photomicrographs since software is or some other material. Metal casting is the oldest available in them [2, 4]. manufacturing processes. Today, a variety of molding processes and melting equipment are available to cast different types of metals and alloys in foundries. However, the methods and techniques of III. COMPUTER AIDED FOUNDRY production of castings have changed considerably, MODELS DESIGN the fundamental principles remain almost the same. The traditional approach to resolve the design and Castings have several characteristics that clearly the process planning tasks, commonly used in a define their role in modern equipment used for foundry, is that the plans are handed over to the transportation, communication, power, agriculture, experts who specify the procedures to make the construction and in industry. Cast metals are required cast product and draw it. The designers, using their in various shapes and sizes and in large quantities for experience and knowledge, generate projects and making machines and tools, which in turn work to instructions for manufacturing the foundry products provide all necessities and comforts of life. However, based on the design specifications and the available certain advantages inherent in castings such as design installations and operators [1]. Consistent designing and metallurgical advantages and in the casting and planning require knowledge of casting process itself, endow them with superiority over other processes and experience. This has led to the manufacturing methods. Foundry mechanization and development of Computer Aided Process Planning modernization are of considerable importance today (CAPP) systems, which are becoming more and when the foundry has evolved from an ancient art more important in this field. CAPP systems are into a modern science. Computers have entered beginning to be developed as a link between design into all industrial applications, and more so in foundry and manufacturing, filling the existing gap between technology [1, 4]. CAD (Computer Aided Design) and CAM (Computer Aided Manufacturing). CAPP allows the user to develop an integrated structure that deals with the II. PROSPECTS flow of information between CAD, CAPP, MRP and numeric control (NC) activities within the company Nowadays, casting quality is considered as [2,3]. There are two approaches to computer-aided an important one. This satisfies the customer process planning. The first is the variant approach, in requirements in many ways. To achieve and maintain which a new process plan is generated using existing quality, it is necessary to control the production standard process plans stored in the database. The process firstly. Manual control does not fulfill to attain second is the generative approach, in which a new the expected quality of castings. So, computers process plan is generated from scratch, i.e. it will are introduced to manage and control the process not use any standard existing process plan. The efficiently. Application of computers plays a vital role basic requirement for a generative process planning to control the entire casting process, quality, metal system is to interpret the given component model composition, liquid metal handling, and to perform drawing in terms of manufacturable features. The casting defect analysis with the aid of expert main objective is the realization of a computer-aided systems. Besides, computers help to simulate the system to help, automatically select and finally define casting solidification during processing. This paves the parameters of a foundry models. In the applied the way to design the casting correctly and hence methodology, the steps are divided into three parts: to avoid major defects like hot spots and also to knowledge acquisition, the activity modification and identify and locate the stress concentration zones. finally development and implementation of the tool It provides the temperature history of castings, [2-4]. detailed information on the temperature contours, Foundries represent an important sector of the and distribution inside the solidifying casting can be casting manufacturing industry. One of the most understood. At present, different types of software important aspects is the designing of the models packages are available to perform analysis on with their equipment. The successful casting of a various aspects. pre-designed shape is heavily dependent on the skill Among them, finite element analysis is an important and experience of the foundry engineer and this is tool to study the temperature, the stress distribution a time consuming step in a production environment. and micro structural evolution. Modern foundries are Thus, the main objective is the realization of a automated and absolutely controlled by computers computer-aided system to define the models with minimal manual assistance. Pollution and parameters as machining allowance, draft corner, Vol. 30-2 - Ed. 2012 Metallurgical Science and Technology 29 radius, dimension, feed head, flask and pouring simulating the solidification of the molten metal in system. The software tool used for the prototype the ceramic mold. system is an object-oriented programming In recent years, Computer Aided Design has language called Visual Basic, used to create the become an essential tool for designing metal parts. main functional modules. The computer system CAD eliminates the manual drafting process, and starts with the geometrical definition of the part. allows the engineer to design more sophisticated Based on the geometrical dimensions, the program parts with greater precision. However, the ultimate executes the calculations of the model parameters output of expensive software and computing power in order to obtain a correct design. The result gives is a two-dimensional paper drawing. the parameters for model and a proposal for the dimensions, which can be modified. The main Foundries must interpret the part's design feature of the proposed integrated approach is drawing into a pattern design,
Load more

Recommended publications
  • Compression Behavior of Entrapped Gas in High Pressure Diecasting
    Materials Transactions, Vol. 53, No. 3 (2012) pp. 483 to 488 ©2012 Japan Foundry Engineering Society Compression Behavior of Entrapped Gas in High Pressure Diecasting Yasushi Iwata, Shuxin Dong, Yoshio Sugiyama and Hiroaki Iwahori Toyota Central R&D Labs., Inc., Nagakute 480-1192, Japan Die castings generally contain a large quantity of porosities due to the entrapment of air or gas in molten metal during mold filling. Although the entrapped air or gas is compressed by high casting pressure during pressurization, it will eventually remain in the castings as defects after solidification. Therefore, it is important to clarify the relation between the volume of gas defects and the pressure applied to the molten metal so as to optimize the casting design. In this study, we investigated the compression behavior of entrapped gas during casting. We determined the volume of gas defects and gas content in die castings by density measurement and vacuum fusion extraction method respectively. Then we calculated the gas pressure in the defects from the above volume of defects and gas content, and compared with the die casting pressure. The calculated gas pressure in the defects was found to be not equal to the die casting pressure, but equal to the pressure of the molten metal just before it dropped abruptly due to the complete blocking of the liquid metal channel by solidification. From the experimental results, the behavior of the entrapped gas can be inferred as follows. Immediately after the mold was filled with molten metal, the entrapped gas was instantly compressed. After that, the pressure of molten metal decreased gradually with the progress of solidification of the molten metal channel, and the volume of entrapped gas increased correspondingly until the pressure of the molten metal dropped abruptly.
    [Show full text]
  • Defect Analysis for Sand Casting Process (Case Study in Foundry of Kombolcha Textile Share Company)
    International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 07 Issue: 01 | Jan 2020 www.irjet.net p-ISSN: 2395-0072 Defect Analysis for Sand Casting process (Case Study in foundry of Kombolcha Textile Share Company) Wossenu Ali Wollo University, Kombolcha Institute of Technology, Mechanical Engineering Department, Kombolcha, Ethiopia ---------------------------------------------------------------------***---------------------------------------------------------------------- Abstract - This research aimed to identify the cause of casting product. Deviation of any process parameter casting defect and to suggest possible remedies in order will cause one or more casting defects on the product. to produce conforming casting product in the foundry of Kombolcha textile share company, Ethiopia. During A few manufacturing industries are found in Ethiopia casting defect analysis, the common casting defects in which casting process is the one that uses to produce blowholes, pinholes and shrinkage were identified. The metallic parts. These parts use for internal customers major and minor process variables which were who wants to substitute their broken spare parts. Since responsible for each casting defects were indicated using the process is supported by shop-floor trial and there is fishbone diagram. For analysis of possible causes, shortage of skilled workers, the casting products Experiments were conducted for moulding sand to produced are not quality product to satisfy customers determine clay content and grain fineness number need. Solving this problem in these foundries is (GFN). For defective part, composition analysis using important to satisfy customers need. spectrometer was also done. Analysis showed that high Casting process in foundry of Kombolcha textile clay content (52.7%) of moulding sand, wrong gating Share Company produces parts such as Armature disk, system design, incorrect pattern design and unknown front flange, real flange, and pulley of different size, pouring temperature were responsible for the defects.
    [Show full text]
  • Minimization of Casting Defects in Aluminum Alloy Wheels of Grade A356.2 K.Pundari Kaksha #1 P.Satish Reddy #2 N.Guru Murthy #3 S.Siva Kumar #4 PG Scholar, Assoc
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by International Journal of Science Engineering and Advance Technology (IJSEAT) ISSN 2321-6905 February- 2018 International Journal of Science Engineering and Advance Technology, IJSEAT, Vol. 6, Issue 2 Minimization of Casting Defects In Aluminum Alloy Wheels of Grade A356.2 K.Pundari Kaksha #1 P.Satish Reddy #2 N.Guru Murthy #3 S.Siva Kumar #4 PG Scholar, Assoc. Professor, Asst Professor, Asst Professor Dept of Mechanical Engineering, Prasiddha College of Engg & Tech, Anathavaram [email protected],[email protected],[email protected], [email protected] So, precautions should be taken while casting the wheel. Throughout the production of aluminum ABSTRACT: alloy wheels the typically used raw material is Al- The primary motive of this project is Si casting alloys. As of their good casting identification of the casting defects in Aluminium properties and due to these alloys will provide good alloy wheels, to reduce the losses due to scrap and corrosion resistance and strength so that vehicle rework and also applications of techniques to can acclimatize to road and weather condition. reduce the defects to a minimum level. To identify 1.1 A356.2-COMPOSITION: the defects in the product, the process adopted in casting, inspection and testing procedures are Al - 92.4% studied. Reasons for defects in hub, spoke and rim Si - 6.5%-7.5% are identified. Number of defects occurred in hub, spoke and rim are collected and techniques to Mg - 0.25-0.45% minimize these are suggested.
    [Show full text]
  • Foundry Industry SOQ
    STATEMENT OF QUALIFICATIONS Foundry Industry SOQ TRCcompanies.com Foundry Industry SOQ About TRC The world is advancing. We’re advancing how it gets planned and engineered. TRC is a global consulting firm providing environmentally advanced and technology‐powered solutions for industry and government. From solid waste, pipelines to power plants, roadways to reservoirs, schoolyards to security solutions, clients look to TRC for breakthrough thinking backed by the innovative follow‐ through of a 50‐year industry leader. The demands and challenges in industry and government are growing every day. TRC is your partner in providing breakthrough solutions that navigate the evolving market and regulatory environment, while providing dependable, safe service to our customers. We provide end‐to‐end solutions for environmental management. Throughout the decades, the company has been a leader in setting industry standards and establishing innovative program models. TRC was the first company to conduct a major indoor air study related to outdoor air quality standards. We also developed innovative measurements standards for fugitive emissions and ventilation standards for schools and hospitals in the 1960s; managed the monitoring program and sampled for pollutants at EPA’s Love Canal Project in the 1970s; developed the basis for many EPA air and hazardous waste regulations in the 1980s; pioneered guaranteed fixed‐price remediation in the 1990s; and earned an ENERGY STAR Partner of the Year Award for outstanding energy efficiency program services provided to the New York State Energy Research and Development Authority in the 2000s. We are proud to have developed scientific and engineering methodologies that are used in the environmental business today—helping to balance environmental challenges with economic growth.
    [Show full text]
  • A Work Study on Minimize the Defect in Aluminium Casting
    International Journal of Emerging Technologies in Engineering Research (IJETER) Volume 3, Issue 1, October (2015) www.ijeter.everscience.org A Work Study on Minimize the Defect in Aluminium Casting Er. Satish Kumar Assistant Professor, M.E Department, Dungarpur College of Engineering and Technology, Dungarpur (Raj), India. Er. Amit Tiwari Research Scholar, (Production Engineering), Pacific University, Udaipur, Rajasthan, India. Abstract – In the present world with the increasing use of pressure of dry air (0.5 ~ 1.0 kg/mm2) on the surface of molten Aluminium alloy wheels in automotive industry the Aluminium metal in the bath. The pressure causes the metal to rise through foundry industry had to focus on the quality of the products. The a central Ceramic riser tube into the die cavity. The dies are quality of a foundry industry can be increased by minimizing the provided ample venting to allow escape of air, the pressure is casting defects during production. Aim of the current study is to maintained till the metal is solidified ; then it is released study the production line of an aluminium alloy wheel manufacturing industry and to improve the quality of production enabling the excess liquid metal to drain down the connecting using quality control tools. This study shows the systematic tube back in to the bath. Since this system of upward filling approach to find the root cause of major defects in aluminium requires no runners and risers, there is rarely any wastage of castings using defect diagnostic approach as well as cause and metal. As positive pressure maintained to force the metal to fill effect diagram.
    [Show full text]
  • MSL Engineering Limited Platinum Blue House 1St Floor, 18 the Avenue Egham, Surrey, TW20 9AB
    SMR Final Report 121404 Purpose of Issue Rev Date of Issue Author Agreed Approved Issued for information 0 Aug 2004 SM Issued for internal comment 1 November 2004 AFD DJM JB Issued as Final Report 2 December 2004 AFD DJM JB This Final report has been reviewed and approved by the Mineral Management Service. Approval does not signify that the contents necessarily reflect the views and policies of the Service, nor does mention of trade names or commercial products constitute endorsement or recommendation for use. This study was funded by the Mineral Management Service, U.S. Department of the Interior, Washington, D.C., under Contract Number 1435-01-04-CT-35320 ASSESSMENT OF REPAIR TECHNIQUES FOR AGEING OR DAMAGED STRUCTURES Project #502 DOC REF C357R001 Rev 1 NOV 2004 MSL Engineering Limited Platinum Blue House 1st Floor, 18 The Avenue Egham, Surrey, TW20 9AB Tel: +44 (0)1784 439194 Fax: +44 (0)1784 439198 E-mail: [email protected] C357R001Rev 2, December 2004 MMS Project #502 NUMBER DETAILS OF REVISION 0 Issued for information, August 2004 1 Issued for comment, November 2004. Extensive revisions throughout, including restructuring of report. 2 Issued as Final Report, December 2004. Conversion table added, Figure showing clamp details to avoid added, and general editorial revisions. C357R001Rev 2, December 2004 MMS Project #502 Assessment of Repair Techniques for Ageing or Damaged Structures By Dr. Adrian F Dier MSL Services Corporation Final Project Report: ASSESSMENT OF REPAIR TECHNIQUES FOR AGEING OR DAMAGED STRUCTURES MMS Project Number 502 November 2004 C357R001Rev 2, December 2004 i This Final report has been reviewed a nd approved by the Mineral Management Service.
    [Show full text]
  • The PEWTER COLLECTORS' CLUB of AMERICA INC
    The PEWTER COLLECTORS' CLUB ofAMERICA INC. THE BUllETIN Summer 2004 Volume 13 Number 1 PCCA Officers President ................................................ Richard C. Graver First Vice President ................................... David M. Kilroy Second Vice President ................... Robert G. Eisenbraun Treasurer ....................................................... Terry 1. Ashley Secretary ........................................................ Robert Horan Bulletin Editor Garland Pass 71 Hurdle Fence Drive Avon, CT 06001-4103 Email: [email protected] Editorial Board Garland Pass, Chair William R. Snow Richard Bowen Charles V. Swain Wayne A. Hilt Melvyn D. Wolf For the names and addresses of all club officers and committee heads, please refer to the latest issue of the PCCA Membership Directory TABLE OF CONTENTS Page 2 .......................................... President's Letter, Richard C Graver Page 3 .......................................... Folk Art Engraving on Pewter, Garland Pass Page 34 ......................................... Pewter Imports 1750, Charles V. Swain Page 35 .......................................... Boardman Measure of 1818, Andrew F Turano Page 36 ......................................... A New Gleason Candlestick, Melvyn D. Wolf, M.D. Page 37 .......................................... Copper Bottom Teapots, Melvyn D. Wolf, M.D. Page 38 .......................................... New York Handle Porringers Addendum, Melvyn D. Wolf, M.D. Page 39 .......................................... The Other Relief
    [Show full text]
  • Manufacturing Technology I Unit I Metal Casting
    MANUFACTURING TECHNOLOGY I UNIT I METAL CASTING PROCESSES Sand casting – Sand moulds - Type of patterns – Pattern materials – Pattern allowances – Types of Moulding sand – Properties – Core making – Methods of Sand testing – Moulding machines – Types of moulding machines - Melting furnaces – Working principle of Special casting processes – Shell – investment casting – Ceramic mould – Lost Wax process – Pressure die casting – Centrifugal casting – CO2 process – Sand Casting defects. UNIT II JOINING PROCESSES Fusion welding processes – Types of Gas welding – Equipments used – Flame characteristics – Filler and Flux materials - Arc welding equipments - Electrodes – Coating and specifications – Principles of Resistance welding – Spot/butt – Seam – Projection welding – Percusion welding – GS metal arc welding – Flux cored – Submerged arc welding – Electro slag welding – TIG welding – Principle and application of special welding processes – Plasma arc welding – Thermit welding – Electron beam welding – Friction welding – Diffusion welding – Weld defects – Brazing – Soldering process – Methods and process capabilities – Filler materials and fluxes – Types of Adhesive bonding. UNIT III BULK DEFORMATION PROCESSES Hot working and cold working of metals – Forging processes – Open impression and closed die forging – Characteristics of the process – Types of Forging Machines – Typical forging operations – Rolling of metals – Types of Rolling mills – Flat strip rolling – Shape rolling operations – Defects in rolled parts – Principle of rod and wire drawing – Tube drawing – Principles of Extrusion – Types of Extrusion – Hot and Cold extrusion – Equipments used. UNIT IV SHEET METAL PROCESSES Sheet metal characteristics – Typical shearing operations – Bending – Drawing operations – Stretch forming operations –– Formability of sheet metal – Test methods – Working principle and application of special forming processes – Hydro forming – Rubber pad forming – Metal spinning – Introduction to Explosive forming – Magnetic pulse forming – Peen forming – Super plastic forming.
    [Show full text]
  • Introduction to Casting for 3D Printed Jewelry Patterns the Way Jewelers Work Is Changing, and Castable Photopolymer Resins Are Leading the Way
    Introduction to Casting for 3D Printed Jewelry Patterns The way jewelers work is changing, and castable photopolymer resins are leading the way. From independent designers concepting and prototyping in their studios, to casting houses increasing capacity and diversifying their offerings, digital fabrication techniques are increasingly key to growing a successful jewelry business. In this guide, learn how to cast fine jewelry pieces from patterns 3D printed on the Form 2. Request a Sample Part 3D Printed in Castable Wax Resin › Learn About Casting and Jewelry Production from Formlabs › July 2019 | formlabs.com What Is Direct Investment Casting? Direct investment casting, or lost wax casting, is a popular moldmaking technique that can be used to fabricate small and large parts in a wide variety of metals. Originating over 5,000 years ago, casting enables creators to work with a wide variety of materials and is one of the easiest ways to make metal parts. In investment casting, a hollow mold is created from a hand-sculpted or 3D printed master pattern. The master is immersed in a refractory casting material (or “investment”), which dries and hardens. The wax or 3D printed pattern is burned out, leaving a negative mold of the design. Metal is poured into this hollow cavity to create the final part. Wax patterns for intricate jewelry are complicated to produce by hand, and in a world driven by high demand and fast fashion, it can be difficult for hand-crafted pieces to keep pace. Advanced materials and affordable in-house 3D printers like the Form 2 are changing the way jewelry manufacturers and designers work, bringing industrial quality to the desktop and making it easier to produce and fit complicated geometries that once required hours of meticulous labor.
    [Show full text]
  • SIMPLE SOLUTIONS THAT WORK! Committed to Sharing Best Practices for the Metalcasting and Die Casting Industry
    ENGLISH / ESPAÑOL ISSUE 13 • FALL 2020 SIMPLE SOLUTIONS THAT WORK! Committed to sharing best practices for the metalcasting and die casting industry THE FOCUS OF THIS ISSUE: Defect Prevention WELCOME TO OUR “DEFECT PREVENTION” ISSUE With so many ways to make a bad casting, it’s no wonder that metal casters have taken a leadership position in the manufacturing world by building quality—in from the start. Unlike other manufacturing processes that rely heavily on final inspection as a primary means of ensuring quality, foundries understand better than others that you can’t wait until the casting is machined to test it. Over the past ten years, the foundry production floor has literally been upended with important changes, all designed to produce higher quality parts, at less cost—with reduced scrap. Six Sigma principles, robotic workcells, Additive Manufacturing, and Smart Technologies are all being deployed to deliver higher quality castings with repeatable processes. Today, everyone on the foundry floor is involved in the prevention of defects and this work is never, ever done. This issue is devoted to this subject because it’s something that you can’t talk about enough. We hope you find the defect prevention ideas in this issue (that range from binders and the mixing process, melting, analysis, materials, and molding) techniques you can use today. I would like to thank all of our contributors in this issue for their insightful articles. Special thanks to Innovative Casting Technologies, Dualtech Foundry’s Laboratory Manager Scott Gill for appearing on the cover of this issue. As always, thank you for reading our 13th issue of Simple Solutions That Work! GET THE FREE APP! Jack Palmer President, Palmer Manufacturing & Supply, Inc.
    [Show full text]
  • Technology Reference Guide for Radioactively Contaminated Media
    United States Office of Radiation and Indoor Air EPA 402-R-07-004 Environmental Radiation Protection Program October 2007 Protection Agency (6608J) Technology Reference Guide for Radioactively Contaminated Media TECHNOLOGY REFERENCE GUIDE FOR RADIOACTIVELY CONTAMINATED MEDIA EPA - 402-R-07-004 U.S. Environmental Protection Agency Office of Air and Radiation Office of Radiation and Indoor Air Radiation Protection Division Center for Radiation Site Cleanup Prepared Under: Contract No. 4W-2323-YTSX DISCLAIMER This Technology Guide, developed by USEPA, is meant to be a summary of information available for technologies demonstrated to be effective for treatment of radioactively contaminated media. Inclusion of technologies in this Guide should not be viewed as an endorsement of either the technology or the vendor by USEPA. Similarly, exclusion of any technology should not be viewed as not being endorsed by USEPA; it merely means that the information related to that technology was not so readily available during the development of this Guide. Also, the technology-specific performance and cost data presented in this document are somewhat subjective as they are from a limited number of demonstration projects and based on professional judgment. In addition, all images used in this document are from public domain or have been used with permission. i ACKNOWEDGEMENTS This Guide was developed by the Radiation Protection Division (RPD) of EPA’s Office of Radiation and Indoor Air (ORIA). Mr. Edward Feltcorn of ORIA’s Center for Radiation Site Cleanup,
    [Show full text]
  • Shell Mold Casting
    Shell Mold Casting Shell mold casting or shell molding is a metal casting process in manufacturing industry in which the mold is a thin hardened shell of sand and thermosetting resin binder backed up by some other material. Shell mold casting is particularly suitable for steel castings under 10 kg; however almost any metal that can be cast in sand can be cast with shell molding process. Also much larger parts have been manufactured with shell molding. Typical parts manufactured in industry using the shell mold casting process include cylinder heads, gears, bushings, connecting rods, camshafts and valve bodies. The Process The first step in the shell mold casting process is to manufacture the shell mold. The sand we use for the shell molding process is of a much smaller grain size than the typical greensand mold. This fine grained sand is mixed with a thermosetting resin binder. A special metal pattern is coated with a parting agent; (typically silicone), which will latter facilitate in the removal of the shell. The metal pattern is then heated to a temperature of (175 °C-370 °C) . The sand mixture is then poured or blown over the hot casting pattern. Due to the reaction of the thermosetting resin with the hot metal pattern a thin shell forms on the surface of the pattern. The desired thickness of the shell is dependent upon the strength requirements of the mold for the particular metal casting application. A typical industrial manufacturing mold for a shell molding casting process could be 7.5mm thick. The thickness of the mold can be controlled by the length of time the sand mixture is in contact with the metal casting pattern.
    [Show full text]