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BRITISH STANDARD | | | | | | | | | | | | | | Founding Ð Equipment for the production of lost patterns for the lost foam casting process | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The European Standard EN 892 : 000 has the status of a | | British Standard | | | | | | | | IC S 77 80 | | | | | | | | NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW | | | | | BS EN 12892:2000 Incorporating Corrigendum No BS EN 12892:2000 National foreword This British Standard is the official English language version of EN 12892:2000 The UK participation in its preparation was entrusted to Technical Committee ISE/NFE/9, Foundry technology, which has the responsibility to: Ð aid enquirers to understand the text; Ð present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; Ð monitor related international and European developments and promulgate them in the UK A list of organizations represented on this committee can be obtained on request to its secretary Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled ªInternational Standards Correspondence Indexº, or by using the ªFindº facility of the BSI Standards Electronic Catalogue A British Standard does not purport to include all the necessary provisions of a contract Users of British Standards are responsible for their correct application Compliance with a British Standard does not of itself confer immunity from legal obligations Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages to 16, an inside back cover and a back cover The BSI copyright notice displayed in this document indicates when the document was last issued This British Standard, having been prepared under the direction of the Engineering Sector Committee, was published under the authority of the Standards Committee and comes into effect on 15 June 2000  BSI 19 October 2001 ISBN 580 34199 Amendments issued since publication Amd No Date Comments 13533 19 October 2001 Spelling error corrected on front cover EN 2892 EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM February 2000 ICS 77.1 80 English version Founding - Equipment for the production of lost patterns for the lost foam casting process Fonderie - Outillages pour la production de modèles perdus pour le procédé de moulage “lost foam” Gießereiwesen – Einrichtungen zur Herstellung von verlorenen Modellen für das Vollformgießverfahren This European Standard was approved by CEN on 25 December 999 CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member This European Standard exists in three official versions (English, French, German) A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom EUROPEAN COMMITTEE FOR STANDARDIZATION C O MITÉ EUROP ÉEN D E NO RMALIS ATIO N E U RO P Ä I S C H E S KO M I T E E F Ü R N O RM U N G Central Secretariat: rue de Stassart, 36 B-1 050 Brussels © 2000 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members Ref No EN 2892:2000 E Page EN 2892:2000 Contents Page Foreword Introduction Scope Normative references Terms and definitions 4.1 4.2 4.3 Order information and delivery conditions General Points to be discussed Mandatory information Classification 6.1 6.2 6.3 6.4 6.5 6.6 Specifications Drawings and/or numerical data and/or master patterns Designation Sub-contracted services Mass Tooling filling systems Tooling temperature 7.1 Manufacturing requirements Materials 7 Page 7.2 7.3 7.4 7.5 7.6 Manufacture Contractions Required machining allowances (RMA) Tolerances Marking and labelling 8.1 8.2 Quality control Inspection documentation Samples 9.1 9.2 9.3 9.4 9.5 13 13 13 14 14 Usage General Thermal stability Pressure (clamping and injection) Tooling handling Tooling location, connection and alignment 9.6 Pattern stripping and handling 9.7 Tooling assembly 9.8 Prevention of pattern distortion 9.9 Repair and refurbishment 9.1 Packaging and protection 9.1 Other requirements 10 12 12 13 13 14 14 14 14 14 14 14 Annex A (informative) Examples at a dimensional test report and a tooling checklist ? BSI October 2001 Page EN 2892:2000 Foreword This European Standard has been prepared by Technical Committee CEN/TC 90, Foundry technology, the secretariat of which is held by DIN This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by August 2000, and conflicting national standards shall be withdrawn at the latest by August 2000 According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom Within its programme of work, Technical Committee CEN/TC 90 requested CEN/TC 90/WG 30 "Production equipment, tools, foundry auxiliaries (e.g patterns, permanent moulds, moulding materials)" to prepare the following standard: EN 2892 Founding – Equipment for the production of lost patterns for the lost foam casting process This is one of three of European Standards for foundry patterns and tools The other standards are: prEN 2883 Founding – Equipment for the production of lost patterns for the lost wax casting process EN 2890 Founding – Patterns, pattern equipment and coreboxes for the production of sand moulds and sand cores ? BSI October 2001 Page EN 2892:2000 Introduction Lost pattern production processes involve the moulding of a pattern The pattern is then destroyed either prior to or during the casting process At present two processes are commonly used: – investment casting (lost wax process); – lost foam process This standard concerns the lost foam process This standard describes the specification for tooling to produce patterns or cores for the lost foam process This standard is intended for purchasers, manufacturers and founders It is also intended to ensure correct interpretation of part and tool drawings/numerical data, and to ensure pattern equipment will produce lost moulds and lost cores, suitable for use and to assist in determining the usually undefined limits of good workmanship It stresses the need for consultation between the founder, manufacturer (patterns), manufacturer (tooling) and purchaser before work commences This standard is intended to assist interested parties in producing tooling for urea or dense polystyrene or expanded material patterns suitable for use to produce castings by the lost pattern process There is a complex relationship between the parties who might be involved in specifying, manufacturing, ordering and designing the equipment within the scope of this standard NOTE: Figure gives an indication of the relationships that could exist between the four parties concerned Figure – M odel inter-relationships between the contracti ng parties This standard not only specifies the usual features of design, manufacture, materials, tolerances, contractions and required machining allowances but also specifies other features such as usage, classification, quality control, marking, packaging and storage ? BSI October 2001 Page EN 2892:2000 Scope This standard specifies the requirements for tooling for the production of lost patterns by the lost foam process Normative references This European Standard incorporates by dated or undated reference, provisions from other publications These normative references are cited at the appropriate places in the text and the publications are listed hereafter For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision For undated references the latest edition of the publication referred to applies EN 0204 Metallic products – Types of inspection documents EN 20286-1 ISO system of limits and fits – Part 1: Bases of tolerances, deviations and fits (ISO 286-1 :1 988) ISO 8062:1 994 Castings – System of dimensional tolerances and machining allowances Terms and definitions For the purposes of this standard, the following terms and definitions apply: 3.1 collapsible insert Part made in two or more pieces to permit withdrawal from an undercut pattern surface 3.2 contraction Provision applied to the tooling for shrinkage occurring during the production of castings 3.3 dowel register Component which ensures accuracy of fit or alignment between mating portions of the tooling 3.4 taper Draft angles on surfaces of tooling parts or lost patterns which enable the tooling parts or the lost patterns to be withdrawn 3.5 fixing One or more components which ensure that the parts of the tooling are held together securely and accurately 3.6 insert or loose piece Part which is removed by hand or by mechanical means from the pattern before or during stripping and is then repositioned in the tooling ? BSI October 2001 Page EN 2892:2000 3.7 lost foam process Pattern casting process in which a destructible pattern material is used NOTE: The pattern is surrounded by a heat resistant material prior to pouring 3.8 manufacturer (patterns) Person or body responsible for the manufacture of lost foam patterns 3.9 manufacturer (tooling) Person or body responsible for the manufacture of the tooling and/or ancillary equipment required to produce a lost foam pattern 3.1 master pattern Model used to produce a pattern which includes the appropriate contractions 3.1 mismatch Offset conditions at parting line caused by misalignment 3.1 pattern Foam based shaped material 3.1 pattern injection Process of filling the tooling cavity with expandable material 3.1 stripping Action of removing the pattern from the tooling by hand or by mechanical means 3.1 tooling All the equipment required for the production of a lost pattern (except the machine used to inject the foam) 3.1 tooling cavity Intended space in the tooling into which pattern material is introduced 3.1 tooling filling system Openings used to introduce the pattern material into the tooling ? BSI October 2001 Page EN 2892:2000 Order information and delivery conditions 4.1 General There shall have been an agreement made and an exchange of information carried out between the purchaser, the manufacturer (patterns), the manufacturer (tooling) and the founder by the time of acceptance of the order, to ensure a full understanding of the respective requirements of the parties concerned 4.2 Points to be discussed As applicable, the following essential points shall be considered during the negotiation stage: – casting material(s) and its (their) identification; – number of patterns to be produced; – number of sub-elements for each pattern; – pattern and/or core materials; – drawings and/or numerical data; – number of tooling cavities required; – contractions; – joint lines; – pattern joints; – tapers; – components and identification of tooling; – required machining allowances; – machining provisions and tooling finishing requirements; – tooling materials; – tooling quality class; – surface condition of the tooling cavity; – dimensional tolerances; – pattern stripping and cooling support systems; – tooling inspection requirements and inspection fixtures; – runner/feeder positions and, if necessary, the system; – tooling accessories; – assembly accessories; – any other important parameters such as surface protection and packaging for transport, storage, venting and assembling arrangements ? BSI October 2001 Page EN 2892:2000 4.3 Mandatory information The enquiry and order shall include information on: a) number of toolings to be supplied and the delivery requirements; b) specification(s) of the material(s) to be used in the manufacture of the tooling; c) relevant drawings and/or numerical data; d) contraction(s) to be used; e) size and position of any gating required; f) positions and sizes of blow holes for expanded material; g) information on tooling mounting, connection and alignment; h) surface condition required for the tooling cavity; i) inspection(s) and documentation required; j) relevant quality class; k) any functional tests required; and, as applicable: l) additional properties not specified in the material standards; m) special measures to be taken or specifications to be observed, particularly with regard to the testing of welds; n) repairs of tooling; o) type of protection and packaging; NOTE: Transport arrangements can be included p) approval procedures; q) storage arrangements; r) any other requirements Classification There shall be an agreement made between the parties concerned on the quality class to be adopted NOTE: Table gives guidance for the selection of metal pattern equipment ? BSI October 2001 Page EN 2892:2000 Table – M etal pattern equipmen t Features Use Manufacture Material Wearing parts Loose pieces Dimensional tolerances Quality class M5 Long run manufacture using foam injection machines and involving high standards Worked from solid material (machined) or cast to size and suitably finished Aluminium alloys, steels and other alloys See relevant material See relevant material In accordance with EN 20286-1 and ISO 8062:1 994 M6 Batchwise manufacture using foam injection machines and involving high standards As for M5, but finishing not as critical, alternatively made up from several parts As for M5 As for M5 As for M5 As for M5 Specifications 6.1 Drawings and/or numerical data and/or master patterns The purchaser shall make available to the manufacturer (tooling) any necessary drawings of the casting and/or numerical data and/or master patterns The identification of the relevant drawings and/or relevant numerical data and/or relevant master pattern(s) shall be specified in the enquiry and order The drawing(s) shall conform to European or International Standards unless otherwise agreed Any modifications to the drawings and/or numerical data and/or master patterns necessary to aid manufacture of the tooling shall, be agreed between the purchaser, the founder, the manufacturer (patterns) and the manufacturer (tooling) The manufacturer (tooling) shall be responsible for the shape, dimension and suitability of the tooling being manufactured 6.2 Designation The designation of the quality class on the drawings and other relevant documents shall contain the following: – the number of this European Standard (EN 2892); – the quality class EXAMPLE: EN 2892 – M5 6.3 Sub-contracted services If the manufacturer (tooling) intends to sub-contract design or engineering services, he shall obtain prior approval from the purchaser 6.4 Mass The design shall be such as to minimize the mass of the tooling to ease handling and preserve the integrity of the final geometry ? BSI October 2001 Page EN 2892:2000 6.5 Tooling filling systems Agreement shall be made on the size and location of any filling system used If it is not practicable to provide sketches of the gating system to the manufacturer (tooling), the area and size of the possible filling facility shall be given and the area shall be kept free from screws and dowels Tooling design shall make provision for space and joint line considerations to allow the filling system to be added at a later date 6.6 Tooling temperature If necessary, provision shall be made to ensure that the tooling temperature can be pre-set within a defined temperature range Provision shall be made to ensure that the completion of the expansion process is within defined temperature and time limits Manufacturing requirements 7.1 M aterials 7.1 General Materials used in the manufacture of tooling shall meet the conditions agreed by the parties concerned 7.1 Fixings All fixings shall be treated to prevent their corrosion or shall be corrosion resistant NOTE: Attention should be paid to the need to prevent bi-metallic corrosion 7.1 Inserts and sliding loose pieces Inserts and/or sliding loose pieces shall be made preferably from material different to that of the tooling case or frame to reduce friction 7.2 M anufacture 7.2.1 General The following requirements, as applicable, shall be met: a) mismatch shall be within the tolerances agreed by the parties concerned; b) elements of the tooling shall be designed such as to permit subsequent modifications; c) screws shall be lubricated to prevent seizing; d) working threads in aluminium alloys shall have reinforced inserts; e) wiping slots shall be provided on sliding surfaces to facilitate self-cleaning; f) all external corners or sharp edges on the tooling shall be chamfered or radiused Internal sharp corners forming the pattern and external sharp corners on the tooling shall be avoided unless otherwise specified The radius used shall be the maximum permitted ? BSI October 2001 Page 1 EN 2892:2000 7.2.2 J oint lines and glue joints 7.2.2.1 Position The position of joint line(s) shall be such as to prevent flash The position of the glue joints shall be such as to facilitate glueing NOTE: Joint lines and glue joints should not be positioned in areas where flatness is specified on the drawing 7.2.2.2 Venting Tooling cavities shall be vented: – to ensure their adequate filling; – to aid the stripping of the pattern; – to allow for the introduction of steam for the expansion process; – to optimize the density of the foam 7.2.3 Inserts and loose pieces 7.2.3.1 Securing methods Suitable means of securing shall be used Removable screws shall be clearly marked to facilitate their proper repositioning 7.2.3.2 Feather edges Feather edges shall be avoided generally in the tooling but specifically in the design of loose pieces 7.2.4 Location devices 7.2.4.1 General Location devices shall be designed so that the tooling can only be assembled in the intended sequence and position 7.2.4.2 Dowels Dowels shall be non-reversible If necessary, dowels shall be relieved 7.2.4.3 Guide pins, keys and machined shoulders Guide pins, keys and machined shoulders shall be provided as necessary to maintain alignment of tooling parts Any pin shall be both hardened and ground Any pin shall be tapered at its ends to facilitate closure of the tooling If applicable, such pins shall fit hardened drill bushings to ensure accurate closure of the tooling 7.2.4.4 Hinged tooling Hinged tooling shall be fitted with fixings that prevent movement in directions other than those which are intended ? BSI October 2001 Page EN 2892:2000 7.2.5 Radii and fillets Radii and fillets shall be incorporated to assist pattern removal Such provisions shall be agreed between the parties concerned 7.2.6 Other requirements 7.2.6.1 Multiple cores and multiple loose pieces Multiple cores and multiple loose pieces shall be provided with accurate and secure location in the tooling They shall be designed in such a way that their easy and safe withdrawal is facilitated They shall be identified with their proper position Their sequence and direction of withdrawal shall be indicated 7.2.6.2 Large cores If necessary, large cores shall be divided into two or more pieces Their surfaces, as appropriate, shall be tapered to aid withdrawal If required, means shall be provided to overcome suction 7.2.6.3 Blind cores If necessary, blind cores shall be vented to overcome suction and to assist in their removal 7.2.7 Tooling handling 7.2.7.1 General If necessary, finger grips or handles or lifting eye positions shall be provided 7.2.7.2 Hinged tooling Handles shall be provided on all hinged tooling The tooling shall be kept open with a safety locking device until it is deliberately released NOTE: Cams can be required on large tooling to overcome the suction on opening 7.2.8 Tooling finishing Tooling cavities shall be finished so as to remove all tool marks and to allow easy withdrawal of the pattern(s) 7.3 Contraction(s) The contraction(s) in the tooling shall be agreed between the parties concerned NOTE: The contraction(s) of the foam(s) and the contraction(s) of the casting(s) can vary across the three axes due to, for example, tooling material, alloy, metal temperature, casting design and mould material, etc 7.4 Required machining allowances (RMA) If an allowance in the tooling has to be made for machining of the subsequently produced casting, there shall be an agreement made between the parties concerned NOTE: ISO 8062:1 994 gives further information ? BSI October 2001 Page EN 2892:2000 7.5 Tolerances 7.5.1 General The tooling cavity dimensional tolerances shall be subject of an agreement between the parties concerned 7.5.2 Surface finish Surface finish shall be the subject of an agreement between the parties concerned by the time of acceptance of the order 7.6 Marking and labelling 7.6.1 General The tooling shall be marked for identification purposes after prior agreement between the parties concerned Marking shall be permanent and legible NOTE: Examples of desirable information that might form part of this marking or labelling are: a) drawing number and issue; b) foundry identification; c) contraction(s) or shrinkage(s); d) manufacturer (tooling) identification (name or logo); e) any other information requested by the purchaser 7.6.2 Multi-cavity tooling Each cavity shall be marked either in or adjacent to that cavity or on its ingate, as required Quality control 8.1 Inspection documentation The issue of inspection documentation shall be subject to an agreement between the parties concerned The requirements of EN 0204 shall be met Examples of specific test reports are given in annex A 8.2 Samples The provision of sample patterns and/or sample castings shall be the subject of an agreement between the parties concerned Usage 9.1 General The lifetime and suitability of tooling depend upon the quality class, the conditions of use and the conditions of storage 9.2 Thermal stability The tooling shall be capable of effective operation within the intended temperature range ? BSI October 2001 Page EN 2892:2000 9.3 Pressure (clamping and injection) The tooling shall be capable of effective operation at the intended pressure (clamping and injection) 9.4 Tooling handling The tooling shall be provided with the means to give ease of handling during usage and transportation 9.5 Tooling location, connection and alignment The tooling shall be provided with means to ensure its proper and safe location, its connection and its alignment to the machine (injection and/or expansion) The details to ensure this proper location shall be notified to the manufacturer (tooling) in writing 9.6 Pattern stripping and handling The tooling shall be provided with means to ensure proper stripping and handling of the pattern 9.7 Tooling assembly If necessary, the tooling shall be provided with the means to ensure its the ease of assembly All tooling parts shall be separately identified so that they can be properly assembled and disassembled If it is considered that the logical removal sequence of tooling parts, e.g loose pieces, inserts and metal cores, is not obvious, then an instruction sheet shall be provided which shows the sequence and direction of removal 9.8 Prevention of pattern distortion Provision shall be made to ensure that there is no distortion of the pattern(s) during stripping Provision shall also be made to ensure that there is no distortion of the pattern(s) during subsequent handling, storing and/or transportation when the means used to handle, store and/or transport the pattern(s) form part of the order 9.9 Repair and refurbishment Any repairs and/or refurbishment such as the plugging of holes, welding, the use of shims etc to correct nonconformances shall be permissible only with the agreement of the purchaser Drawings or sketches of tooling marked up with these corrections shall be submitted to the purchaser for approval in writing 9.1 Packaging and protection If applicable, suitable packaging and protection shall be provided 9.1 Other requirements If necessary, means such as for cooling, coating, drying, transportation, storage and setting, either for patterns or for tooling, shall be agreed by the time of acceptance of the order ? BSI October 2001 Page EN 2892:2000 Annex A (informative) Examples of a dimensional test report and a tooling checklist An example of a dimensional test report is given in Table A.1 An example of a tooling checklist is given in Table A.2 In the case of a tooling specification sheet, this should be supplied with all new toolings Table A.1 – Dimensional test report Dimensional test report Code number: Drawing number: Part number: Contraction: Tooling No Drawing dimension Contraction Tooling dimension Drawing issue number: Tooling dimension deviation Tooling dimension tolerance Comments Signature: Lost foam pattern No Drawing dimension Date: Contraction Lost foam pattern dimension Lost foam pattern dimension deviation Lost foam pattern dimension tolerance Comments Signature: Casting No Date: Drawing dimension Casting dimension Casting dimension deviation Casting dimension tolerance Comments Signature: Date: ? BSI October 2001 Page EN 2892:2000 Table A.2 – Tooling checklist Tooling checklist No 10 11 12 13 Subject Confirmation mark A dimensional test report has been carried out and supplied The part number, drawing issue number etc have been marked on the lost foam pattern – if required by the order A good lost foam pattern has been produced from the tooling Tooling stamped with identification as required by the order External corners of tooling chamfered or radiused Appropriate screws and dowels identified as required Tooling location points on the injection machine Handles, when required Finger grips and slots Drawing checked and applicable drawing notes confirmed All internal radii, if permitted Gating system incorporated *) Signature: Date: *) Additional items can be added with the agreement of the parties concerned ? BSI October 2001 blank BS EN 12892:2000 BSI — British Standards Institution BSI is the independent national body responsible for preparing British Standards It presents the UK view on standards in Europe and at the international level It is incorporated by Royal Charter Revisions British Standards are updated by amendment or revision Users of British Standards should make sure that they possess the latest amendments or editions It is the constant aim of BSI to improve the quality of our products and services We would be grateful if anyone finding an inaccuracy or ambiguity while using this British Standard would inform the Secretary of the technical committee responsible, the identity of which can be found on the inside front cover Tel: 020 8996 9000 Fax: 020 8996 7400 BSI offers members an individual updating service called PLUS which ensures that subscribers automatically receive the latest editions of standards Buying standards Orders for all BSI, international and foreign standards publications should be addressed to Customer Services Tel: 020 8996 9001 Fax: 020 8996 7001 Standards are also available from the BSI website at http://www.bsi-global.com In response to orders for international standards, it is BSI policy to supply the BSI implementation of those that have been published as British Standards, unless otherwise requested Information on standards BSI provides a wide range of information on national, European and international standards through its Library and its Technical Help to Exporters Service Various BSI electronic information services are also available which give details on all its products and services Contact the Information Centre Tel: 020 8996 7111 Fax: 020 8996 7048 Subscribing members of BSI are kept up to date with standards developments and receive substantial discounts on the purchase price of standards For details of these and other benefits contact Membership Administration Tel: 020 8996 7002 Fax: 020 8996 7001 Further information about BSI is available on the BSI website at http://www.bsi-global.com Copyright Copyright subsists in all BSI publications BSI also holds the copyright, in the UK, of the publications of the international standardization bodies Except as permitted under the Copyright, Designs and Patents Act 1988 no extract may be reproduced, stored in a retrieval system or transmitted in any form or by any means – electronic, photocopying, recording or otherwise – without prior written permission from BSI This does not preclude the free use, in the course of implementing the standard, of necessary details such as symbols, and size, type or grade designations If these details are to be used for any other purpose than implementation then the prior written permission of BSI must be obtained BSI 389 Chiswick High Road London W4 4AL If permission is granted, the terms may include royalty payments or a licensing agreement Details and advice can be obtained from the Copyright Manager Tel: 020 8996 7070

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