1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationIndustrial electroheating equipment Test methods for direct arc furnacesBS EN 60676:2012National forewordThis British Standard is the UK implementation of EN 60676:2012. It is id
2、entical to IEC 60676:2011. It supersedes BS EN 60676:2002 which is withdrawn.The UK participation in its preparation was entrusted to Technical CommitteePEL/27, Electroheating.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not p
3、urport to include all the necessary provisions of acontract. Users are responsible for its correct application. The British Standards Institution 2012Published by BSI Standards Limited 2012ISBN 978 0 580 72080 2ICS 25.180.10Compliance with a British Standard cannot confer immunity fromlegal obligati
4、ons.This British Standard was published under the authority of the StandardsPolicy and Strategy Committee on 29 February 2012.Amendments issued since publicationAmd. No. Date Text affectedBRITISH STANDARDBS EN 60676:2012EUROPEAN STANDARD EN 60676 NORME EUROPENNE EUROPISCHE NORM February 2012 CENELEC
5、 European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Management Centre: Avenue Marnix 17, B - 1000 Brussels 2012 CENELEC - All rights of exploitation in any form and by any means reserved worldwide f
6、or CENELEC members. Ref. No. EN 60676:2012 E ICS 25.180.10 Supersedes EN 60676:2002English version Industrial electroheating equipment - Test methods for direct arc furnaces (IEC 60676:2011) Chauffage lectrique industriel - Mthodes dessai des fours arc direct (CEI 60676:2011) Industrielle Elektrowrm
7、eanlagen - Prfverfahren fr Lichtbogen-Schmelzfen(IEC 60676:2011) This European Standard was approved by CENELEC on 2011-12-13. CENELEC 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 stand
8、ard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version i
9、n any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croa
10、tia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 60676:
11、2012EN 60676:2012 - 2 - Foreword The text of document 27/816/FDIS, future edition 3 of IEC 60676, prepared by IEC/TC 27 “Industrial electroheating“ was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as EN 60676:2012. The following dates are fixed: latest date by which the documen
12、t has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2012-09-13 latest date by which the national standards conflicting with the document have to be withdrawn (dow) 2014-12-13 This document supersedes EN 60676:2002. EN 60676:2012 includes
13、 the following significant technical changes with respect to EN 60676:2002: Clause 1 (Scope and object) types of furnaces are more clearly defined. Clause 2 (Normative references) and Clause 3 (Terms and definitions) have been updated and completed. New Clause 4 (Features of the EAFsystem) has been
14、added; it mainly concentrates on the tests necessary for high-voltage / high-current electrical equipment in the installation. Clause 5 (Type of tests and general conditions of their performance) and Clause 6 (Technical tests) have been modified according to todays requirements for safe operation of
15、 an EAF. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CENELEC and/or CEN shall not be held responsible for identifying any or all such patent rights. Endorsement notice The text of the International Standard IEC 60676:2011 was
16、approved by CENELEC as a European Standard without any modification. In the official version, for Bibliography, the following notes have to be added for the standards indicated: 2 IEC 60146-1-1:2009 NOTE Harmonized as EN 60146-1-1:2010 (not modified). 3 IEC 60683:2011 NOTE Harmonized as EN 60683:201
17、2 (not modified). BS EN 60676:2012- 3 - EN 60676:2012 Annex ZA (normative) Normative references to international publications with their corresponding European publications The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its applica
18、tion. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies. Publ
19、ication Year Title EN/HD Year IEC 60398 1999 Industrial electroheating installations - General test methods EN 60398 1999 IEC 60519-1 - Safety in electroheating installations - Part 1: General requirements EN 60519-1 - IEC 60519-4 - Safety in electroheat installations - Part 4: Particular requiremen
20、ts for arc furnace installations EN 60519-4 - BS EN 60676:2012 2 60676 IEC:2011 CONTENTS 1 Scope and object 5 2 Normative references . 5 3 Terms and definitions . 5 4 Features of the EAF system . 9 4.1 General . 9 4.2 Electrical assembly of EAF 9 4.3 Furnace construction . 9 4.4 Water cooling 10 5 T
21、ype of tests and general conditions of their performance 10 5.1 General . 10 5.2 List of tests during cold and hot state 10 6 Technical tests . 11 6.1 Electrical insulation of high-current system 11 6.1.1 General . 11 6.1.2 Insulation resistance 11 6.2 Cooling water system 11 6.3 Electrode motion sp
22、eed . 12 6.4 Short-circuit test procedures 12 6.4.1 General . 12 6.4.2 High current system: resistance and reactance of EAFac 12 6.4.3 Test procedures 12 6.4.4 Asymmetry factor. 16 6.5 Main characteristics of EAF during production . 16 6.5.1 General . 16 6.5.2 Test procedures 16 6.6 Electrode consum
23、ption 17 6.7 Phase rotation . 18 6.8 EAF Rated capacity 18 Bibliography 19 Figure 1 Wiring diagram for measuring electrical data of the high current system to determine the resistance and reactance values . 13 BS EN 60676:201260676 IEC:2011 5 INDUSTRIAL ELECTROHEATING EQUIPMENT TEST METHODS FOR DIRE
24、CT ARC FURNACES 1 Scope and object This International Standard specifies test procedures, conditions and methods according to which the main parameters and the main operational characteristics of electric arc furnaces (EAF) operated either with alternating current (EAFac) or with direct current (EAF
25、dc) with a capacity above 500 kg/heat are established. The EAF technology is also applicable to furnaces, in which liquid metal is kept at high temperature or superheated to casting temperature (e.g. in a ladle furnace (LF), operated with alternating current). Test methods for some special equipment
26、, e.g. controlled rectifiers for EAFdc, are covered by IEC 60146-1-1. Test methods for submerged arc furnaces (SAF) are covered by IEC 60683. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited
27、 applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60398:1999, Industrial electroheating installations General test methods IEC 60519-1, Safety in electroheating installations Part 1: General requirements IEC 60519-4, Safety in ele
28、ctroheat installations Part 4: Particular requirements for arc furnace installations 3 Terms and definitions For the purposes of this document the terms and definitions given in IEC 60519-1:2010 and the following apply. NOTE Refer to International Electrotechnical Vocabulary, IEC 600500, for general
29、 definitions. Terms relating to industrial electroheat are defined in IEC 60050-841. 3.1active power P mean value of the instantaneous power p (in kW) taken under periodic conditions over one period of time T (in h): dtpTPT=01NOTE Active power instantaneous value (r.m.s.) measured at any time, inclu
30、ding all phases. IEC 60050-131:2002, 131-11-42, modified BS EN 60676:2012 6 60676 IEC:2011 3.2apparent power S power rating of the transformer, energizing the EAF (in MVA) UIS 3=(for three-phase EAF) where U is the voltage, r.m.s., sinusoidal value in kV I is the current, r.m.s. sinusoidal value in
31、KA IEC 60050-131:2002, 131-11-41, modified 3.3arc furnace furnace with a vessel, in which a metallic charge is heated mainly by electric arc using alternating current (EAFac) or direct current (EAFdc) IEC 60050-841:2004, 841-26-05, modified 3.4arc furnace transformer transformer changing medium/high
32、 voltage electrical supply to low voltage and high current for an EAF IEC 60050-841:2004, 841-26-55, modified 3.5asymmetry factor K difference between maximum and minimum impedance of any phase, divided by the mean impedance of all three phases (in %) NOTE Not applicable for EAFdc. 3.6capacity (of E
33、AF) volume of liquid material, which can be produced in the EAF (in t) NOTE Whether metric or short tonnes according to pre-requisites. IEC 60050-841:2004, 841-21-40, modified 3.7cold state (of EAF installation) thermal state of EAF installation when the temperature of all parts equals the ambient t
34、emperature 3.8electric arc furnace using alternating current EAFac furnace, in which electric arcs between the electrodes and the process material are formed, using three-phase alternating current NOTE Ladle furnace (LF) is operated under the same conditions. IEC 60050-841:2004, 841-26-07, modified
35、BS EN 60676:201260676 IEC:2011 7 3.9electric arc furnace using direct current EAFdc furnace, in which the direct current is induced via a bottom electrode (anode) to the material to be processed, forming arcs between the material and the electrode from top (cathode) IEC 60050-841:2004, 841-26-06, mo
36、dified 3.10EAF electrode part produced from high density graphite to transfer the electrical energy forming arcs between tip and charge material NOTE In EAFdc, a bottom electrode (anode) is metallic or conductive material in the bottom of an EAF and arcs are formed between the charge material and th
37、e graphite electrode from top (cathode). IEC 60050-841:2004, 841-26-38, modified 3.11electrode clamp metallic, water cooled equipment to hold the electrode and supply current for arcing to the electrode IEC 60050-841:2004, 841-26-39, modified 3.12heat mass of liquid material which is tapped after on
38、e process from an EAF into a ladle (in t) 3.13high-current line assembly to conduct the high current between transformer secondary bushings and electrode(s) of an EAF NOTE It consists of the bus bar system, cables and either a current tube system or current conducting electrode arm to the electrodes
39、. IEC 60050-841:2004, 841-26-54, modified 3.14hot state (of EAF) thermal state of an EAF in which the components and charge material are at a temperature above 600 C and a steady-state temperature of the components is reached 3.15medium/high-voltage switchgear medium/high-voltage switchgear connecti
40、ng the EAF transformer to the electrical supply by switching on/off under load NOTE EAF circuit switchgear capable for up to 150 operations under load per day. 3.16operational short circuit short circuit due to direct contact of at least two electrodes in an EAFac with charge/liquid material NOTE In
41、 EAFdc, short circuit is reached if the electrode from top is in contact with the charge/liquid material. IEC 60050-841:2004, 841-26-70, modified BS EN 60676:2012 8 60676 IEC:2011 3.17phase rotation phase sequence of the electromagnetic field (counter clock wise seen from top of the furnace) 3.18pow
42、er factor cos ratio of the active power to the apparent power measured on the primary side of the transformer SP= cos where P is the active power in MW S is the apparent power in MVA NOTE In case of harmonics, power factor is determined according to IEC 60146-1-1. 3.19power-on time (time p-on) time
43、(in min) between first arcing and tapping, in which the electrodes are under current 3.20production rate total quantity of metal (in t) tapped, divided by the tap-to-tap time (in h) 3.21reactive power Q total reactive electrical power (in MVAr) used in the system, measured on the primary side of the
44、 transformer IEC 60050-131:2002, 131-11-44, modified 3.22rectifier for direct current device by means of which alternating current is transferred into direct current for EAFdc 3.23reactor reactor connected in series to the EAFac transformer to minimise impacts on the electrical supply created by the
45、 arcs and ensure arc stability during the process 3.24shell body of EAF made from steel and covered by a roof IEC 60050-841:2004, 841-26-20, modified 3.25smoothing choke (shunt reactor) inductor smoothing electrical high frequency fluctuations in d.c. technology, due to changes in arc conditions NOT
46、E In case multiple rectifiers are coupled in the system, inductors can decrease the fluctuations as well. BS EN 60676:201260676 IEC:2011 9 3.26specific electrical energy consumption quotient of electrical energy consumed (in kWh) during melting and superheating of the metal (in t) tapped at a specif
47、ied temperature IEC 60050-841:2004, 841-22-72, modified 3.27tap-to-tap time tttttime (in min) between end of tapping of previous heat and end of tapping of actual heat 4 Features of the EAF system General 4.1In the EAF ferrous metal (e.g. steel or liquid iron) or non-ferrous metal (e.g. copper, nick
48、el or corundum etc.) can be produced. The EAF can be charged with solid or liquid material. Electrical assembly of EAF 4.2In the electrical assembly of an EAF the following equipment is included: a) main circuit, i.e.: medium/high voltage supply line including switchgear, reactive power compensation
49、 (if applicable), alternating current series reactor (if applicable), EAF transformer, high current bus bar system, high current cables, electrode arm system, EAFdc: controlled rectifier and shunt reactor for direct current, EAFac: three graphite electrodes from top, EAFdc: specific electrode(s) in the bottom and graphite electrode(s) from top; b) equipment to control all electrical parameters of the installation (i.e. boards,
