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BRITISH STANDARD BS EN756:2004Welding consumables—Solid wires, solidwire-flux and tubular cored electrode-flux combinations for submerged arc weldingof non alloy and finegrain steels— ClassificationThe European Standard EN 756:2004 has the status of aBritish StandardICS 25.160.2012 &23<,1* :,7+287 %6, 3(50,66,21 (;&(37 $6 3(50,77(' %< &23<5,*+7 /$:BS EN 756:2004This British Standard was published under the authority of the Standards Policy and Strategy Committee on 10March 2004© BSI 10March 2004ISBN 0 580 43546 6National forewordThis British Standard is the official English language version of EN 756:2004. It supersedes BS EN 756:1996 which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee WEE/39, Welding consumables, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary.Cross-referencesThe British Standards which implement international or Europeanpublications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard does not of itself confer immunity from legal obligations.—aid enquirers to understand the text;—present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the —Summary of pagesThis document comprises a front cover, an inside front cover, the EN title page, pages 2 to 12, an inside back cover and a back cover.The BSI copyright notice displayed in this document indicates when the document was last issued.Amendments issued since publication Amd. No.Date CommentsEUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORMEN 756March 2004ICS 25.160.20Supersedes EN 756:1995English versionWelding consumables - Solid wires, solid wire-flux and tubular cored electrode-flux combinations for submerged arc welding ofnon alloy and fine grain steels - ClassificationProduits consommables pour le soudage - Fils pleins,couples fils pleins-flux et fils fourrés-flux pour le soudage àl'arc sous flux des aciers non alliés et à grains fins -ClassificationSchweißzusätze - Massivdrähte, Fülldrähte undDrahtpulver-Kombinationen zum Unterpulverschweißen von unlegierten Stählen und Feinkornbaustählen - EinteilungThis European Standard was approved by CEN on 2 January 2004.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, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATION C O M I T É E U R O P ÉE N D E N O R M A LI S A T I O N C HES KOM ITEE FÜR NOR M UNG© 2004 CENAll rights of exploitation in any form and by any means reserved worldwide for CEN national Members.Ref. No. EN 756:2004: EEN 756:2004 (E)ContentsPage Foreword (3)Introduction (4)1Scope (5)2Normative references (5)3Classification (5)4Symbols and requirements (6)4.1Symbol for the process (6)4.2Symbol for the tensile properties (6)4.2.1Multi run technique (6)4.2.2Two-run technique (6)4.3Symbol for the impact properties of all-weld metal or two-run weldment (6)4.4Symbol for the type of welding flux (7)4.5Symbol for the chemical composition of solid wire electrodes or the all-weld metaldeposited by a tubular cored electrode-flux combinations (7)5Mechanical tests (9)5.1Multi run technique (9)5.2Two run technique (10)6Chemical analysis (10)7Technical delivery conditions (10)8Designation (10)Bibliography (12)2EN 756:2004 (E)ForewordThis document (EN 756:2004) has been prepared by Technical Committee CEN/TC 121 “Welding”, 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 September 2004, and conflicting national standards shall be withdrawn at the latest by September 2004.This document supersedes EN 756:1995.According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.3EN 756:2004 (E)IntroductionThis standard proposes a classification in order to designate solid wire electrodes by chemical analyses and solid wire-flux combinations in terms of the yield strength, tensile strength and elongation and impact properties of the all-weld metal. Tubular cored electrode-flux combinations are designated by the chemical composition; yield strength, tensile strength and elongation and impact properties of the all-weld metal. The ratio of yield to tensile strength of weld metal is generally higher than that of parent metal. Users should note that matching weld metal yield strength to parent metal yield strength will not necessarily ensure that the weld metal tensile strength matches that of the parent material. Where the application requires matching tensile strength, therefore, selection of the consumable should be made by reference to column 3 of Table 1.Although combinations of electrodes and fluxes supplied by individual companies may have the same grading, the individual electrodes and fluxes from different companies are not interchangeable unless verified according to this standard.It should be noted that the mechanical properties of all-weld metal test specimens used to classify the electrode-flux combinations will vary from those obtained in production joints because of differences in welding procedures such as electrode size and parent metal chemical composition.4EN 756:2004 (E)1 ScopeThis standard specifies requirements for classification of electrode-flux combinations and all-weld metal in the as-welded condition for submerged arc welding of non alloy and fine grain steels with a minimum yield strength of up to 500 MPa. Classification can be made with solid wire electrodes or tubular cored electrodes. One flux may be classified with different electrodes. The solid wire electrode is also classified separately based on its chemical composition. Fluxes for the single and two run techniques are classified on the basis of the two run technique.2 Normative referencesThis 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 European Standards only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies (including amendments).EN ISO 544, Welding consumables – Technical delivery conditions for welding filler materials – Type of product, dimensions, tolerances and markings (ISO 544:2003).EN 760, Welding consumables – Fluxes for submerged arc welding – Classification.EN 1597-1, Welding consumables - Test methods - Part 1: Test piece for all-weld metal test specimens in steel, nickel and nickel alloys.EN 1597-2, Welding consumables - Test methods - Part 2: Preparation of test piece for single-run and two-run technique test specimens in steel.EN ISO 6847, Welding consumables - Deposition of a weld metal pad for chemical analysis (ISO 6847:2000). EN ISO 13916, Welding – Guidance on the measurement of preheating temperature, interpass temperature and preheat maintenance temperature (ISO 13916:1996).ISO 31-0:1992, Quantities and units – Part 0: General principles.3 ClassificationThe classification includes all-weld metal properties obtained with a manufacturer's specific electrode-flux combination as given below. A solid wire electrode may be separately classified with the symbol for its chemical composition in Table 5.The classification is divided into five parts:1) The first part gives a symbol indicating the process to be identified.2) The second part gives a symbol indicating strength and elongation of all-weld metal for multi runtechnique or the strength of the parent material used in classification for the two run technique.3) The third part gives a symbol indicating impact properties of the all-weld metal or the two run weldedjoint.4) The fourth part gives a symbol indicating the type of flux used.5) The fifth part gives a symbol indicating the chemical composition of the solid wire electrode used or thechemical composition of the all-weld metal deposited by a tubular cored electrode-flux combination.5EN 756:2004 (E)64 Symbols and requirements4.1 Symbol for the processThe symbol for a solid wire electrode and/or an electrode-flux combination used in the submerged arc welding process shall be the letter S.4.2 Symbol for the tensile properties4.2.1 Multi run techniqueThe symbol in Table 1 indicates yield strength, tensile strength and elongation of the all-weld metal in the as-welded condition determined in accordance with 5.1.Table 1 — Symbol for tensile properties by multi run technique SymbolMinimumyield strengthaMPa Tensile strength MPa Minimum elongationb%35355440 to 5702238380470 to 6002042420500 to 6402046460530 to 6802050500560 to 72018a For yield strength the lower yield (R eL ) shall be used when yielding occurs, otherwise the 0,2 % proof strength (R pO,2) shall be used.bGauge length is equal to five times the specimen diameter.4.2.2 Two-run techniqueThe symbol indicates strength of the welded joint in relation to strength of the parent material used in two-run welding tests satisfactorily completed in accordance with 5.2.Table 2 — Symbol for the tensile properties by two-run technique SymbolMinimum parent material yield strength MPa Minimum tensile strength of the welded jointMPa 2T 2753703T 3554704T 4205205T5006004.3 Symbol for the impact properties of all-weld metal or two-run weldmentThe symbol in Table 3 indicates the temperature at which an average impact energy of 47 J is achieved under conditions given in clause 5. Three specimens shall be tested. Only one individual value may be lower than 47 J but not lower than 32 J. When an electrode-flux combination has been classified for a certain temperature, it automatically covers any higher temperature in Table 3.EN 756:2004 (E)Table 3 — Symbol for the impact properties of all-weld metal or two-run welded joint Symbol Temperature for minimum average impact energy of 47 J°CZ no requirementsA+20002-203-304-405-506-607-708-804.4 Symbol for the type of welding fluxThe symbol in Table 4 indicates the welding flux as described in EN 760.Table 4 — Symbol for the type of welding fluxType of flux SymbolManganese-silicate MSCalcium-silicate CSZirconium-silicate ZSRutile-silicate RSAluminate-rutile ARAluminate-basic ABAluminate-silicate ASAluminate-fluoride-basic AFFluoride-basic FBAny other type Z4.5 Symbol for the chemical composition of solid wire electrodes or the all-weld metal deposited by a tubular cored electrode-flux combinationsThe symbol in Table 5 indicates the chemical composition of the solid wire electrode and includes an indication of characteristic alloying elements.The symbol in Table 6 indicates the chemical composition of the all-weld metal deposited by a tubular cored electrode-flux combination carried out according to Table 7.The chemical composition of the weld metal is dependent on the chemical composition of the solid wire electrode or tubular cored electrode and the metallurgical behaviour of the flux (see EN 760).7E N 756:2004 (E )8T a b l e 5 — C h e m i c a l c o m p o s i t i o n o f s o l i d w i r e e l e c t r o d e s f o r s u b m e r g e d a r c w e l d i n gC h e m i c a l c o m p o s i t i o n (%) (m /m )ab cS y m b o lC S i M nPS M o N i C rC uS Z a n y o t h e r a g r e e d c o m p o s i t i o n S 10,05 t o 0,150,150,35 t o 0,600,0250,0250,150,150,150,30S 20,07 t o 0,150,150,80 t o 1,300,0250,0250,150,150,150,30S 30,07 t o 0,150,151,30 t o 1,750,0250,0250,150,150,150,30S 40,07 t o 0,150,151,75 t o 2,250,0250,0250,150,150,150,30S 1S i 0,07 t o 0,150,15 t o 0,400,35 t o 0,600,0250,0250,150,150,150,30S 2S i 0,07 t o 0,150,15 t o 0,400,80 t o 1,300,0250,0250,150,150,150,30S 2S i 20,07 t o 0,150,40 t o 0,600,80 t o 1,300,0250,0250,150,150,150,30S 3S i 0,07 t o 0,150,15 t o 0,401,30 t o 1,850,0250,0250,150,150,150,30S 4S i 0,07 t o 0,150,15 t o 0,401,85 t o 2,250,0250,0250,150,150,150,30S 1M o 0,05 t o 0,150,05 t o 0,250,35 t o 0,600,0250,0250,45 t o 0,650,150,150,30S 2M o 0,07 t o 0,150,05 t o 0,250,80 t o 1,300,0250,0250,45 t o 0,650,150,150,30S 3M o 0,07 t o 0,150,05 t o 0,251,30 t o 1,750,0250,0250,45 t o 0,650,150,150,30S 4M o 0,07 t o 0,150,05 t o 0,251,75 t o 2,250,0250,0250,45 t o 0,650,150,150,30S 2N i 10,07 t o 0,150,05 t o 0,250,80 t o 1,300,0200,0200,150,80 t o 1,200,150,30S 2N i 1,50,07 t o 0,150,05 t o 0,250,80 t o 1,300,0200,0200,151,20 t o 1,800,150,30S 2N i 20,07 t o 0,150,05 t o 0,250,80 t o 1,300,0200,0200,151,80 t o 2,400,150,30S 2N i 30,07 t o 0,150,05 t o 0,250,80 t o 1,300,0200,0200,152,80 t o 3,700,150,30S 2N i 1M o 0,07 t o 0,150,05 t o 0,250,80 t o 1,300,0200,0200,45 t o 0,650,80 t o 1,200,200,30S 3N i 1,50,07 t o 0,150,05 t o 0,251,30 t o 1,700,0200,0200,151,20 t o 1,800,200,30S 3N i 1M o 0,07 t o 0,150,05 t o 0,251,30 t o 1,800,0200,0200,45 t o 0,650,80 t o 1,200,200,30S 3N i 1,5M o 0,07 t o 0,150,05 t o 0,251,20 t o 1,800,0200,0200,30 t o 0,501,20 t o 1,800,200,30S 2N i 1C u 0,08 t o 0,120,15 t o 0,350,70 t o 1,200,0200,0200,150,65 t o 0,900,400,40 t o 0,65S 3N i 1C u 0,05 t o 0,150,15 t o 0,401,20 t o 1,700,0250,0250,150,60 t o 1,200,150,30 t o 0,60a F i n i s h e d p r o d u c t c h e m i c a l c o m p o s i t i o n , C u i n c l u s i v e o f c o p p e r c o a t i n g , A l ≤ 0,030 %.b S i n g l e v a l u e s s h o w n i n t h e T a b l e m e a n m a x i m u m v a l u e s .c T h e r e s u l t s s h a l l b e r o u nde d t o t h e s a m e n u m b e r of s ig n i f i c a n t f i g u r e s a s i n th e s p e ci f i e d v a l u e u s i n g t h e r u l e s i n a c c o r d a n c e w i t h a n n e x B , R u l e A o f I S O 31-0:1992.EN 756:2004 (E)9Table 6 — Chemical composition of the all-weld metal deposited by a tubular cored electrode-fluxcombination Chemical composition % (m/m)a bcSymbolMn Ni Mo CuT21,4--0,3T31,4 to 2,0--0,3T2Mo 1,4-0,3 to 0,60,3T3Mo 1,4 to 2,0-0,3 to 0,60,3T2Ni11,40,6 to 1,2-0,3T2Ni1,51,61,2 to 1,8-0,3T2Ni21,41,8 to 2,6-0,3T2Ni31,42,6 to 3,8-0,3T3Ni11,4 to 2,00,6 to 1,2-0,3T2Ni1Mo 1,40,6 to 1,20,3 to 0,60,3T2Ni1Cu 1,40,8 to 1,2-0,3 to 0,6TZany other agreed compositiona If not specified Mo ≤ 0,2 %, Ni ≤ 0,5 %, Cr ≤ 0,2 %, V ≤ 0,08 %, Nb ≤ 0,05 %, C 0,03 % to 0,15 %, Si ≤ 0,8 %, S ≤ 0,025 %,P ≤ 0,025 %.b Single values shown in the Table mean maximum values.cThe results shall be rounded to the same number of significant figures as in the specified value using the rules in accordance with annex B, Rule A of ISO 31-0:1992.5 Mechanical tests5.1 Multi run techniqueTensile and impact tests and any required retests shall be carried out on weld metal in the as-welded condition using an all-weld metal test assembly type 3 according to EN 1597-1 using 4,0 mm or 3,2 mm (3,0 mm; 2,8 mm)diameter electrodes which ever is the larger size being supplied.Welding conditions (single electrode welding) and details of the test assembly shall be selected from Table 7.Preheating is not required; welding may start from room temperature.The interpass temperature shall be measured using temperature indicator crayons, surface thermometers or thermocouples (see EN ISO 13916).The interpass temperature shall not exceed the interpass temperature indicated in Table 7. If, after any pass, the interpass temperature is exceeded, the test assembly shall be cooled in air to a temperature within the indicated range.Table 7 — Welding conditions for multi run single wire weldingSolid wire electrode diameter (mm)Cored wire electrode diameter(mm)Conditionsa2,8 to 3,24,03,0 to 3,24,0Length of weld deposit (mm)min. 350min. 350min. 350min. 350Type of current direct current bWelding current (A)440 ± 20580 ± 20480 ± 20550 ± 20Welding voltage (V)27 ± 129 ± 130 ± 130 ± 1Welding speed (mm/min)400 ± 50550 ± 50450 ± 50450 ± 50Interpass temperature (°C) (no preheat)150 ± 25150 ± 25150 ± 25150 ± 25Electrode extension (mm)30 ± 530 ± 530 ± 530 ± 5aIf alternating current and direct current operations are claimed; test welding shall be carried out using alternatingcurrent only.bDirect current welding polarity shall follow the recommendation of the manufacturer.EN 756:2004 (E)5.2 Two run techniqueTensile and impact tests and any required retests shall be carried out on weld metal in the as-welded condition using a test assembly type 4 according to EN 1597-2. Welding conditions shall be within the range recommended by the manufacturer and shall be recorded to demonstrate compliance with this standard.6 Chemical analysisChemical analysis shall be performed on specimens of the solid wire electrode or on any suitable all-weld metal test specimen deposited by the electrode-flux combination. In case of dispute specimens in accordance with EN ISO 6847 shall be used. Any analytical technique can be used, but in case of dispute reference shall be made to established published methods.NOTE See Bibliography.7 Technical delivery conditionsTechnical delivery conditions shall meet the requirements in EN ISO 544.8 DesignationThe designation of the solid wire electrode and the electrode-flux combination shall follow the principle given in the examples below:EXAMPLE 1 A wire-flux combination for submerged arc welding for multi run technique deposits a weld metal with a minimum yield strength of 460 MPa (46) and a minimum average impact energy of 47 J at -30°C (3) produced with an aluminate-basic flux (AB) and a solid wire electrode S2 is designated:Wire-flux combination EN 756 - S 46 3 AB S2where:EN 756= standard numberS= submerged arc welding (see 4.1)46= tensile properties (see Table 1)3= impact properties (see Table 3)AB= type of welding flux (see Table 4)S2= chemical composition (see Table 5)EXAMPLE 2 A wire-flux combination for submerged arc welding using two run technique demonstrated in accordance with the manufacturer's recommendation in a parent metal with minimum yield strength 420 MPa (4T) achieving a weld metal with transverse tensile strength > 520 MPa and impact energy 47J at -20°C (2) with an aluminate-basic flux (AB) and a solid wire electrode S2Mo is designated:Wire-flux combination EN 756 - S 4T 2 AB S2Mowhere:EN 756= standard number;S= submerged arc welding (see 4.1)4T= tensile properties (see Table 2)2= impact properties (see Table 3)AB= type of welding flux (see Table 4)S2Mo= chemical composition (see Table 5)10EN 756:2004 (E)EXAMPLE 3 A solid wire electrode complying with the chemical requirement of S2Mo in Table 5 is designated: Solid wire electrode EN 756 - S2MoEXAMPLE 4 A tubular cored electrode-flux combination for submerged arc welding for multi run technique deposits a weld metal with a minimum yield strength of 420 MPa (42) and a minimum average impact energy of 47 J at -20°C (2) produced with an aluminate-basic flux (AB) and the all-weld metal chemical composition T3Mo, is designated:Tubular cored electrode-flux combination EN 756 - S 42 2 AB T3Mowhere:EN 756= standard numberS= submerged arc welding (see 4.1)42= tensile properties (see Table 1)2= impact properties (see Table 3)AB= type of welding flux (see Table 4)T3Mo= chemical composition (see Table 6)11EN 756:2004 (E)12BibliographyHandbuch für das Eisenhüttenlaboratorium, VdEh, Düsseldorf.BS 6200-3, Sampling and analysis of iron, steel and other ferrous metals. Methods of analysis. Summary of methods. CR 10261, ECISS Information Circular 11 - Iron and steel - Review of available methods of chemical analysis.blankBS EN 756:2004BSI389 Chiswick High Road London W4 4ALBSI —British Standards InstitutionBSI is the independent national body responsible for preparingBritish Standards. It presents the UK view on standards in Europe and at the international level. It is incorporated by Royal Charter.RevisionsBritish Standards are updated by amendment or revision. Users ofBritish Standards should make sure that they possess the latest amendments or editions.Tel:+44+44(0)2089967400.BSI offers members an individual updating service called PLUS which ensures that subscribers automatically receive the latest editions of standards.Buying standardsOrders for all BSI, international and foreign standards publications should be addressed to Customer Services. Tel:+44(0)2089969001.Fax:+44(0)2089967001. Email:orders@. 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稀土基本知识目录一、稀土概述 (3)1.1 稀土的定义与分类 (4)1.2 稀土在元素周期表中的位置 (5)1.3 稀土元素的性质与应用 (5)二、稀土元素简介 (6)2.1 镧系元素 (9)2.2 铽系元素 (10)2.3 钇系元素 (11)2.4 铌系元素 (12)2.5 钼系元素 (13)三、稀土矿床类型及特点 (14)3.1 水源型矿床 (15)3.2 磁性地层型矿床 (17)3.3 热液型矿床 (18)3.4 混合型矿床 (19)四、稀土提取工艺 (20)4.1 重选法 (21)4.2 浮选法 (22)4.3 磁选法 (23)4.4 电选法 (25)4.5 化学选矿法 (26)五、稀土金属的制备 (27)5.1 熔炼法 (28)5.2 合金化法 (29)5.3 离子交换法 (30)5.4 湿法冶金法 (31)六、稀土材料及其应用 (32)6.1 稀土永磁材料 (33)6.2 稀土发光材料 (34)6.3 稀土催化材料 (36)6.4 稀土储氢材料 (37)七、稀土在高科技领域的应用 (38)7.1 稀土在信息技术中的应用 (39)7.2 稀土在新能源、环保领域的应用 (40)7.3 稀土在生物医学、农业领域的应用 (41)八、稀土资源保护与可持续发展 (42)8.1 稀土资源的现状与面临的问题 (43)8.2 稀土资源的保护和合理利用 (44)8.3 稀土产业的绿色转型与可持续发展 (45)一、稀土概述也称为镧系元素和钇族元素，包括17种化学元素：镧（La）、铈（Ce）、镨（Pr）、钕（Nd）、钐（Sm）、铕（Eu）、钆（Gd）、铽（Tb）、镝（Dy）、钬（Ho）、铒（Er）、铥（Tm）、钇（Y）、镱（Yb）和镥（Lu）。
这些元素在自然界中通常以矿石的形式存在，如独居石、氟碳铈矿等。
稀土元素在地壳中的分布不均，但在某些地区，如中国、美国和印度，它们的储量相对丰富。
稀土元素具有独特的物理和化学性质，如荧光性、磁性、催化活性和电导性等，这使得它们在许多高科技领域具有重要的应用价值。
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A、红光-蓝光的LED芯片B、高亮度车灯D、高亮度背投电视E、高亮度影院3、AI Day上“擎天往”演示了浇花、搬运纸箱、金属块等工作，能够很好地完成（）等动作，研发团队也在不断更新优化，有望在未来解锁更多应用场景。
B、视觉识别C、抓握D、下蹲E、直立行走4、下列关于各储能技术的说法中，错误的是（）。
D、压缩空气储能优点在转换率较高，响应速度较快E、超导储能优点在于容量大、便于长时间储存5、显示领域的发展趋势有（）。
C、新兴技术量产进程不断加快D、知识产权成为竞争新高地E、产业链上下游合作进一步加强三、判断题（共5题，每题6分）1、电子信息产业发展要转变观念，推动价值链式招商布局。
错误2、硅光器件虽然产业标准已经统一，但参数优化仍然有大量的工作要做。
错误3、集成电路=半导体=芯片。
错误4、全球二氧化碳排放量与全球温度变化呈现负相关态势，随着工业化、城镇化进程的推进，全球碳排放量正急剧增长。
错误5、电子信息产业指为了实现制作、加工、处理、传播或接收信息等功能或目的，利用电子技术和信息技术所从事的与电子信息产品相关的设备生产、硬件制造、系统集成、软件开发以及应用服务等软硬件的集合。
毕业设计（论文）题目丙烯酸甲酯制备工艺流程姓名所在系部专业班级指导教师年月l 丙烯酸甲酯制备工艺流程专业：高聚物生产技术学生指导老师摘要：作为有机合成中间体，也是合成高分子聚合物的单体，用于橡胶、医药、皮革、造纸、粘合剂等。
丙烯酸甲酯拥有很强的功用。
工艺描述:丙烯酸甲酯是由粗丙烯酸和甲醇在作为酸性酯化催化剂的硫酸存在下直接生产。
反应热约为-25.1KJ/mol，即酯化反应只是轻微的放热反应，反应物开始反应时不会出现剧烈的反应。
相反，会形成一个平衡的混合物，其中除了需要的产物，还存在相当数量的原料。
为了加速这个典型的平衡反应，得到需要的产物，通过蒸馏不断地从反应系统中移去两个反应产物，水和丙烯酸甲酯，蒸馏塔塔顶物中含有没反应的甲醇被回收，没反应的丙烯酸甲酯留在酯化反应器中。
酯化反应在均态液相下进行，既不需要有机溶剂，也不需要搅拌。
通过蒸馏分离出高纯度丙烯酸甲酯。
将甲醇、（来自甲醇回收塔C5200 和罐区）硫酸、（来自罐区）成品塔C5500 底部馏分和（来自罐区）加化学处理剂联氨改性的粗丙烯酸送入酯化反应器R5010 中。
来自甲醇回收塔5200 的新鲜及循环甲醇，以气态进入R5010；然后，塔顶物（丙烯酸甲酯，水，轻组分）被送到抽提塔（C5100）在C5100，用工艺水洗去甲醇，被洗过的丙烯酸甲酯从底部去抽提塔分离器V5110，底部物流送醇回收塔C5200，在C5200 中轻组分从顶部蒸出，回收的醇送回C5200。
基本没有有机物的水冷却后用作抽提塔C5100 的循，也作为酯化塔环水，多余的通过废水罐送废水处理厂。
分离器V5110 中的粗酯被送往初馏塔（C5300）的回流。
少量含有丙烯酸甲酯的初馏塔塔顶低沸物在冷凝器E5330 中冷凝并收集在相分离器V5340 中。
有机相的大部分在塔上部温度控制下作为回流返回初馏塔C5300，一小部分有机相通过容器V5460 送初馏物蒸馏塔C5400，以得到合格产品。
