冰箱抽屉的模具设计
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编号 毕业论文题 目冰箱冰箱抽屉的模具设计学生姓名学 号系 部专 业班 级指导教师顾问教师 摘要摘 要塑料工业是当今世界上增长最快的工业门类之一,而注塑模具是其中发展较快的种类。随着现代工业发展的需要,塑料制品在工业、农业和日常生活等各个领域的应用越来越广泛,质量要求也越来越高。在塑料制品的生产中,高质量的模具设计、先进的模具制造设备、合理的加工工艺、优质的模具材料和现代化的成型设备等都是成形优质塑件的重要条件。本文完成冰箱抽屉塑料模具的设计,通过对冰箱抽屉的工艺性分析,设计了一副一模一腔的的塑料模具,包括塑件结构的分析和材料的选择、拟定模具结构形式、注塑机型号的选择、浇注系统的形式和浇口的设计、成型零件的设计、模架的确定和标准件的选用、合模导向机构的确定、脱模推出机构的确定、排气系统的设计、温度调节系统设计、注射模具选材、模具工作过程等,并且综合运用CAD/CAM系统标准软件UG的注塑模设计模块和autoCAD建立较简单零件的零件库。通过本次设计,对注塑模具有一定的认识,同时了解到设计中的某些细节问题及模具结构和模具工作原理,从而有效的提高工作效率。关键词:冰箱抽屉 CAD 注射模具ABSTRACTThe plastics industry is one of the fastest growing industries in the world, and the plastic injection mold is a kind of fast development. With the development of modern industry, the application of plastic products in various fields such as industry, agriculture and daily life is more and more extensive, and the quality requirement is higher and higher. In the production of plastic products, the high quality of mold design, advanced mold manufacturing equipment, the reasonable processing technology, high-quality mold material and modernization of injection molding equipment are forming an important condition for high-quality plastic parts.This paper completes the design of refrigerator drawer plastic mold, through process analysis of the refrigerator drawer, a pair of a mold cavity of the plastic mold design, including the structural analysis of plastic parts and materials selection, preparation of the mold structure, injection molding machine models of gating system and form the gate design, molding parts the design, mold and determine the selection of standard parts, mold oriented institutions, stripping institutions, exhaust system design, temperature control system design, injection mold material, mold working process, and the comprehensive use of the standard CAD/CAM system software UG injection mold design module and the establishment of autoCAD parts library is relatively simple part. Through the design and the injection mold has a certain understanding, as well as to the design of some details and mold structure and working principle, so as to effectively improve the work efficiency.Key words: refrigerator drawer CAD injection moldI目录目 录摘 要I目 录I第一章 绪 论11.1 模具工业在国民经济中的地位11.2 各种模具的分类和占有量11.3 中国模具发展现状21.4 课题的选择2第二章 塑件的材料选择及注射成型32.1制品的材料选择依据32.1.1 PS 聚苯乙烯的性能32.2注射机类型的选择42.3注射机有关工艺参数的校核52.3.1注射量的校核52.3.2锁模压力的校核52.3.3注射压力的校核52.3.4注射速率62.3.5模具闭合厚度的校核6第三章 成型零件的设计73.1型腔分型面的设计73.1.1 塑件在型腔中方位的选择73.1.2 分型面形状的选择73.1.3 分型面位置的选择73.2排气槽的设计83.3型腔结构设计83.3.1型腔内径尺寸计算83.3.2型腔深度尺寸计算93.3.3型腔壁厚与底板厚计算93.3.4型芯结构设计103.3.5型芯高度尺寸计算10第四章 塑件脱模结构的设计134.1脱模力计算134.2侧向分型与抽芯机构设计14第五章 浇注系统及温控系统设计175.1浇注系统的设计175.1.1主流道的设计175.1.2浇口的设计185.1.3塑料温控系统设计18第六章 模架的选择21总结与展望31致 谢32参考文献3327绪论第一章 绪 论1.1 模具工业在国民经济中的地位模具工业是国民经济的基础工业,是国际上公认的关键工业。模具生产技术水平的高低是衡量一个国家产品制造水平高低的重要标志,它在很大程度上决定着产品的质量,效益和新产品的开发能力。振兴和发展我国的模具工业,正日益受到人们的关注。早在1989年3月中国政府颁布的关于当前产业政策要点的决定中,将模具列为机械工业技术改造序列的第一位。模具制造的重要性主要体现在市场的需求上,仅以汽车,摩托车行业的模具市场为例。汽车,摩托车行业是模具最大的市场,在工业发达的国家,这一市场占整个模具市场一半左右。汽车工业是我国国民经济五大支柱产业之一,汽车工业重点是发展零部件,经济型轿车和重型汽车,汽车模具作为发展重点,已在汽车工业产业政策中得到了明确。汽车基本车型不断增加,2005年已达到170种。一个型号的汽车所需模具达几千副,价值上亿元。为了适应市场的需求,汽车将不断换型,汽车换型时约有80的模具需要更换。目前世界模具市场供不应求,模具的主要出口国是美国,日本,法国,瑞士等国家。中国模具出口数量极少,但中国模具钳工技术水平高,劳动成本低,只要配备一些先进的数控制模设备,提高模具加工质量,缩短生产周期,沟通外贸渠道,模具出口将会有很大发展。研究和发展模具技术,提高模具技术水平,对于促进国民经济的发展有着特别重要的意义。1.2 各种模具的分类和占有量1) 塑料模今年来,我国塑料模有很大的进步。在大型塑料模方面,已能生产34英寸大屏幕彩电塑壳模具,6kg大容量洗衣机全套塑料模具及汽车保险杆和整体仪表板等塑料模具。在精密塑料模具方面,已能生产多型腔小模数齿轮模具和600腔塑封模具,还能生产厚度仅为0.08mm的1模2腔的航空杯模具和难度较高的塑料门窗挤出模等。内热式或外热式热流道装置得以采用,少数单位采用了具有世界先进水平的高难度针阀式热流道模具,完全消除了制件的浇口痕迹。气体辅助注射技术已成功得到应用。在精度方面,塑料模具制造精度可达0.020.05mm(国外可达0.0050.01mm),分型面接触间隙为0.02mm,模板的弹性变形为0.05mm,型面的表面粗糙度值为Ra0.20.25g,塑料模具寿命已达100万次(国外可达300万次),模具制造周期仍比国外长24倍。这些标志着模具总体水平的参数指标与国外相比尚有较大差距。2) 模具CAD/CAE/CAM模具CAD/CAE/CAM技术是改造传统模具生产方式的关键技术,能显著缩短模具设计与制造周期,降低生产成本,提高生产质量。它使技术人员能借助于计算机对产品、模具结构、成形工艺、数控加工及成本等进行设计和优化。以生产家用电器的企业为代表,陆续引仅了相当数量的CAD/CAM系统,实现了CAD/CAM集成,并采用了CAE技术对成型过程进行计算机模拟等,数控加工的使用率也越来越高,取得了一定的经济效益,促进和推动了我国模具CAD/CAE/CAM技术的发展。近年来,我国自开发的有上海交大的冲裁模CAD/CAM系统;北京北航海尔软件有限公司的CAXA系列软件;吉林金网络模具工程研究中心的冲压CAD/CAE/CAM系统等,为进一步普及模具CAD/CAM技术创造了良好条件。目前我国计算机辅助技术软件开发,尚处于较低水平,需要知识和经验的积累。3) 模具标准件模具标准件对缩短模具制造周期,提高质量,降低成本,能起很大作用。因此,模具标准件越来越广泛地应得到采用。模具标准件主要有冷冲模架、塑料模架、推杆和弹簧等。新型弹性元件如氮气弹簧亦已在推广应用中。4) 模具材料与热处理模具材料的质量、性能、品种和供货是否及时,对模具的质量和使用寿命以及经济效益有着直接的重大影响。近年来,国内一些模具钢生产企业已相继建成和引进了一些先进工艺设备,使国内模具钢品种规格不合理状况有所改善,模具钢质量有较大程度的提高。但国产模具钢钢种不全,不成系列,多品种、精料化、制品化等方面尚待解决。另外,还需要研究适应玻璃、陶瓷、耐火砖和地砖等成型模具用材料系列。模具热处理使关系能否充分保证模具钢性能的关键环节。国内大部分企业在模具淬火时仍采用盐熔炉或电炉加热,由于模具热处理工艺执行不严,处理质量不高,而且不稳定,直接影响模具使用寿命和质量。近年来,真空热处理炉开始广泛用于模具制造。模具主要类型有:冲模,锻摸,塑料模,压铸模,粉末冶金模,玻璃模,橡胶模,陶瓷模等。除部分冲模以外的的上述各种模具都属于腔型模,因为他们一般都是依靠三维的模具形腔是材料成型。(1) 冲模:冲模是对金属板材进行冲压加工获得合格产品的工具。(2) 锻模:锻模是金属在热态或冷态下进行体积成型是所用模具的总称。按锻压设备不同,锻模分为锤用锻模,螺旋压力机锻模,热模锻压力锻模,平锻机用锻模,水压机用锻模,高速锤用锻模,摆动碾压机用锻模,辊锻机用锻模,楔横轧机用锻模等。按工艺用途不同,锻模可分为预锻模具,挤压模具,精锻模具,等温模具,超塑性模具等。(3) 塑料模:塑料模是塑料成型的工艺装备。塑料模约占模具总数的35,而且有继续上升的趋势。塑料模主要包括压塑模,挤塑模,注射模,此外还有挤出成型模,泡沫塑料的发泡成型模,低发泡注射成型模,吹塑模等。(4) 压铸模:压铸模是压力铸造工艺装备,压力铸造是使液态金属在高温和高速下充填铸型,在高压下成型和结晶的一种特殊制造方法。压铸模约占模具总数的6。(5) 粉末冶金模:粉末冶金模用于粉末成型,按成型工艺分类粉末冶金模有:压模,精整模,复压模,热压模,粉浆浇注模,松装烧结模等。1.3 中国模具发展现状(1) 模具CAD/CAE/CAM正向集成化、三维化、智能化和网络化发展1) 模具软件功能集成化。模具软件功能的集成化要求软件的功能模块比较齐全,同时个功能模块采用同一数据模型,以实现信息的综合管理与共享,从而支持模具设计,制造,装配,检验,测试及生产管理的全过程,达到实现最佳效益的目的。如英国Deleam公司的系列化软件就包括了曲面/实体几何造型,复杂形体工程制图,工业设计高级渲染,塑料模设计专家系统,逆向工程系统及复杂形体在线测量系统等。集成化程度高的软件还包括:Pro/E,UG和CATIA等。2) 模具设计,分析及制造的三维化。传统的二维模具结构设计已越来越不适应现代化生产和集成化技术要求。模具设计,分析,制造的三维化,无纸化要求新一代模具软件以立体的,直观的感觉来设计模具,所采用的三维数字化模型能方便地用于产品的CAE分析,模具可制造性评价和数控加工,成形过程模拟及信息的管理与共享。如Pro/E,UG和CATIA等软件具备参数化,基于特征,全相关等特点,从而使模具并行工程成为可能。另外,Cimatran公司的Moldexpert,Deleam公司的Ps-mold 及日立造船的Space-E/mold均是3D专业注射模设计软件,可进行交互式3D型腔,型芯设计,模架配置及典型结构设计。澳大利亚Moldflow公司的三维真实感流动模拟软件Moldflow Advisers已经受到用户广泛的好评和应用。面向制造,基于知识的智能化功能是衡量模具软件先进性和实用性的重要标志之一。如Cimatron公司的注射模专家软件能根据脱模方向自动产生分型线和分型面,生成与制品相对应的型芯和型腔,实现模架零件的全相关,自动产生材料明细表和供NC加工的钻孔表格,并能进行智能化加工参数设定,加工结果校验等。3) 模具软件应用的网络化趋势。随着模具在企业竞争,合作,生产和管理等方面的全球化,国际化,以及计算机软硬技术的迅速发展,模具软件应用的网络化的发展趋势是使CAD/CAE/CAM技术跨地区,跨企业,跨院所在整个行业中推广,实现技术资源的重新整合,使虚拟设计,敏捷制造技术成为可能。美国在其21世纪制造企业战略中指出,到2006年要实现汽车工业敏捷生产/虚拟工程方案,使汽车开发周期从40个月缩短到4个月。(2)模具检测和加工设备向精密、高效和多功能方向发展1) 模具向着精密,复杂,大型的方向发展,对检测设备的要求越来越高。目前国内厂家使用较多的有意大利,美国,日本等国的高精度三坐标测量机,并具有数字化扫描功能。实现了从测量实物-建立数学模型-输出工程图纸-模具制造全过程,成功实现了逆向工程的开发和应用。2) 数控电火花加工机床。日本沙迪克公司采用直线电机伺服器驱动的AQ325L,AQ550LIS-WEDM具有驱动反应快,传动及定位精度高,热变形小等优点。瑞士夏米尔公司的NCEDM具有P-E3自适应控制,PCE能量控制及自动编程专家系统,另外有些EDM还采用混粉加工工艺,微精加工脉冲电源及模糊控制(FC)等技术。3) 高速铣削机床(HSM)铣削加工是型腔模具加工的重要手段。而高速铣削具有工件温升低、切削力小、加工平稳、加工质量好、加工效率高(为普通铣削加工的5-10倍)及可加工硬材料(100mm,需要乘以0.850.9。在p49Mpa时, 因此S=0.2*207*0.9+17=54.26mm取侧壁厚度60mm就满足要求。B、矩形型腔底板厚度的确定因为p49Mpa, L1.5b查表可得S=0.08*156=12.48mm取底板厚度15mm就满足要求。3.3.4型芯结构设计主型芯采用局部嵌入固定。其特点是节约模具钢的便于加工。4.2型芯径向尺寸的计算 模具型芯径向尺寸是由制品的内径尺寸所决定的,与型腔径向尺寸的计算原理一样,分为两个部分来计算:dm=mm式中: dm型芯外径尺寸(mm) D1制品内径最小尺寸(mm)其余的符号含义同型腔计算公式零件内径长度最大尺寸d=197mm, =0.115d=(197+197*0.005+*0.115) = 198.060mm零件内径宽度最大尺寸d=147mm,=0.100mmd=(147+147*0.005+*0.100) =147.810mm3.3.5型芯高度尺寸计算模具型芯的高度尺寸是由制品的深度尺寸决定的,假设制品深度尺寸H1为最小尺寸,其公差为正偏差+,型芯高度尺寸为最大尺寸,其公差为负偏差-。根据有关的经验公式:hM=(mm) hM型芯高度尺寸(mm)H1制品深度最小尺寸(mm)其余公式中字母的含义同前面的含义深度最小尺寸H=48.5mm, =0.043h=(48.5+48.5*0.005+*0.043) =48.772mm塑件脱模结构的设计第四章 塑件脱模结构的设计由于改塑件脱模阻力不大,而顶杆加工简单、更换方便、脱模效果好,因此选用顶杆脱模机构。而中间的部分采用推管机构。推杆位置的设置采取了以下的原则:(1) 推杆设在脱模阻力大的地方(2) 推杆位置均匀分布(3) 推杆设在塑料制品强度刚度大的地方(4) 推杆直径应满足相应的刚度、强度条件,在满足条件的前提下,应尽量选用直径较大的推杆。本次设计的零件,所以推杆直径取得比较小,为了达到强度刚度要求设置了较多的推杆。4.1脱模力计算矩环形薄壁制品s/d 0.05 F (N)r型芯平均半径 (m)S制品壁厚 (m)E塑料弹性模量 (Mpa)Q塑料平均收缩率 (%)l制品对型芯的包容长度 (m)f制品与型芯静摩擦系数 f=0.10.2 脱模斜度 () 取1 m塑料的泊松比 m=0.380.42 k系数 k=2/(cos+2cos)k系数 k=1+fsincos1A盲孔制品型芯在脱模方向投影面积 (m)已知,、F=+0.1*0.029=6052N4.2侧向分型与抽芯机构设计本次设计有一个侧向型芯。所以使用外侧抽芯。(1) 斜导柱 斜导柱直径d与导柱孔应保持0.51mm的间隙。(2) 导柱的角度 本设计=18,楔紧块角度为20。(3) 抽心距的计算 通常抽心距等于侧芯深度加25mmS=13+4=17mm(4) 斜导柱工作部分长度L=S/sin18=56开模行程H=Sctg18=53(5) 抽拔力的计算F1=lhp(fcos-sin)式中 l活动侧芯被塑料包紧的断面周长(m);h成型芯部分的深度(m);p制品对侧心的压力,一般取812Mpa;f塑料对钢的摩擦系数,常用f=0.10.2;侧芯的脱模斜度,常取=12。已知l=132mm,h=13mm,p=10Mpa,f=0.2, =1F1=0.1320.01310106(0.2cos1-sin1)=3132N(6) 斜导柱所受弯曲力的计算P=/cosP弯曲力Q抽拔阻力(与抽拔力大小相等,方向相反)斜导柱的倾斜角P=3132/cos18=3293N(7) 斜导柱直径的计算d=式中 p最大弯曲力;l斜导柱有效工作长度;弯弯曲许用应力,对碳钢可取137Mpad=23.79mm取标准斜导柱的公称直径为25。浇注系统及温控系统设计第五章 浇注系统及温控系统设计5.1浇注系统的设计浇注系统是指模具中从注射机喷嘴开始到型腔为止的塑料流动通道。浇注系统设计好坏对制品性能,外观和成型难易程度影响颇大。根据注塑件的要求及模具的结构等方面来考虑选择浇注系统。设计原则(1)能顺利地引导熔融塑料充满型腔,不产生涡流,又有利于型腔内气体的排出。(2)在保证成型和排气良好的前提下,选取短流程,少弯折,以减小压力损失,缩短填充时间。(3)尽量避免熔融塑料正面冲击直径较小的型芯和金属嵌件,防止型芯位移或变形。(4)浇口料容易清除,整修方便,无损制品的外观和使用。(5)浇注系统流程较长或需要开设两面个以上浇口时,由于浇注系统的不均匀收缩导致制品变形,应设法防止。(6)在一模多腔时,应使各腔同步连续充浇,以保证各个制品一致性。(7)合理设置冷料井、溢料槽,使冷料不得直接进入弄腔及减小毛边的负作用。(8)在保证制品质量良好的条件下,浇注系统的断面和长度应尽量取小值,以减小对塑料的占用量,从而减小回收料。5.1.1主流道的设计断面形式:截面形状采取圆形,这种形状热量损失小,流动阻力小,效果最佳,但加工较难。注射机的喷嘴头部与主流道衬套的凹下的球面半径R相接触,二者必须匹配,无漏料。一般要求主衬套球面半径R比喷嘴球面半径大12mm,主流道进口直径d比注射机喷嘴出口直径d应大0.51mm.其作用:一是补偿喷嘴与浇注道的对口误差;二是使喷嘴与主衬套球面配合良好。为了便于凝料从主流道中拔出,主流道设计成圆锥形,其半锥角a=24,表面粗糙度应有Ra=0.8以上。主流道出口应做成圆角,圆角半径r=0.30.5mm或r=d/8.为减少压力损失,主流道长度尽可能短些,常取L60mm。喷嘴球面半径为10mm (见上注射机技术参数)主衬套球面半径R取12mm主流道进口直径d取4.5mm主流道出口直径d取6mm半锥角a=3主流道长度L取45mm5.1.2浇口的设计取用直接浇口,直接浇口是直接和主流道连接,由主流道直接进料。它可以做成顶浇口和中心浇口。由于浇口尺寸大,熔体压力损失小,流动阻力小,进料快,容易成型,适用于任何塑料,常用于成型单腔模,大而深的壳型制品。因为流程短,压力传递好。熔体从上端流向分型面(低端),故有利于排气和消除接痕。直接浇口进、出口端直径d、d可以由主浇道的尺寸决定。5.1.3塑料温控系统设计在注射工艺过程中,模具的温度直接影响着制品质量和注射周期,各种塑料的性能、成型工艺要求的不同相应的模具对温度的要求也不同,PS在注射成型进所需要的模具温度为4060,对于任何塑料制品,模具的温度的波动较大都是不利的,过高的模具温度会使塑料制品在冷却脱模后发生变形,延长冷却时间降低生产率,为了避免这种现象的发生,就必须采取模具温度调节系统。塑料传给模具的热量:Q=n m C (T1-T2)式中: Q单位时间内塑料传给模具的热量KJ/h;n每小注射的次数;m每次注射的塑料量,包括浇江系统(kg);C塑料的比热容(J/kg);T1熔融塑料进入模腔的温度();T2制品脱模温度();选定注射机每小时注射的次数为50,则根据以上公式:PS的C=1340(J/ kg);已知m=0.16, T1=180, T2=60,选定注射机的每小时注射的次数为50,则根据以上的公式,得Q=500.161340(180-60)=1.30106 (KJ/h)冷却时所需要的冷却水量式中: M1通过模具的冷却水的质量(kg);T3出水温度();T4进水温度();导热系数(J/m);由由4表8-26,查得=452(J/m)所以有冷却水的质量:M1=kg根据冷却水处于湍流状态下的流速v与水管道直径d的关系,确定模具冷却水道直径d:d=式中:M1冷却水的质量(Kg);v管道内冷却水的流速,一般取0.82.5m/s;水的密度(Kg/m3)。根据以上公式:取冷却水管道的直径为14mm.冷却管道总传热面积计算公式:式中:R冷却管道壁与冷却介质间的传热系数(J/m2)(J/m2)f与冷却介质有关的物理系数,查表8-294得,f=7.98T模具温度与冷却介质之间的平均温度;其余符号意义同上其中T=(60+40)/2=50冷却管道的孔数:n=式中A冷却装置总的传热面积(m2); d冷却水管管道直径(m); L冷却管道的长度(m)。则 所以,冷却水道的孔数在动、定模板之中各取一个就可以达到冷却的要求。由于PS是要求模温较低的塑料,不断注入的熔融塑料使模温能够达到PS注射成型所需的模温,所以不必考虑需要加热提升温度。模架的选择第六章 模架的选择本次设计选用的标准模架型号是:A50050042Z GB/T12556.190A品种(基本型号)500500系列(模板周边尺寸)42规格(基本组合编号)Z导柱的安装方式定模板厚度:A=80mm动模板厚度B=63mm垫块厚度:C=125mm模具厚度:H模=400mm模具外形尺寸:750x630x400mm总结与展望总结与展望通过这次毕业设计,综合运用本专业所学课程的理论和生产实际知识,进行一次注塑模具设计工作的实际训练,从而培养和提高了学生的独立工作能力,巩固与扩充了模具制造等课程所学的内容,体现出自己单独设计模具、综合运用知识的能力,是真正的学以致用,突出自己劳动成果的喜悦心情,从中也发现自己平时学习工作中的不足和薄弱环节、从而加以弥补。随着模具技术的发展,模具已成为现代化不可缺少的工艺装备,模具设计是承学校机械专业最重要的教学环节,它是我们对所学知识的综合运用,从而使学生对模具设计制造的过程有了基本的了解,为以后的工作及进一步学习深造打下了坚实的基础。在这次设计过程中,掌握了注塑模具设计的方法与步骤及制造。如计算、绘图、查阅设计资料和手册、熟悉标准和规范,提高了自身的设计能力,认识自了我,使所学的知识在实际中的应用,对模具产品设计开发有一定的了解,在大脑里形成一个比较系统化的概念。通过这次实践,培养了我们的实际动手能力,将我们所学的课程与实际生产有机地结合起来,巩固所学的专业知识,从而真正掌握计算机辅助模具设计制造的技能。突出了自己的长处,也发现了自己的不足,从而完善自己的知识面,使自己做得更好!致谢致 谢本次毕业设计是对我大专三年所学知识的一次全面考验,它也是对即将走向社会的我们进行的一次有效的训练。在为期几个月的毕业设计过程中,我深深地感觉到基础知识的重要, 在设计中使自己进一步熟悉了Auto CAD等绘图软件的应用,但是对于某些方面还是运用不够灵活。在模具设计的过程中,参考模具设计手册,自己设计出了较为合理的模具,但在一些细节问题的处理上仍考虑得不够全面,对于一些复杂的曲面的模具的设计还是需要继续学习。通过这次毕业设计,让我学到很多以前没有学到的东西,同时也让我明白了很多道理。无论以后遇到什么样的困难,都要学会怎样去面对,怎样去克服,怎样去解决。在此我非常感谢我们的卢老师,在这次毕业设计过程中她帮助我解决了很专业方面的问题,以及在模具的设计方面他们也给予我很大的帮助。参考文献参考文献(1) 黄成.UGNX6.0模具设计技术教程M.国防工业出版社,2008(2) 张克涛.模具设计典型范例M.化学工业出版社,2008(3) 李波.UGNX5.0注塑模具设计完全自学手册M.清华大学出版社,2007(4) 黄毅宏.模具制造工艺M.机械出版社1999(5) 奚永生.精密注塑模具设计M.中国轻工业出版社,2000(塑料模具的编制和使用M. B.鲍里索夫 华联666.5:666.3.032石膏模具被广泛用于铸造陶瓷行业所需的用具。除了具有一定的优势,由于它们工作表面下穿在体内的水分和电解质的行动,所以还具有机械强度低,工作寿命短的好处。除此之外,在烘干机的温度不能高于65度,高于此温度石膏将被销毁。陶瓷产业开始安装时,寻找替代石膏的必要性增加为半自动成型和干燥加剧干燥条件机。我们的工厂1967年开始搜索替代石膏,并为此组织了一个研究小组,其中包含以下工人:AV Saveleva,PS波利亚科夫,电讯管理局局长Pashkova,弗吉尼亚州Kholkin,AV SarichevF. I. Lisov,和其他人。该研究小组在国家陶瓷研究的数据指导研究所开始工作。但是,这并没有回答一些工厂工作所产生的问题,例如:如何按模具设计和制造,以避免打击在两个平面的交点开裂面,一批每单位体积的模具,安排用什么热处理,如何获得均匀分布的孔隙,一般增加孔隙度,以及如何避免被人体坚持等。他们的研究结果之后,本集团于1969年开始准备开发PVC模具,并转换其使用的工厂的生产线。目前的时间有五板生产线,其中三个是在工厂浅200毫米板和两个深200毫米板,以及七行杯。使用塑料生产模具的24000板和35-37,000杯每一天(24小时)。临时的,每年可节省从所得只有一条生产线的引进,为2500卢布。世界杯生产的塑料模具的工作寿命达到4000个周期,仍然可以增加。板生产模具的生活仍然没有得到确定。他们的工厂于1969年举办了一个准备模具部分(图一)。原料是国内的聚氯乙烯乳胶,L - 5级,或乳化聚氯乙烯,E级62。聚氯乙烯是氯乙烯聚合的产物。(图一)(图二)它是一个白色的细分散(没有残留于0056筛号)粉末,密度1.41克/厘米3。在温度聚氯乙烯颗粒170-180和轻微的压力下(具体压力0.05公斤/厘米2)融化和凝聚。在第一阶段编制的模具是一个初步的振动成型(上振动表)确保统一的孔隙度。 振动表执行50振荡幅度0.5/秒。 振动成型是开展为15-20秒。初步振动成型是模具的过程中必不可少的一部分,因为,在成型过程中,产生内部应力集中分子接触点附近细颗粒的凝聚力。在烧结过程中,这种内部的压力是特别危险的。它可以被删除振动,这几乎完全打破了粒子之间的所有连接,并确保其均匀分布。在这块编制的塑料模具的基本设备是金属冲压模具(图二)这是45级或圣3钢。其内部表面必须镀铬。图一、手压;2)SNOL电加热模具热处理柜;3)内阁冷却模具;4)表的组装和拆除;5)站在准备模具;6)存储站在塑料;7)电加热干燥柜;8)完成的模具;9)表塑料包装;10)为测量出塑料表;11)振动表。图二、按模。 A)组装;B)拆除。如图扁平制品(板)塑料模具填补按模的过程(图三)。L-5粉末,以前在ll0在干燥柜干燥,然后筛选通过第05号筛,收费是按模矩阵,并用专用工具夷为平地。 胶量取决于模具的类型(卷)。为浅200毫米板,它是600克,深200毫米板660克,碗碟400克,并为杯500-515克。按模具打孔,然后插入在这样一种方式,它根据其自身的重量进入,直到它与塑料接触矩阵。要检查装配在这一点上的正确性,冲床旋转矩阵。组装冲压模具放在震动表压缩为15-20秒。压缩之后,矩阵法兰和打孔法兰之间的差距应该是8-10。顶部,从而给了0.05公斤/厘米2的压力。监测温度,温度计插入因此,它触及冲床中心。一个少量的塑料堆打孔法兰,其颜色的变化,是用来评估模具的准备。加热过程持续2-3小时,在其完成的按模的温度是170-175度。热过程完成后,温度计被删除并采取按模内阁,并放置到通风降温的内阁。按模,然后拆除使用一个提取螺丝。准备的塑料模具被删除,修剪边缘光滑,经检查后已准备就绪。中空制品(杯)模具准备根据以下的时间表。正确的聚氯乙烯塑料的金额投入矩阵(图四),并稳定下来。两个22-24毫米厚的间隔被放置在法兰矩阵1,矩阵2降低到使法兰盘上休息的间隔。然后放进冲3环,使法兰与水平法兰盘。组装冲压模具,然后上交上震动表法兰下降,与打孔法兰站在一个50 50毫米块。然后垫片。从法兰盘上取下,矩阵的底部放置8-10公斤的重量,定位,其中心轴冲压模具。振动器是打开背后的法兰环塑料振捣15-20秒。在振动矩阵和冲压法兰之间的间隙应约5-7打孔法兰和环约在10毫米之间。按模具,然后上交,和5-6毫米打孔法兰奠定了厚厚的包装,然后重量放在这给压力的0.05公斤/厘米2的热处理过程。按模具的重量,放在一个粘土基地6-8厘米,在电干燥柜厚根据的1.5-2 h(图5)的温度加热过程进行了180-185水银温度计监测温度。在热处理结束负载被删除,记者将电柜压在手上按直到环和冲压模法兰矩阵法兰接触。 10分钟后保留下的新闻按模拆除,放置在通风内阁降温至40-45按模被拆除和准备的塑料模具中提取,修整后投入使用。(图3) (图4)(图5)图3、1)停止垫圈;2)环;3)冲床;4)模具;5)聚氯乙烯。图4、 1)矩阵;2)环;3)冲床;4)螺钉;5)模具。图5、加工塑料模具的热处理图。直径为200毫米的钢板。在这些聚氯乙烯模具的准备和他们在工厂使用的经验表明,从上述的准备计划的偏差,导致各种故障在外观这表明,在与他们形成制品的过程中的模具显示下按,材料的孔隙率空心模具的肩膀上,下环上的空心模具的干裂缝。恒定控制调温的干燥柜内阁确保一个统一的期间的冲压件的热处理室的温度,并确保均匀加热对于所有的塑料厚度。由此产生的烧结均匀,防止模具生产与塑料之间的边缘和中心热膨胀系数不同。这大大降低模具的工作表面在使用过程中发生裂缝,并增加其工作生活。积累使用的模具工厂经验已经表明,它是必要的支付注意:半自动机底座下的模具持有人仔细调整;选择成型的时间表;避免与身体接触的时刻的辊突然降低;选择正确的成型辊的速度(300-550 转杯和板250-275转)和模具持有人(750-800 转杯和板300-500转)为了避免生产废“嗡嗡声”和“呼呼声”。如果不遵守这些要求,也可导致模具的损坏(崩过肩,并挖掘出与中空制品的底部)。生产的模具,不同的颜色从玫瑰到深褐色,根据工期在不断的压力和电柜最后温度的热处理。深褐色的具有低孔隙度,并在实践中不能使用。彩色的上升有足够的工作性质,但其机械强度低,大大降低了他们的工作生活。获得均匀分布的毛孔孔隙率31-35的正常工作,并在同一同时保留必要的机械强度,在生产中最棘手的问题之一是模具。如果被迫热处理,这迅速导致表面地壳的外观原料在模具内部。为了加快热量,如果最终温度升高高于210治疗,这导致了塑料的分解与摧毁了表面的气体演变模具。经广泛调查后,按模塑料的最佳加热时间表,这给模具所需的质量,如图五。在编制和使用的模具,塑料的正确金额的经验,每单位体积模具被确定为0.9克/厘米3。这使其他因素保持不变,保持为不断密度模具。模具验收的技术标准,建立了工厂。他们必须有一个顺利密集的工作表面和均匀的色彩匹配既定的标准。尺寸变化不得超过正负0.05。模具必须有没有变形。他们的孔隙率必须在31-35之间。其吸水率决定在工厂开发出一种方法。在这些模具制品的表面要求没有进一步的治疗,这是一个商业优势。石膏的工厂消费减少了每年500万吨。劳动力需求重型装载/卸载工作是减少,劳动者的工作/模塑解除,交通是释放。厂队将继续引进更进步的方法准备工作加快增加输出给每按模模具的热处理工艺,塑料模具,并要提高其机械强度,同时保持高孔隙度。参考文献1、SM. Tsenter et al,Steklo i Keram,第1号(1969年)。4THE PREPARATION AND USE OF PLASTIC MOLDS M. B. Borisov UDC 666.5:666.3.032 Plaster molds are widely used for casting wares in the ceramics industry. Apart from certain ad- vantages, they have a low mechanical strength and short working life due to wear of the work surface under the action of water and electrolytes in the body. Besides this, the temperature in the dryer cannot be higher than 65 as above this temperature the plaster is destroyed. The necessity of finding a substitute for plaster was increased when the porcelain industry began in- stalling semiautomatic machines for molding and drying, with intensified drying conditions. The search for a substitute for plaster began in our factory in 1967, and to this end a group was organized containing the following workers: A. V. Saveleva, P. S. Polyakov, T. A. Pashkova, V. A. Kholkin, A. V. Sarichev, F. I. Lisov, and others. At the start of their work the research group were guided by data from the State Ceramics Research Institute 1. However, this did not answer a number of questions arising from the working of the plant, such as: how to design and make press molds so as to avoid cracking in the plane of intersection of two surfaces, what batch to take per unit volume of mold, what schedule to use for the heat treatment, how to obtain uniform distribution of pores and increase general porosity, and how to avoid adhering by the body, etc. Following on the results of their research, in 1969 the group began developing the preparation of PVC molds, and converting the production line of the factory to their use. At the present time there are in the factory five production lines for plates, three of which are for shallow 200 mm plates and two for deep 200 mm plates, as well as seven lines for cups. Using the plastic molds a totalof24,000 plates and 35-37,000 cups are produced per day (24 h). The provisional annual saving accruing from the introduction of only one production line is 2500 rubles. The working life of the plastic molds in cup production reaches 4000 cycles and can still be increased. The life of the molds in plate production has still not been determined. A section for preparing the molds was organized in the factory in 1969 (Fig. 1). The raw material was domestic polyvinylchloride latex, grade L-5, or emulsified polyvinylchloride, grade E-62. Polyvinyl- chloride is the product of polymerization of vinyl chloride. It is a white finely dispersed (no residue on No. 0056 sieve) powder of density 1.41 g/cm 3. At a tempera- ture of 170-180 and under slight pressure (specific pressure 0.05 kg/cm 2) the polyvinylchloride par- ticles melt and cohere. The first stage in the preparation of the molds is a preliminary vibromolding (on the vibrotable) which ensures uniform porosity. The vibrotable performs 50 oscillations/sec with an amplitude of 0.5 ram. The vibromolding is carried out for 15-20 sec. This preliminary vibromolding is an essential part of the process for making the molds, since, during molding, internal stresses are generated which are concentrated near the points of contact of molec- ular cohesion of the fine particles. This internal stress is especially dangerous during the process of sin- tering. It can be removed by vibration, which almost completely breaks all connections between particles and ensures their uniform distribution. The basic piece of equipment in the preparation of the plastic molds is the metal press-mold (Fig. 2) which is made from grade 45 or St. 3 steel. Its internal surface must be chromium plated. Dulevo Porcelain Factory. Translated from Steklo i Keramika, No. 3, pp. 7-9, March, 1972. ?9 1972 Consultants Bureau, a division of Plenum Publishing Corporation, 227 g/est 17th Street, New York, N. Y. 10011. All rights reserved. This article cannot be reproduced for any purpose whatsoever without permission of the publisher. A copy of this article is available from the publisher for $i5.00. 147 ,.- 13 500 l 2 3 45 6 fi IO 9 8 7 Fig. I Fig. 2 Fig. I. i) Hand press; 2) SNOL electrically heated cabinet for heat treatment of the molds; 3) cabinet for cooling the molds; 4) table for assembly and dismantling; 5) stand for prepared molds; 6) storage for the plastics; 7) electrically heated cabinet for drying; 8) stand for finishing the molds; 9) table for packing plastics; i0) table for measuring out plastics; ii) vibrating table. Fig. 2. Press-mold. a) Assembled; b) dismantled. The process of filling the press-mold for making flat ware (plates) plastic molds is shown in Fig. 3. L-5 powder, which has previously been dried in the eleetrodrying cabinet at ll0 and then screened through a No. 05 sieve, is charged into the matrix of the press-mold and leveled with a special tool. The amount of plastic depends on the type (volume) of the mold. For shallow 200 mm plates it is 600 g, for deep 200 mm plates 660 g, for saucers 400 g, and for cups 500-515 g. The press-mold punch is then in- serted into the matrix in such a way that it enters under its own weight until it is in contact with the plastic. To check the correctness of assembly at this point, the punch is rotated relative to the matrix. The assembled press-mold is placed on the vibrotable and compacted for 15-20 sec. After com- pacting, the gap between the matrix flange and the punch flange should be 8-10 ram. The press-mold is next inserted into SNOL electrocabinet for the heat process and a weight is placed on the top so as to give a pressure of 0.05 kg/cm 2. To monitor the temperature, a thermometer is inserted so that it touches the center of the punch. A small amount of the plastic is heaped on the punch flange, and its change in color is used to assess the readiness of the mold. The heat process continues for 2-3 h and at its completion the temperature of the press-mold is 170-175 After the completion of the heat process, the thermometer is removed and the press-mold taken from the cabinet and placed into the ventilated cabinet to cool. The press-mold is then dismantled using an ex- traction screw. The prepared plastic mold is removed, trimmed smooth at the edges, and after inspection is ready for use. The molds for the hollow wares (cups) were prepared according to the following schedule. The cor- rect amount of PVC plastic was put into the matrix Fig. 4) and leveled off. Two 22-24 mm thick spacers were placed on the flange of the matrix 1, and the matrix 2 lowered onto it so that the ring flange was resting on the spacers. The punch 3 was then lowered into the ring so that its flange was level with the ring flange. The assembled press-mold was then turned over and placed flange down on the vibrotable, with the punch flange standing on a 50 x 50 mm block. The spacers were then. removed from under the ring flange, and a weight of 8-10 kg placed on the bottom of the matrix, positioned to that its center lay on the axis of the press-mold. The vibrator was turned on and the ring held behind the flange vibrated the plastic for 15-20 sec. After vibrating the clearance between the flanges of the matrix and punch should be about 5-7 ram, and between the punch flange and the ring about 10 mm. The press-mold was then turned over, and 5-6 mm thick packing laid on the punch flange, and then the weight placed on this which gave the pressure of 0.05 kg/cm 2 for the heat process. The press-mold, with the weight, was placed in the electrodrying cabinet on a fireclay base 6-8 cm thick. The heating process was carried out according to the graph (Fig. 5) for 1.5-2 h up to a temperature of of 180-185 The temperature was monitored by a mercury thermometer. At the end of the heat treatment the load was removed and the press-mold taken from the electrocabinet and pressed on the hand press until 148 Fig. 3 tc 160 _ . =.: .iu/ 0 20 40 60 80 lOO Time, rain Fig. 4 Fig. 5 Fig. 3. 1) Stop washer; 2) ring; 3) punch; 4) die; 5) polyvinylchloride. Fig. 4. 1) Matrix; 2) ring; 3) punch; 4) screw; 5) mold. Fig. 5. Heat treatment graphs for processing plastic molds. 200 mm diameter plates. 1) For cups; 2) for shallow the ring and punch flanges made contact with the matrix flange. After retaining under the press for 10 min the press-mold was removed and placed in the ventilated cabinet to cool down to 40-45 The press-mold was dismantled and the prepared plastic mold extracted. After trimming it was ready for use. Experience in the preparation of these polyvinylchloride molds and in their use in the factory has shown that deviation from the above preparation schedules leads to the appearance of various faults in the molds which show up during the process of forming wares with them: underpressing, porosity of the ma- terial under the shoulders of the hollow mold, ring cracks on the stem of the hollow mold. Constant control of the electrodrying cabinet by means of the thermoregulator ensures a uniform temperature in the chamber during the heat treatment of the pressings, and ensures uniform heating of the plastic for all section thicknesses. The resultant uniformity of sintering prevents the production of a mold with different coefficients of thermal expansion between the edges and center of the plastic. This greatly reduces the occurrence of cracks in the working surface of the mold during use and increases its working life. Accumulated experience in the use of the molds in the factory has shown that it is necessary to pay attention to: careful adjustment of the mold holder under the pedestal of the semiautomatic machine; selec- tion of the molding schedule; avoiding sudden lowering of the roller at the moment of contact with the body; the selection of the correct speed for the molding roller (500-550 rpm for cups and 250-275 rpm for plates) and for the mold holder (750-800 rpm for cups and 300-500 for plates) in order to avoid the production of scrap in the form of humpers and whirlers. Failure to observe these requirements can also lead to damage to the mold (chipping off the shoulder, and digging out the bottom with hollow ware). The molds when produced vary in color from rose to dark brown, according to the duration of the heat treatment at constant pressure and the final temperature in the electrocabinet. The dark brown ones have low porosity, and in practice cannot be used. The rose colored ones have adequate working proper- ties, but their low mechanical strength significantly reduces their working life. Obtaining the normal working porosity of 31-35%, with uniformly distributed pores, and at the same time retaining the necessary mechanical strength, was one of the most difficult problems in the production of the molds. If the heat treatment was forced, this rapidly led to the appearance of a surface crust with a raw interior in the mold. If the final temperature was raised above 210 in order to speed up the heat treatment, this led to decomposition of the plastic with the evolution of gases which destroyed the surface of the mold. After extensive investigation, the optimum heating schedule for the plastic in the press-mold, which gave molds of the desired quality, was found and is shown in Fig. 5. From experience in the preparation and use of the molds, the correct amount of plastic per unit vol- ume of mold was established as 0.9 g/cm 3. This enables, with other factors remaining constant, to main- tain a constant density for the molds. The technical criteria for acceptance of the molds were established in the factory. They must have a smooth dense working surface and a homogeneous color matching the established standard. Dimensional 149 variations must not exceed =0.05%. The molds must have no deformations. Their porosity must fall within the limits 31-35%. Their rate of water absorption is determined by a method developed in the factory. The surface of wares made in these molds requires no further treatment, which is a commercial advantage. The consumption of gypsum by the factory is reduced by 500 tons per year. The labor re- quirement on heavy loading/unloading work is reduced, the work of the laborer/molders is relieved, and transport is released. The factory team continue to work on the introduction of more progressive methods of preparing plastic molds, on speeding the heat treatment process to give increased output of molds per press-mold, and on increasing their mechanical strength whilst preserving a high porosity. 1. LITERATURE CITED S. M. Tsenter et al., Steklo i Keram., No. 1 (1969). 150
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