基于plc搅拌机控制系统的设计

本科生毕业设计（论文）第I页基于PLC搅拌机控制系统的设计摘要随着我国十二五规划的进一步推进，国家对各项基础设施投资力度的进一步加大，市场对优质刨花板的需求将进一步提高。为此，如何提供优质、廉价、性能可靠、节能环保、维护方便的刨花板生产设备，已成了设备厂商急需解决的问题。本文应用了西门子S7-300系列PLC完成该系统刨花拌胶、搅拌控制。搅拌机控制系统的刨花由螺旋给料机供给，压力传感器检测刨花量。胶由胶泵抽给，电磁流量计检测胶流量；刨花和胶按一定的比例送到搅拌机内搅拌，然后将混合料供给下一道工序蒸压成型。要求刨花量和胶流量恒定，并有一定的比例关系。双轴搅拌机采用双轴对向搅拌，搅拌机的喷胶器使胶呈雾状喷射到刨花中。该系统配备的混胶器可以使固化剂与胶在其中混合，而不是把固化剂加到调胶罐中。本系统具有搅拌均匀、施胶量低等功能。调胶系统采用PLC集中控制，PLC根据各部传感器得到刨花的重量、含水率，来调整施胶量的固体含量。使施胶后的刨花含水率控制在理想的状态上。这样的优点是在生产线临时停机时，可以避免胶的浪费。因此，为企业及国家节省了大量的资金和生产原料。关键词：PLC；PID；S7-300；变频器TheDesignOftheMixerControlSystemBasedonPLCABSTRACT本科生毕业设计（论文）第II页Asthe12thfive-yearplanisfurtheron,thestategoesonincreasingtheinfrastructureinvestment,andthemarketwillneedthemorehigh-classparticleboard.Sohowtoprovidecheap,reliableperformance,energysavingandeasymaintenanceparticleboardproductionequipmentneedstoberesolved.SiemensPLCapplicationseriess7-300seriesistocompletethesystemcontrol.PC.Mixercontrolsystembytwo-stagespiralfeedersuppliespressuresensordetectionprocesses,quantity.Bygluepumpstoglue,gluewithelectromagneticflowmetertestflow;Particleandgluetoatacertainratetostirthemixer,andthenwillmixingsupplyaprocessunderautoclavetoshape.Paringquantityandplasticflow,andacertainconstantrelationshipofscale.Dualaxlemixerusedformixing,blendertofurtherthesprayadhesiveglueisanhazysprayintotheparticle.Therubbermixingsystemequippedwiththemachinecanmakecuringagentandtherubberinthemixof,ratherthanthecuringagentaddedtothegluetank.Thissystemhasastirwell,gluelowquantityfunction.AdjustablegluesystemUSESPLCcentralizedcontrol,PLCaccordingtogettheweightofeachsensorpre-press,moisturecontent,toadjusttheamountofgluesolidcontent.Makeglueofmoisturecontentinpre-pressaftercontrolidealstate.Suchadvantagesinproductionlineistemporary,canavoidgluewhenstopwaste.Therefore,theenterpriseandgovernmenttosavealotofmoneyanrawmaterial.keywords：PLC；PID；S7-300；FrequencyConverter本科生毕业设计（论文）第III页目录摘要..........................................................IABSTRACT.......................................................I目录........................................................III1绪论.........................................................12搅拌机控制系统的技术概述.....................................42.1PLC技术概述.................................................................................................42.1.1可编程控制器...........................................................................................................42.1.2PLC的结构.............................................................................................................52.1.3PLC的特点..............................................................................................................62.1.4PLC的基本功能.....................................................................................................72.1.5PLC软件系统..........................................................................................................82.1.6PLC的发展趋势.....................................................................................................92.2变频器简介................................................................................................92.3西门子S7-300软件概述...........................................................................92.3.1西门子S7-300系列PLC的一般特性..................................................................92.3.2西门子S7-300系列PLC的基本硬件组成........................................................112.3.3STEP7-V5.4(西门子S7-300编程软件)..........................................................1443搅拌机控制系统的设计方案...................................153.1控制系统的工艺过程及控制要求...........................................................153.2系统的控制方案.......................................................................................173.3基于PLC的拌胶机控制系统的特点.....................................................193.3.1施胶机具有如下主要特点....................................................................193.3.2拌胶机对比传统拌胶系统特点............................................................194搅拌机硬件系统设计..........................................204.1PLC的选型...............................................................................................204.2控制系统的仪表选用...............................................................................20本科生毕业设计（论文）第IV页5搅拌控制系统软件设计.......................................225.1可编程控制器在模拟量闭环控制中的应用...........................................225.1.1PID控制器的数字化..............................................................................................235.1.2回路输入输出变量的转化与标准化.....................................................................255.2搅拌机系统程序流程图...........................................................................22总结........................................................27致谢........................................................28参考文献......................................................30附录:程序.....................................................31本科生毕业设计第1页1绪论刨花板又叫微粒板、蔗渣板，由木材或其他木质纤维素材料制成的碎料，施加胶粘剂后在热力和压力作用下胶合成的人造板。又称碎料板。主要用于家具和建筑工业及火车、汽车车厢制造。刨花板是将木材加工剩余物、小径木、木屑等物切削成一定规格的碎片，经过干燥，拌以胶料，硬化剂、防水剂等，在一定的温度、压力