基于plc搅拌机控制系统的设计.doc

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Control System Based on PLC ABSTRACT As the 12th five-year plan is further on, the state goes on increasing the infrastructure investment ,and the market will need the more high-class particleboard . So how to provide cheap ,reliable performance, energy saving and easy maintenance particleboard production equipment needs to be resolved . Siemens PLC application series s7-300 series is to complete the system control. PC. Mixer control system by two-stage spiral feeder supplies pressure sensor detection processes, quantity. By glue pumps to glue, glue with electromagnetic flowmeter test flow; Particle and glue to at a certain rate to stir the mixer, and then will mixing supply a process under autoclave to shape. Paring quantity and plastic flow, and a certain constant relationship of scale. Dual axle mixer used for mixing, blender to further the spray adhesive glue is an hazy spray into the particle. The rubber mixing system equipped with the machine can make curing agent and the rubber in the mix of, rather than the curing agent added to the glue tank. This system has a stir well, glue low quantity function. Adjustable glue system USES PLC centralized control, PLC according to get the weight of each sensor pre-press, moisture content, to adjust the amount of glue solid content. Make glue of moisture content in pre-press after control ideal state. Such advantages in production line is temporary, can avoid glue when stop waste. Therefore, the enterprise and government to save a l