DISTRIBUTED CONTROL SYSTEM BASED ON CC-LINK
FIELDBUS IN THE BOPP FILM PRODUCT LINE
LI Zhong1,2, LI Yan2, YU Meng-hong2, CHEN Hong-wei2 , HE Zu-jun2
(Dept. of Electronics and Information, East China Shipbuilding Institute, Zhenjiang 212003 China)
Abstract The paper introduces a distributed control system based on CC-Link fieldbus in the BOPP film product line. Mitsubishi Q02CPU PLC is used in the system and 590 series controller is used as its DC driver. Several measured signals are transmitted to PLC via CC-Link and distributed I/O modules such as AJ65SBTB1-16D, FX2N-32CCL, etc. In this paper the process of BOPP film production and the characteristic of CC-Link are introduced. Because the product line is continued working, its devices are spread around 80 meters, and its controlled process is complex. For above reasons, the distributed control system is consisted of 4 subsystems with relative independent function. Viz. the speed chain drive control system, the temperature control system, the film thick measured system and the auxiliary control system. The actual application shows that the distributed control system is simple, reliable and good real-time. There is a powerful demonstration for the its further application.
KEY WORDS fieldbus; CC-Link; distributed control; BOPP; PLC; IPC; single-chip microcomputer
摘要 本文介绍了一种BOPP薄膜生产线的CC-Link现场总线集散控制系统,系统采用三菱Q02CPU PLC,直流传动采用590系列直流调速器,多种检测信号通过分布式I/O组件AJ65SBTB1-16D、FX2N-32CCL等,经由 CC-Link传送至PLC。文中简要介绍了BOPP薄膜生产过程及CC-Link结构特点,由于该生产线连续作业,设备分布较分散约80米,控制过程较为复杂,因此整个集散控制系统在功能上由4个相对独立的子系统组成,即速度链传动控制系统、温控系统、测厚系统及辅助控制系统。实际应用表明该系统简洁、可靠,实时性强,为今后进一步的应用提供了有力实证。
关键词 现场总线;CC-Link;集散控制;BOPP;PLC;工控机;单片机
中图分类号 TP273,TP391 文献标识码:A
1 引言
BOPP是Biaxial Oriented PolyPropylene (双向拉伸聚丙烯)的缩写,BOPP薄膜具有拉伸强度大,透明度高,保鲜性好、光泽明亮、彩印鲜艳、外观装饰华贵等优点,而且还具有很高的机械强度和附着力以及极好的化学性和良好的化学稳定性(与名种酸、碱、盐不发生化学反应),耐水耐热,是一种高级塑料包装材料,广泛应用于香烟、服装、食品、印刷品等、也可做粘胶带基及电容器的电介质。
BOPP薄膜生产线工作原理是:根据薄膜生产工艺要求,将挤出机及机头的各节筒体分别加热到不同的工作点,按配方通过料斗不断地注入料粒;熔融状的物料由机头挤出后,经过冷却辊冷却,形成窄而厚的薄膜厚片;薄膜厚片经过储片架整理后,被送入纵向拉伸区,根据工艺要求由慢速辊和快速辊进行2.5~5.0倍的纵向拉伸处理;横向拉伸区用于实现薄膜的第二次拉伸,即横向拉伸,该区域涉及薄膜的横拉分区加热控制、同步传动控制、破膜检测及其处理等问题,是实现有效成膜的关键之一;薄膜经过双向拉伸(即纵拉和横拉)后,被送入后处理区域进行后续工艺的处理,再经过上卷辊整理,由两台收卷辊轮换进行恒张力收卷,最终形成成品膜。