PLC与变频调速在桥式起重机中的应用

本文介绍了PLC和交流变频调速技术在桥式起重机上的应用,并详细介绍了PLC控制的桥式起重机变频调速系统的硬件构成,以及系统软件的实现.     

双逆变变频调速技术在桥式起重机上的研究与应用

本文主要介绍了双逆变变频调速技术原理及在桥式起重机起吊电机控制系统的应用情况和效果。     

可编程控制器在桥式起重机上的应用

本文结合中型厂13＃行车实行的变频调速改造项目，对可编程控制器在桥式起重机上的应用进行分析和研究。可编程控制器在众多领域得到推广应用，由可编程序控制器（PLC）实行集中控制、连锁保护，优化了起重机控制系统，提高了劳动效率。     

无线遥控及变频调速在起重机上的应用

介绍了使用凸轮控制器切换电阻来调速的桥式起重机进行无线遥控、变频调速的改造方案,阐述了无线遥控系统、变频器、PLC、触摸屏在桥式起重机中的应用.     

变频调速在桥式起重机上应用的理论研究

本文在对变频器工作原理和基本构成进行分析的基础上，对变频调速技术在桥式起重机上的应用进行了理论研究和探讨。     

基于PLC及变频器的行车控制系统改造

在冶金企业中,桥式起重机是一种应用十分广泛的起重机械。传统的继电器-接触器控制系统和串级调速方式存在能耗高、调速性能差、故障率高、安全性能低等问题。本文介绍了棒材厂圆棒车间基于PLC及变频器的桥式起重机(下文简称为行车)控制系统的改造设计,以提高行车的调速性能、安全性能,减少故障率并降低能耗。该系统自改造完成后,运行正常,达到设计目的。本设计方案具有通用性,对起重机控制系统设计改造具有参考价值。     

茂名石化炼油厂焦化桥式吊车变频调速控制系统

本文介绍了茂名石油化工公司炼油厂焦化桥式吊车变频调速控制系统工作原理及桥式吊车的变频调速控制改造情况。     

独山子石化炼油厂20吨桥式志重机变频调速研制报告

本文对独山子石化炼油厂20吨桥式起重机变频调速研制作了简述，对应用中出现的问题进行了总结，并予以解决。     

桥式起重机变频改造与无线遥控设计

针对普通桥式起重机普遍存在的一些问题和弊端,利用国产变频器和无线遥控器的性价比高的特点,研究了一种基于变频器和无线遥控器的桥式起重机电气控制系统的设计与应用。详细介绍桥式起重机变频改造的具体设计方案和变频器参数设置,给出了一种无线遥控器设计方案。实际应用结果表明这种电气控制系统极大地提高了起重机整机的控制可靠性和操作灵活性。     

桥式起重机的变频改造

针对企业使用的桥式起重机采用电动机转子串电阻进行起动和调速的传统方式,文章较为系统地对桥式起重机变频改造进行了详细介绍,改造后可以减小冲击电流,提高安全可靠性,降低能耗。     

桥式起重机双手柄抓斗控制系统改进

桥式起重机的抓斗使用双手柄操作,采用时间继电器方式控制,线路结构复杂,故障频率高.通过改用施耐德逻辑控制器ZELIO LOGIC及对控制线路的优化设计,解决了电机未启动前转子已完成切除电阻的隐患.在实践中证明：改进后的控制系统安全有效、运行稳定,接触器触点接触稳定良好,大大减少了故障率,提高了行车的工作效率.     

无触点低调速电控系统在桥式起重机上的应用

七十年代国家统一设计的桥式起重机系列电控设备存在许多缺点，随着科技的发展，新技术、新产品的不断开发。针对老式起重机电控系统进行全面改造，论文对新型的无触点交流低词速电控设备在交流桥式起重机上的应用进行简要论述。     

铝电解多功能机组新标准修订中关键问题研究

介绍了铝电解多功能机组的发展现状、现行标准的状况及标准修订的紧迫性及修订依据。在此基础上,对标准中铝电解多功能机组的结构型式、工作环境条件、生产安全等关键问题的修订进行了讨论:增加了铝电解多功能机组的结构型式,对铝电解车间磁场强度进行了分析和实测,对车间环境温度分布进行了计算流体动力学分析,约定了铝电解多功能机组的工作环境参数,同时结合桥式起重机、冶金起重机及绝缘起重机等现行标准,增加了铝电解多功能机组声光报警、控制联锁、标记指示及包装运输的安全要求。     

PLC系统在百米重轨吊运中的应用

介绍了用于多台独立吊车合车吊运百米重轨的PLC控制系统。系统采用西门子SIMATIC S7 PLC以及西门子PROFIBUS_DP现场总线控制技术,在多台吊车的PLC之间建立PROFIBUS_DP通讯连接,实现PLC与PLC之间的数据传输,以及PLC与上位机监控站的通信,使多台独立吊车在相互间没有任何物理联合的状态下,通过电气控制系统实现动作同步,实现多台吊车联合吊运百米重轨。     

采用PLC及调压调速技术改造桥式起重机

介绍了一种调速装置,通过与PLC配合对桥式起重机加以改造、控制后,使设备运行的稳定性、可靠性满足了生产需要,取得了良好的效果,提高了生产效率。     

塔式起重机智能监控系统的研制

塔式起重机（塔机）具有工作效率高、使用范围广、操作方便、安装拆卸容易等特点,在工业和民用建筑吊装作业中扮演着十分重要的作用,但减少塔机事故,提高塔机安全性能和作业效率一直是业界关心的问题。本系统以工控机为核心,采用视频监控技术、多传感器信息融合和神经网络等先进技术,使系统具有完备的控制功能、丰富的监测功能、稳定的性能、友好的界面和优良的性能价格比,并已在现场应用取得了良好的效果。     

Innovative System for Off-the-Ground Rotation of Long Objects Using Mobile Cranes

Managing heavy-pressure vessel lifts on construction sites requires planning, arranging adequate crane support, and preparing collision-free rotation (from a horizontal position to a vertical position) of the vessel. Generally, selecting mobile cranes and developing engineered lift studies for vessels are done using two cranes and analyzing the lift for each crane individually on the basis of the selected cranes’ lift-capacity specifications provided by crane manufactures. This practice is relatively costly and time-consuming. Optimizing the mobile cranes’ use and location is also difficult. To assist in the field operation of mobile cranes and to provide engineers with a planning tool, this paper presents a methodology to carry out such a lift utilizing only one crane. Using the developed methodology and mechanism, heavy vessels can be rotated off the ground (in the air) with one crane. The proposed mechanism is supported with a mathematical model that has been developed into a computer system and has been integrated with a previously developed crane selection and ground pressure calculation system and crane database. The developed system provides users with a lift study analysis for a given configuration as well as simulation results with interactive graphics to assist in the selection of an optimum configuration. This research is important as projects involving heavy lifts need to reduce the cost and time associated with construction operations.     

Curve Veering of Eigenvalue Loci of Bridges with Aeroelastic Effects

The eigenvalues of bridges with aeroelastic effects are commonly portrayed in terms of a family of frequency and damping loci as a function of mean wind velocity. Depending on the structural dynamic and aerodynamic characteristics of the bridge, when two frequencies approach one another over a range of wind velocities, their loci tend to repel, thus avoiding an intersection, whereas the mode shapes associated with these two frequencies are exchanged in a rapid but continuous way as if the curves had intersected. This behavior is referred to as the curve veering phenomenon. In this paper, the curve veering of cable-stayed and suspension bridge frequency loci is studied. A perturbation series solution is utilized to estimate the variations of the complex eigenvalues due to small changes in the system parameters and establish the condition under which frequency loci veer, quantified in terms of the difference between adjacent eigenvalues and the level of mode interaction. Prior to the discussion of bridge frequency loci, the curve veering of a two-degree-of-freedom system comprised of a primary structure and tuned mass damper is discussed, which not only provides new insight into the dynamics of this system, but also helps in understanding the veering of bridge frequency loci. To study this more complicated dynamic system, a closed-form solution of a two-degree-of-freedom coupled flutter is obtained, and the underlying physics associated with the heaving branch flutter is discussed in light of the veering of frequency loci. It is demonstrated that the concept of curve veering in bridge frequency loci provides a correct explanation of multimode coupled flutter analysis results for long span bridges and helps to improve understanding of the underlying physics of their aeroelastic behavior.     

自动控制的变频调速系统在抓斗吊中综合应用

宝钢二炼钢水处理桥式抓斗吊原设计为继电器连锁控制切除电阻的调速,该方式故障频率高,维护成本高。采用变频器和PLC控制进行升级改造后,各项功能大为改善,取得了良好的效果。主要针对PLC、变频器的选型及组态,自动控制的变频调速系统调试方法等进行了介绍。     

TSC动态无功补偿原理与在天车上的应用

介绍武钢第一炼钢厂在天车上采用TSC动态无功补偿系统,概述了该系统的主回路、控制系统、软件设计以及采用无功补偿装置后,取得的经济效益。