Optimisation of the weld bead geometry in gas tungsten arc welding by the Taguchi method

In this paper, determination of the welding process parameters for obtaining an optimal weld bead geometry in gas tungsten arc welding is presented. The Taguchi method is used to formulate the experimental layout, to analyse the effect of each welding process parameter on the weld bead geometry, and to predict the optimal setting for each welding process parameter. Experimental results are presented to explain the proposed approach.     

空间焊缝弧焊机器人焊接路径自动规划研究

开发了面向空间焊缝的弧焊机器人焊接路径自动规划系统。该系统以VB6．0为编程平台，能够实现由三维实体模型直接生成机器人焊枪的位姿文件，进一步地输出为机器人语言程序，采用UP6弧焊机器人系统和S-350MAG焊接系统实际焊接，实验结果验证了该系统的正确性。     

反应堆CRDM钩爪堆焊工艺仿真研究

基于有限元软件建立了钩爪堆焊毛坯和终形模型,采用双椭球型热源模拟氧乙炔火焰,依照先堆焊两个内孔再堆焊齿面的顺序进行了瞬态热应力场仿真;根据探索得到的堆焊最优工艺进行零件试制,对钩爪堆焊半成品及成品件进行微观组织、渗透探伤和显微硬度检验.结果表明,由此堆焊优化方案制造的钩爪堆焊件质量优良.     

Adaptive fuzzy sliding mode control for an automatic arc welding system

This paper describes an automatic welding control system developed for alternating current shielded metal arc welding (SMAW). This method could replace manual operations which require a well-trained technician. We have derived a mathematical model of the welding control system and identified the system’s parameters. The sliding surface is used as the input variable to reduce the number of fuzzy reasoning rules, in comparison with the conventional two-dimensional fuzzy logic control (FLC) algorithm. An adaptive fuzzy sliding mode controller (AFSMC) consists of an equivalent control part and a hitting control part. An adaptive law derived from a Lyapunov function is used to obtain the FLC’s parameters, and is applied to approximate the equivalent control part of the sliding mode control (SMC), so that the system states can be forced to zero. By using three-rules FLC, the control part that satisfies the hitting conditions of the SMC can force the system’s states to reach and remain on the sliding surface. Therefore, the stability of the AFSMC can be guaranteed and can be used to modulate the rate of the electrode feeding mechanism that regulates the arc current of the SMAW. The simulation and the experimental results both show that this automatic welding control system, based on the AFSMC, can perform effectively.     

Adaptive fuzzy sliding mode control for an automatic arc welding system

This paper describes an automatic welding control system developed for alternating current shielded metal arc welding (SMAW). This method could replace manual operations which require a well-trained technician. We have derived a mathematical model of the welding control system and identified the system’s parameters. The sliding surface is used as the input variable to reduce the number of fuzzy reasoning rules, in comparison with the conventional two-dimensional fuzzy logic control (FLC) algorithm. An adaptive fuzzy sliding mode controller (AFSMC) consists of an equivalent control part and a hitting control part. An adaptive law derived from a Lyapunov function is used to obtain the FLC’s parameters, and is applied to approximate the equivalent control part of the sliding mode control (SMC), so that the system states can be forced to zero. By using three-rules FLC, the control part that satisfies the hitting conditions of the SMC can force the system’s states to reach and remain on the sliding surface. Therefore, the stability of the AFSMC can be guaranteed and can be used to modulate the rate of the electrode feeding mechanism that regulates the arc current of the SMAW. The simulation and the experimental results both show that this automatic welding control system, based on the AFSMC, can perform effectively.     

Development of mathematical models for prediction of weld bead geometry in cladding by flux cored arc welding

The mechanical and corrosion resistant properties of cladded components depend on the clad bead geometries, which in turn are controlled by the process parameters. Therefore it is essential to study the effect of process parameters on the bead geometry to enable effective control of these parameters. The above objective can easily be achieved by developing equations to predict the weld bead dimensions in terms of process parameters. Experiments were conducted to develop models, using a three factor, five level factorial design for 317L flux cored stainless steel wire with IS:2062 structural steel as base plate. The models so developed were checked for their adequacy. Confirmation experiments were also conducted and the results show that the models developed can predict the bead geometries and dilution with reasonable accuracy. It was observed from the investigation that the interactive effect of the process parameters on the bead geometry is significant and cannot be neglected.     

A visual seam tracking system for robotic arc welding

A novel circular laser three-dimensional (3D) scanner is developed instead of a one-dimensional laser spot scanner (1D) and two-dimensional (2D) striped laser light. Using the proposed circular laser scanner, a seam tracking system is constructed, and architecture based on the Visual C++ and RAPID languages which determines the cooperation among image processing modules is carried out. Finally, real seam tracking experiments are investigated and the error analysis is carried out. The results show that: (1) the proposed system can realize seam tracking; (2) the precision of this system is affected by the light scanning system, calibration results, image processing, and the welding seam 3D algorithm—the tracking accuracy is satisfied for robotic arc welding; (3) this system can be used in a welding robot system as a weld seam finder, flatness detector, and weld seam tracker.     

Mathematical models for control of weld bead penetration in the GMAW process

This paper presents the effects of welding process parameters on weld bead penetration for the gas metal arc welding (GMAW) process. Welding process parameters included wire diameter, gas flow rate, welding speed, arc current and welding voltage. The experimental results have shown that weld bead penetration increased as wire diameter, arc current and welding voltage increased, whereas an increase in welding speed was found to decrease the weld bead penetration. However, the weld bead penetration is not affected significantly by gas flow rate changes. Mathematical equations for study of the relationship between welding process parameters and weld bead penetration have also been computed by employing a standard statistical package program, SAS.     

集装箱外焊缝自动抛丸清理设备检测控制系统设计

针对集装箱外焊缝自动抛丸清理设备,设计了检测控制系统。该系统利用PLC作为控制核心,采用激光测距传感器来检测垂直焊缝。传感器被固定在生产线的一侧,集装箱在生产线上流水性通过。当焊缝经过激光传感器前时,激光传感器会检测到距离突变,通过算法可判断出焊缝经过的时刻。在此基础上,PLC可以控制抛头,使磨料准确地抛打清理焊缝。     

浅谈MAG焊和埋弧焊在箱式井架的应用

从箱式井架的结构形状和焊缝接头形式出发,针对MAG焊和埋弧焊的特点进行了论述,生产结果证明,通过两种优质、高效方法的运用,使焊接质量得到了保障,生产效率得到很大提高.     

铝合金双面自动 TIG立焊计算机控制系统

为实现空分设备的焊接自动化，本文研究了铝合金双面自动TIG立焊二级分布计算机控制系统，此系统的硬件包括5个子系统，即：焊接电源，弧长控制器，焊矩行走机构和检测机构，软件包括在线执行程序和离线服务程序。介绍了此系统的操作原理，规范说明和控制功能，解决了对计算机控制系统的高频干扰问题，使系统工作稳定，控制精度高，采用汉语菜单，操作方便。     

基于HP VEE的超声波塑料焊接温度场检测系统

由于超声波塑料焊接具有升温速度快、局部生热、压力作用的特点使其温度场测量非常困难.文中采用基于HP VEE的温度场测量系统来测量超声波塑料焊接的温度场;并介绍了HP VEE的功能、该温度场测量系统的组成和采用该系统进行的超声波焊接PVC塑料的温度场检测试验.试验表明该系统能够高精度、快速、自动的检测超声波塑料焊接温度场.     

基于DSP的闪光焊机电源的数字化设计及电路仿真

介绍了基于数字信号处理器(DSP)的闪光焊机电源的数字控制系统的设计,具体讨论了控制焊机电源的硬件结构和仿真电路设计,重点介绍了闪光焊机电源的主回路、数字同步和触发电路、控制电路的键盘、显示电路和采样电路等。利用Pspice和Multisim对主电路和同步扑捉电路进行了仿真和分析。仿真结果表明,该焊机电源的电路结构性能高,能够满足闪光焊机电源的工艺要求。     

一种基于ARM的钢管焊渣条分叉视觉检测系统

采用机器视觉技术,设计了一种基于ARM、以USB网络摄像头采集图像的焊渣条分叉自动检测系统。对图像进行二值化处理后,系统根据对象边缘像素点的分布识别焊渣条是否分叉,并驱动相应的声光报警器报警。试验证明,该系统能自动检测焊渣条分叉,体积小,性价比高,在低速低精度的检测场合具备较高的推广应用价值。     

基于CAN总线的LED隧道灯控制系统设计

介绍了一种基于CAN总线的LED隧道灯控制方法,利用CAN总线传输距离远、成本较低、可靠性高的特点,实现控制长距离隧道内LED隧道灯工作的目的。给出了系统组成框图和工作原理。     

基于BP神经网络的火电厂水质调节系统的Smith-PID自适应控制

针对火电厂水质调节系统大时滞时变性的特点,提出了基于BP神经网络的Smith-PID控制算法,仿真研究和实际应用表明,该控制算法具有良好的静态特性、动态品质和很强的鲁棒性;工程应用控制效果令人满意。