A general industrial CCD( ICCD) camera is redesigned to detect the weld pool without arc at the period of short circuiting, so that the interference of arc and spatter during CO2 short circuiting arc welding is elim...A general industrial CCD( ICCD) camera is redesigned to detect the weld pool without arc at the period of short circuiting, so that the interference of arc and spatter during CO2 short circuiting arc welding is eliminated. Through the analysis of weld pool image, both size parameters (such as weld pool area A, weld pool length L1, L2 and weld pool breadth b) and contour parameters (b, which describe the curves of weld pool boundany) ,which could indicate the shape features of weld pool, had been defined to express weld pool information quantitatively. The investigation of the relationships between weld pool shape parameters and welding process parameters may be beneficial to the quality control of CO2 welding.展开更多
Based on the chaos theory, an idea is put forward to analyze the short circuit Gas Metal Arc Welding ( GMAW-S) process. The theory of phase space reconstruction and related algorithms such as mutual information and ...Based on the chaos theory, an idea is put forward to analyze the short circuit Gas Metal Arc Welding ( GMAW-S) process. The theory of phase space reconstruction and related algorithms such as mutual information and so on, are applied to analyze the chaos of the GMAW-S process. The largest Lyapunov exponents of some current time series are calculated, and the results indicate that chaos exists in the GMAW-S process. The research of the chaos in the GMAW-S process can be help to get new knowledge of the process.展开更多
In order to detecting and tracking along the weld seam with rotating arc sensor in underwater welding,the highpressure water environment rotating arc welding hardware platform is established and welding experiments us...In order to detecting and tracking along the weld seam with rotating arc sensor in underwater welding,the highpressure water environment rotating arc welding hardware platform is established and welding experiments using rotating arc sensor is done. Different radius of rotating arc sensor is used. And the corresponding welding current and voltage is obtained,which is compared with the results of rotating arc sensor short-circuit process simulation model under high-pressure water environment established in this article. The results show that under high-pressure water environment,rotating arc radius should be optimized,otherwise the short-circuit-arcing cycle will transit to a short-circuit-arcing-abruption cycle,making the welding quality poor. At last the critical radius between the short-circuit-arcing cycle and short-circuit-arcing-abruption cycle under high-pressure water environment is obtained.展开更多
Aim at improving the stability of the Short-circuiting Gas Metal Arc Welding (GMAW-S) process for the enhanced speed usage, effects of current waveform parameters during short-term on the welding stability have been...Aim at improving the stability of the Short-circuiting Gas Metal Arc Welding (GMAW-S) process for the enhanced speed usage, effects of current waveform parameters during short-term on the welding stability have been investigated by experimental method. The welding power source used for the research is an inverter with a special current waveform control. It is shown that the spatter decreases at first then increases with each increase of the low current period, current increase rate and the maximum current limit. The test results are provided for welding of 1 mm and 3 mm mild steel at speed of 1.2 m/min. The stable GMA W-S process under high speed welding condition has been achieved by optimizing the parameters.展开更多
Based on the phase space reconstruction of welding current in short-circuiting transfer arc welding under carbon dioxide, the approximate entropy of welding current and its standard deviation have been calculated and ...Based on the phase space reconstruction of welding current in short-circuiting transfer arc welding under carbon dioxide, the approximate entropy of welding current and its standard deviation have been calculated and analyzed at different welding speeds and different electrode extensions respectively. The experimental and calculated results show that at a certain arc voltage, wire feeding rate and gas flow rate, welding speed and electrode extension have significant effects not only on the approximate entropy of welding current, but also on the stability of welding process. Further analysis proves that when the welding speed and electrode extension are in an appropriate range respectively, the welding current approximate entropy attains maximum and its standard deviation minimum. Just under such circumstances, the welding process is in the most stable state.展开更多
A new simulation model of CO 2 short circuiting transfer welding may be employed to develop a new pattern of welding machine and to predict welding process parameters to obtain the optimum welding technology propert...A new simulation model of CO 2 short circuiting transfer welding may be employed to develop a new pattern of welding machine and to predict welding process parameters to obtain the optimum welding technology properties. In this paper, a new simulating model is developed according to the AWP (adapting welding physics process) waveform control method. Good agreement is shown between the predicted and experimentally determined results. The model will make an important promotion in the development of CO 2 arc welding technique.展开更多
An intelligent fuzzy c-means system for process monitoring and recognition of process disturbances during short- circuiting gas metal arc welding (GMAW) is introduced in this paper. The raw measured and statisticall...An intelligent fuzzy c-means system for process monitoring and recognition of process disturbances during short- circuiting gas metal arc welding (GMAW) is introduced in this paper. The raw measured and statistically test data of probability density distribution ( PDD ) and class frequency distribution ( CFD ) of welding electrical parameters are further processed into a 7-dimensional array which is designed to describe various welding conditions, and is employed as input vector of the intelligent fuzzy c-means system. The fuzzy c-means system is used to conduct process monitoring and automatic recognition. The correct recognition rate of 24 test data under 8 kinds of welding condition is 92%.展开更多
通过综合运用数据采集卡的模拟输入输出功能以及高速摄像的外部触发功能,利用虚拟仪器LABVIEW和高速摄像设备,开发了一套弧焊参数采集与分析系统。该系统可以对焊接过程的电信号信息和熔滴过渡图像信息同步采集,并对采集的电信号进行滤...通过综合运用数据采集卡的模拟输入输出功能以及高速摄像的外部触发功能,利用虚拟仪器LABVIEW和高速摄像设备,开发了一套弧焊参数采集与分析系统。该系统可以对焊接过程的电信号信息和熔滴过渡图像信息同步采集,并对采集的电信号进行滤波处理、统计分析、U-I分析、相关性分析、FFT变换、STFT变换、功率谱分析等时域和频域的分析。将该系统应用于GMAW(gas metal arc welding)过程中,通过综合分析电信号与熔滴过渡图像的关系以及焊接电流变异系数与频率的关系,可以直观地反映出焊接过程稳定性和电信号与熔滴过渡的关系,为波形控制和熔滴过渡控制提供理论依据,有利于优化GMAW过程。展开更多
基金This project is supported by National 863 project( No.412-9913-02)and National Natural Science Foundation of China(No.599750
文摘A general industrial CCD( ICCD) camera is redesigned to detect the weld pool without arc at the period of short circuiting, so that the interference of arc and spatter during CO2 short circuiting arc welding is eliminated. Through the analysis of weld pool image, both size parameters (such as weld pool area A, weld pool length L1, L2 and weld pool breadth b) and contour parameters (b, which describe the curves of weld pool boundany) ,which could indicate the shape features of weld pool, had been defined to express weld pool information quantitatively. The investigation of the relationships between weld pool shape parameters and welding process parameters may be beneficial to the quality control of CO2 welding.
基金The work was supported by National Natural Science Foundation of China (No 50375053,50575077)
文摘Based on the chaos theory, an idea is put forward to analyze the short circuit Gas Metal Arc Welding ( GMAW-S) process. The theory of phase space reconstruction and related algorithms such as mutual information and so on, are applied to analyze the chaos of the GMAW-S process. The largest Lyapunov exponents of some current time series are calculated, and the results indicate that chaos exists in the GMAW-S process. The research of the chaos in the GMAW-S process can be help to get new knowledge of the process.
基金supported by the National Natural Science Foundation of China(Grant No.51665016)founded by the China Scholarship Council(Grant No.201508360113)
文摘In order to detecting and tracking along the weld seam with rotating arc sensor in underwater welding,the highpressure water environment rotating arc welding hardware platform is established and welding experiments using rotating arc sensor is done. Different radius of rotating arc sensor is used. And the corresponding welding current and voltage is obtained,which is compared with the results of rotating arc sensor short-circuit process simulation model under high-pressure water environment established in this article. The results show that under high-pressure water environment,rotating arc radius should be optimized,otherwise the short-circuit-arcing cycle will transit to a short-circuit-arcing-abruption cycle,making the welding quality poor. At last the critical radius between the short-circuit-arcing cycle and short-circuit-arcing-abruption cycle under high-pressure water environment is obtained.
文摘Aim at improving the stability of the Short-circuiting Gas Metal Arc Welding (GMAW-S) process for the enhanced speed usage, effects of current waveform parameters during short-term on the welding stability have been investigated by experimental method. The welding power source used for the research is an inverter with a special current waveform control. It is shown that the spatter decreases at first then increases with each increase of the low current period, current increase rate and the maximum current limit. The test results are provided for welding of 1 mm and 3 mm mild steel at speed of 1.2 m/min. The stable GMA W-S process under high speed welding condition has been achieved by optimizing the parameters.
基金Supported by Project of the National Natural Science Foundation of China(50375053,50575077)
文摘Based on the phase space reconstruction of welding current in short-circuiting transfer arc welding under carbon dioxide, the approximate entropy of welding current and its standard deviation have been calculated and analyzed at different welding speeds and different electrode extensions respectively. The experimental and calculated results show that at a certain arc voltage, wire feeding rate and gas flow rate, welding speed and electrode extension have significant effects not only on the approximate entropy of welding current, but also on the stability of welding process. Further analysis proves that when the welding speed and electrode extension are in an appropriate range respectively, the welding current approximate entropy attains maximum and its standard deviation minimum. Just under such circumstances, the welding process is in the most stable state.
基金ThisresearchissupportedbytheNationalNatureScienceFoundation (No .5 9975068)andTianjinNatureScienceFoundation (No .993 60 2 911)
文摘A new simulation model of CO 2 short circuiting transfer welding may be employed to develop a new pattern of welding machine and to predict welding process parameters to obtain the optimum welding technology properties. In this paper, a new simulating model is developed according to the AWP (adapting welding physics process) waveform control method. Good agreement is shown between the predicted and experimentally determined results. The model will make an important promotion in the development of CO 2 arc welding technique.
基金The authors are grateful to the financial support provided by the National Natural Science Foundation of China under grant No. 51005106, Research Fund for the Doctoral Program of Jiangsu Uni- versity of Science and Technology under grant No. 35060902, A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘An intelligent fuzzy c-means system for process monitoring and recognition of process disturbances during short- circuiting gas metal arc welding (GMAW) is introduced in this paper. The raw measured and statistically test data of probability density distribution ( PDD ) and class frequency distribution ( CFD ) of welding electrical parameters are further processed into a 7-dimensional array which is designed to describe various welding conditions, and is employed as input vector of the intelligent fuzzy c-means system. The fuzzy c-means system is used to conduct process monitoring and automatic recognition. The correct recognition rate of 24 test data under 8 kinds of welding condition is 92%.
文摘文中提出了一种基于压电致动器的高动态焊丝启停控制技术,压电致动器膨胀锁止焊丝,收缩则释放焊丝.在焊丝锁止-释放过程中,可以主动驱动熔滴与熔池短路,并利用这一动态过程产生的惯性力驱动短路液桥断裂完成一次熔滴过渡.研究结果表明,组合压电致动器的加入对于小电流下GMAW短路过渡有显著的改善,短路开始和结束都稳定可控,避免了随机短路的发生,不再依赖大短路电流强制缩颈液桥,短路过渡频率显著提升,在DCEP 100 A焊接电流下可达130 Hz,DCEN模式下由于阴极斑点爬升导致电弧稳定性较差,但短路过渡频率也可达100 Hz.
文摘通过综合运用数据采集卡的模拟输入输出功能以及高速摄像的外部触发功能,利用虚拟仪器LABVIEW和高速摄像设备,开发了一套弧焊参数采集与分析系统。该系统可以对焊接过程的电信号信息和熔滴过渡图像信息同步采集,并对采集的电信号进行滤波处理、统计分析、U-I分析、相关性分析、FFT变换、STFT变换、功率谱分析等时域和频域的分析。将该系统应用于GMAW(gas metal arc welding)过程中,通过综合分析电信号与熔滴过渡图像的关系以及焊接电流变异系数与频率的关系,可以直观地反映出焊接过程稳定性和电信号与熔滴过渡的关系,为波形控制和熔滴过渡控制提供理论依据,有利于优化GMAW过程。