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Based on analysis of submerged arc welding arc heat source model and droplet heat inputting uniform distribution, ANSYS parametric design language was applied to develop sub-program for loading moving heat sources. ANSYS software was used to calculate the temperature fields. In the same welding conditions, weld seam width and depth value of experiments and simulation are contrasted, the biggest error was below 5%. The influence of different welding speed to molten pool temperature of twin-arc submerged arc welding was analyzed, it obtained results that temperature field distribution of twin-arc submerged arc welding changes more gentle than single arc submerged arc welding in condition of increased welding speed, it was helpful to the further analysis of molten pool dynamic behavior and weld seam shape factors of twin-arc high speed submerged arc welding.

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Twin-Arc high-speed submerged arc welding forming quality prediction model was developed by three layers BP (Back Propagation) neural network. In the model, twin arc current, twin arc voltage, welding speed and wire spacing are selected for the study factor, weld pool width and penetration depth are weld forming quality indicators. The adaptive learning rate and additional momentum term are introduced to improve BP algorithm. Experiments show that the network structure is reasonable of the nodes by inputting and outputting layers of 6 and 2 respectively, hidden layer nodes are 13. The developed neural network model can predict the weld geometry with high computing and predictive accuracy of maximum predictive validation error of weld width and penetration depth within 9.6%, 10.3% respectively, which can be used for real-time monitoring of the quality of welding in the twin arc high-speed submerged arc welding process.

This paper presents the dynamics-simulation and research of vibration characteristic on deep-groove ball bearing. It introduces an analysis of the vibration frequency in different damage of bearing and spectrum analysis of the fault signal on bearing to draw response on vibration characteristics in bearing, so as to provide a simple method on research of dynamic fault characteristic of bearing. This work shows some kind, characteristics signal and frequency of fault on bearing. The normal model and other two models which have raceway crack in inside track and out ring are set up by using ADAMS software to analyse the dynamic of them, the test program that vibration signal of three models are obtained by acceleration sensors to instead of that of real condition is simulated. In addition, the test signal of vibration is given in time domain respectively, and the vibration characteristic is identification by using spectrum analysis method, so that it can provides technical support for diagnosis of fault bearing. In the study of fault diagnosis, several experimental results provide that the uncertainty of fault diagnosis and interference of other complicated factors are avoided effectively in real environment. The result of simulated analysis is consistent with the theory calculation. This method is more effective, convenient and expansibility than a research of practical fault-diagnosis.