Study Of System Automation Process For Forming Weld Seam In Multi-pass Welding

By now,the most commonly utilized welding process in the world is arc welding in the compound metal structures,thus takes arc welding with consumable electrode in the environment carbonic gas and under flux.When carried out welding work still has a high proportion of manual labor.Automating this process is hampered by a lack of reliable and highly accurate mutual position sensorsfor the welding head and the set welding joint.Exist sensors(mechanical,thermal,and optical)are not currently used because in welding,the spatter zone includes arise molten metal,gases and other ad verse factors hindering their work.Recently,the most promising use of the arc as a sensor depends on the progress,such as the parameters of joint edges,gaps in the individual components of the welding current and voltage.The use of the arc as a source of information on the relative positions of the welding head and the joint are based on the use of mathematical models predicting the process.The problem of joint finding and guidance electrode to the joint has been solved.However,to get a good connection,multi-pass welding needs to know information about the parameters of cutting and the presence of gaps in each moment of welding.The purpose is to improve the accuracy of the welding head position relative to the joint based on instantaneous values ana lysis of welding current,taking into account information about the welding joint profile at the multi-pass welding and data collection about the welding process for further analysis.This research used the methods of automatic control theory,numerical analysis,signal filtering theory and the theory of digital signal processing.To confirm the reliability and the efficiency of the developed scheme,the automatic welding process is carried out by computer simulation research.Practical value of the wo rk consists in theproposed new structure of the automatic welding process,software and circuit solutions.Some control systems have been developed for automatic welding equipment as well as systems for collecting and processing parameters of the welding process.The use of the proposed automatic system in practice can improve weld quality,increase productivity and reduce the cost of electricity and welding materials.After analysis of references on automatic control system of welding processes,it was concluded that the problem of determining position of the welding head relative to the joint,with the use of electric arc parameters,theoretical and practical solutions have not been resolved although the amount of scientific and technical information on this subject is increasing.Control models describing arc welding process are developed to define the parameters of the welding current and voltage at different positions of the welding head and joint parts.Also,an engineering method for obtaining information on deviations from the set parameters of the torch relative to joint basis on the instantaneous values of welding current analysis was developed.A linear function approximation carried out by the polynomial of the second and 3rd degree.The obtained results have the potential to significantly expand thepractical application scopepractical application of the automatic systems welding process,remove the existing contradictions between the increasing quality requirements of the welding process,and the technical feasibility of automatic devices in this class.