Research On Welding Temperature Measurement And Control Of Hi-frequency Welded Pipe And Temperature Field Numerical Simulation

High-frequency welding temperature is an important processing parameters in pipe production, it is directly related to the welding process whether establish correctly and directly affect the weld quality. So, the welding temperature control is very important。In traditional high-frequency welding process, welding temperature is only observed by workers and manual adjust Power of High Frequency Power Supply Output or welding speed to achieve, so the quality of pipes is unstable. In foreign industrial countries non-contact infrared thermometer has been used in high-frequency welding temperature control system, and relatively strong job stability。Infrared temperature measurement technology in industry research has matured in China, and relative technical studies are carried out in domestic high-frequency welding machine, and achieved good results. But in the long-term of production, it lacks stability.In this paper, mainly research and analysis on the stability of the infrared thermometer used in the domestic high-frequency welding machine has carried out. The main work is summarized below.Analyzed and summarized the theoretical basis and the basic principles of infrared thermometer and the various factors which affect the normal temperature of the infrared thermometer; gives the calculation formula of the three important parameters which impact of high-frequency welded pipe welding quality, as well as weld quality affected by the respective parameters of under the conditions of other parameters unchanged.In the production process of hi-frequency welded pipe, real-time monitoring and automatic regulating the temperature at weld is of great significance to improve the quality of hi-frequency welded pipe, The paper introduces that how the colorimetric pyrometer is used in the automatic control system of hi-frequency welded pipe. Through analysis and research the gathered date which is based on the experiment, summarizing the causation which caused the colorimetric pyrometer unstable operation and the solving methods, and bring forward improvement advices.A finite element model of three-dimensional dynamic thermal distributions of ERW was established. The APDL program was written with the finite element analysis (FEA) software ANSYS to simulate the welded seam of ERW pipe. The infrared temperature measuring meter Raytek MarathonTM FA/FR measures the welding process. The numerical solution and experimental results show good agreement and effectiveness of the analytic model.