| In the industrial production and manufacturing industry,electric welding technology has important significance.The welding equipment is small in size and high in efficiency.It is widely used in the field of machinery manufacturing such as railway,aerospace,and shipping.However,arc welding equipment is usually accompanied by strong light,toxic gas,smoke,and large electromagnetic pollution.The low-frequency radiation of the high-power welding machine is mainly reflected in the low-frequency magnetic field.When the welding current passes through the welding cable,a magnetic field is generated around it.In the past 20 years,there have been continuous scientific research institutions to investigate whether the low-frequency magnetic field generated by the welding machine will cause harm to the human body.In order to solve the problem of electromagnetic exposure in welding operations,the spatial magnetic field distribution during welding and the magnetic field distribution inside the human body are calculated,the safety of the electromagnetic environment around the welding machine during welding is evaluated,and the influence of the electromagnetic field of the welding cable during the welding process on the human body is quantitatively analyzed,To provide a healthy basis for welding operators.First,the paper briefly describes the development process of the electric welding machine,introduces several important changes in the arc welding power supply,clarifies the main source of electromagnetic disturbance in the welding process,and provides a basis for the simulation experiment.In order to effectively evaluate the impact of the magnetic field generated during the welding process of the high-power welding machine on the human body,the standard limits specified in the ICNIRP guidelines are used as the evaluation standard for evaluating the electromagnetic environment when the welding machine is working.The finite element software ANSYS was used to establish the human body model of the welding operator,and the simulation environment was established with reference to the welding environment.Secondly,the welding environment model is established in ANSYS software,and the human body model is added to simulate the magnetic field distribution inside the human body during welding.During the welding process,the welding current changes according to the requirements of the workpiece.During the calculation,the DC welding cable is used as the excitation source,and the magnetic field intensity distribution in the space field and inside the human body is calculated by applying different current loads.The experimental results show that the current carried by the welding cable and the change of the welding cable’s position from the human body have an influence on the distribution of the magnetic field generated by the welding cable inside the human body.When the output current of the welding machine reaches 500 A and the welding cable is close to the human body,the magnetic induction intensity generated by the welding cable in the human body reaches the peak.The ANSYS calculation result is 63.4 μT,accounting for 63.4% of the ICNIRP standard,which is less than the occupational exposure threshold of ICNIRP2010.Therefore,from the simulation results,the magnetic field generated by the welding cable does not pose a health risk to the human body.Finally,according to the simulation environment,the magnetic field generated by the welding machine of the same type is measured on the spot,and the magnetic induction intensity of the welding machine and the welding cable during the welding process is measured.When the welding power source outputs a large current(500A)and the welding cable is very close,the magnetic induction intensity generated inside the human body reaches the peak of the experiment,which is the same as the rule of the simulation result.By comparing and analyzing the simulation results with the measurement results,it is known that the error between the measurement results and the simulation results is within 10%,which proves that the experimental data is reliable.It is concluded that when the welding power source outputs a large current(500A)and the welding cable is very close to the human body,the magnetic induction intensity generated inside the human body reaches the experimental peak.The maximum magnetic induction intensity of the cable in the waist,wrist and other parts is 63.4% of the ICNIRP standard The magnetic field generated by the cable does not pose a health risk to the practitioner.When the output current of the welding cable is reduced,and the output current is 400 A,200A,and 100 A in sequence,the generated magnetic induction intensity accounts for 50%,21%,and 11% of the ICNIRP standard,which gradually decreases;and when the distance between the welding cable and the human body When increased to 0.1m,these values become 13%,5%,and 2.6%,respectively.It shows that during the welding process,the change of output current has an effect on the distribution of the magnetic field generated by the welding cable.The magnetic induction intensity is positively related to the current size;the distance from the welding cable determines the magnitude of the magnetic induction intensity and the magnetic induction intensity at the same position Inversely related to distance.We compare the simulation results with the measurement results of the welding process,the experimental results of the two are very close,proving that the simulation experiment is a scientific and effective experimental method. |
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