Simulation And Experimental Research On Local Continuous Induction Heating Of Inner Corrugated Section

The pressure resistant shell section is the core basic component of the deep sea equipment,and the pressure resistant shell with inner corrugated structure can significantly improve the pressure resistant performance.Currently,the corrugated section,rolled out through the corrugated roll,has complex shape,long production cycle,and large surface temperature drop,which leads to low surface temperature.Meanwhile,lower rolling temperature will lead to larger deformation resistance which affects plastic forming,increases the load of the rolling mill,and produces the instability in size and shape control of the inner corrugated section.This paper will study the local continuous induction heating technology of the inner corrugated section,which is conducive to breaking the bottleneck of manufacturing in the inner corrugated section and has great significance for rolling forming of the inner corrugated section.First,for the structure of the inner corrugated section,rectangular,profiling,and antiprofiling coils were designed respectively.Then the overall heating was completed through the induction coil that was used to perform continuous heating to the local position of the inner corrugated section.Second,a mathematical model of the local continuous induction heating electromagnetic field and temperature field of inner corrugated section was established,and a finite element model of inner corrugated section with electromagnetic induction heating was established by finite element software ANSYS.And then the two-way realtime coupling simulation of inner corrugated electromagnetic field and temperature field was completed.According to the above operations,the temperature distribution law of the internal corrugated section in the process of electromagnetic induction heating rolling forming was revealed,at the same time,the influence,caused by coil structure,electricity,frequency and air gap,on the induction heating results of the inner corrugated section was analyzed.Finally,an experimental platform for induction heating of the inner corrugated section was built,rectangular,profiling,anti-profiling coil and inner corrugated section sample were made.Initially these three coils were used to conduct the induction heating experiment for the inner corrugated section,at the same time,the surface temperature change of the inner corrugated section was measured by thermocouple during the process of induction heating.Comparing and analyzing the experimental results,it was concluded that the profiling coil had high heating efficiency and good uniformity,which is consistent with the simulation results.And then by changing the air gap,the influence of the air gap on the experimental results of induction heating was studied and analyzed.Both the experimental and simulation results showed that when the air gap was reduced,the efficiency of induction heating was improved,but the uniformity was deteriorated.