Stress Analysis And Optimization Of The Ultra-high Pressure Polythene Reactive Tube

The ultra-high pressure polythene reactive tube occupies an important position in the whole process of the polythene production. Therefore, in this paper a ultra-high pressure polythene reactive tube of YANSHAN petroleum and chemistry corp. has been investigated. The ANSYS5.7 finite element software has been used to analyze the stress of the ultra-high pressure reactive tube. Basing on analyzing the stress, it's found that the preheat section of the ultra-high pressure reactive tube was on the verge of insecurity. It's also found that the safety will be enhanced, if autofrettage has been applied.In this paper, an optimization program for the elastic-plastic interface radius of the tube has been worked out in Turbo C language to obtain its optimum value as well as the most rational stress state in the wall of the tube. "The software of calculation and analysis for the ultra-high pressure reactive tube" for studying the stress state of the wall of the tube has also been worked out completely with the Turbo C language. The software can not only simulate the stress state of the tube under the condition of elasticity, plasticity, elasticity-plasticity and the stable thermal field, but also include the optimization program of the ultra-high pressure reactive tube and the interface program about the ANSYS finite element. So the software might be considered as a relatively general software of calculation and analysis, which can carry out analytic calculation, numeric calculation and optimization.In summary, the stress analysis, the stress intensity evaluation and the optimization for the ultra-high pressure polythene reactive tube have been carried out. All of these will make a good base for the safety of the reactive tube. While there is no design criterion about ultra-high pressure vessel in our country, the research of this paper will provide some references for constituting a criterion. In addition, the software may also be used in the on-line inspection of the ultra-high pressure reactive tube.