关键词: 超高压管道, 壁厚, 许用应力, 疲劳分析, 静压设计

Abstract: The wall thickness design of ultra-high pressure pipeline is related to material properties, design conditions and calculation methods. For the ultra-high pressure pipeline with nominal pressure greater than PN420, there is no corresponding design standard in China. At present, it is designed according to international standards. Taking American Standard as an example, there are two wall thickness calculation methods: conventional pipeline and high-pressure pipeline. It is considered that the pipeline with pressure not exceeding 70 MPa can be calculated according to the conventional pipeline without fatigue analysis. Therefore, the design, wall thickness calculation and value of ultra-high pressure pipeline bearing internal pressure are discussed. Taking a working condition of a unit as an example, comparing the calculation results according to different methods, it is found that thickness by conventional pipeline calculation is very close to or more than D/6 (D is the outer diameter of the pipe), and the fatigue analysis is also essential. Therefore, for the ultra-high pressure pipeline with nominal pressure greater than PN420, the wall thickness shall be designed according to the high pressure pipeline, and the fatigue analysis shall be carried out. The fatigue analysis of internal pressure straight pipe can be analyzed in detail by finite element method, evaluated by calculating the compressive stress, or verified by twice the internal design pressure.    

Key words: ultra-high pressure pipeline, wall thickness, allowable stress, fatigue analysis, static pressure design