The Thermal Stress And Creep Analysis Of The10×10~4Nm~3/h Hydrogen Production Conversion Furnace Tube System

With the decreasing of petroleum resource reserves and trend of crude oil getting moreobviously, oil purification requires a large amount of hydrogen source. So far, nearly70%ofit comes from hydrogen production device. In order to improve the yield of hydrogen source,it requires a large-scale unit. The most important part of large-scale hydrogen productiondevice is steam reformer, its working temperature is usually above820℃. In engineeringpractice, though, the furnace tube structure’s failure under the influence of creep deformationand thermal expansion, affecting the normal operation of reformer and reducing its workinglife. The thermal stress and creep analysis of the hydrogen production device tube system hasbecome a hot issue in engineering design, equipment operation and maintenance.This paper takes the material containing25Cr35NiNb as samples in the test of hightemperature creep mechanical properties. The experimental data and creep curves underdifferent conditions are obtained and then the constitutive equation of creep deformation canbe given. Theoretical method of the thermal stress and creep analysis in the hydrogenproduction device tube system is established using the thermal elastic-plastic incrementalmethod. By the10×104Nm3/h hydrogen production device tube structure geometry, the spacefinite element model is established using the pipe discrete element in ANSYS, Through thethermal stress and high-temperature creep analysis of the various components, The thermalstress calculation results and the stress and deformation of the various components after thefurnace tube creep1e5hours are obtained, and the strength was evaluated. According todifferent creep period of service condition in the past6years and the Larson Miller parametriccurve formula of materials, the calculation method of remaining life is established, and thefurnace tube has6.3years left. That provides a theoretical basis for the residual lifecalculation and the equipment operation and maintenance for this kind of device.