基于蠕变损伤力学理论的HK40炉管焊接接头的蠕变损伤研究

1　前言熔焊技术的发明给制造业带来了革命性的变化 ,使得化工、石化以及发电等工业的大型高温过程装置得以建造。可是 ,在高温构件的失效中 ,焊缝的先行失效占有较大的比例 ,从而表明焊接对结构完整性的不利影响。为了实现高温构件的优化设计与维修 ,准确预测焊接构件的高温性能变得十分重要。转化炉炉管是高温下烃类转化制氢的关键部件。炉管材料一般采用离心铸造耐高温合金ＨＫ型( 0 4Ｃ ,2 5Ｃｒ,2 0Ｎｉ)或ＨＰ型 ( 0 4Ｃ ,2 5Ｃｒ,35Ｎｉ) ,整个炉管通常由 3～ 4根短管焊接而成。炉管在长期的高温服役过程中 ,材料微观组织劣化在晶…

Study on Creep Damage of Weldments of HK40 Furnace Tubes Based on Creep Damage Mechanics

The accurate prediction of damage behavior of welded components at high temperature is becoming incresasingly important in order to realize an optimised design and maintenance of a plant life.In the present paper,the creep properties of the weld of HK40 furnace tube are determined by means of a local deformation measuring technique.A damage mechanics approach is introduced to simulate the damage development and creep rupture of HK-40 furnace tubes due to the presence of a weld.Metallographical research also indicates that the weld has a higher damage rank.It has been illustrated that damage is prone to the weld in the later period of service life.It is thus concluded that the weldments may become the weak link in HK-40 furnace tubes.