Study On Degradation Of Cr9Mo Furnace Tube Material

Through failure analysis, to determine the maintenance interval of good technical foundation, also can improve the efficiency of resource use, as far as possible to achieve reasonable economic use of furnace tube, solid the overall goal of production safety. Forecast the life of the equipment mainly comes from the study of workblanks equipment problems. Furnace tube as a key part of the heating furnace, faced with the harsh working environment, under the action of high temperature and high pressure and complicated medium, furnace tube material performance gradually decline and deterioration, will lead to the furnace tube gradually shorten the service life. In the heating furnace tube in the process of service, the main failure forms including carburizing, carburizing cracking and creep cracking.In this paper, combining with the reforming furnace tube heating furnace of Sinopec Luoyang and its material to carry out comprehensive degenerative and performance testing, master furnace tube material by the current deterioration and damage degree, can carry on the reasonable forecast of its residual life, and then make a conform to the enterprise development goals and economic interests of operation strategy, maintenance and daily maintenance and replacement if necessary. The study of the paper provide a basis for the test and operation in the above measures.By studying the paper’s main conclusions include the following aspects:Firstly, in the internal and external surface of the furnace tube, after analysis, there is no significant corrosion pits and similar defects. In the walls of the furnace tube, under the influence of high temperature and high pressure, the oxide layer of dense, significantly. Including welding joint section of slight deformation phenomenon.Secondly, Cr9 Mo of furnace tube, after many years the operation of the high temperature condition, the more severe high temperature creep phenomenon. The carbide quantity, wide range of creep cavity, some crack problem.Thirdly, Cr9 M after years of complex medium of high temperature and high pressure conditions of service, the strength of the furnace tube material appear obvious drop, compared with the weld material has strong shock resistance.Finally, for predicting the service life of furnace tube, considering the stress of furnace tube, as a component of low stress stress is not the furnace tube damage and destruction of the key factors, so you can think the residual life of furnace tube is about 4 years.