Research On Decarburization Layer’s Thickness Of Heavy Rail Of Baogang Rail And Beam Factory

In recent years, due to the importance of the railway and the rapid development ofhigh-speed railway, people has higher and higher requirements for the quality ofhigh-speed steel rail, so the inevitable defects of the rail during the heating process becomethe focus of research. The decarburization of high-speed steel rail is one of the maindefects of the rail surface quality, which led to the decreasing of the mechanical propertiesof heavy rail directly, reduce the hardness and fatigue strength, and wear someshortcomings, affect the qualified rates of the product.On the basis of the actual situation of Baotou Rail Beam Factory, in which organizedecarburization layer experiment, this topic combine the theory with practice, statistic thedata, analyze and study the influencing factors and relations with high-speed steel raildecarburization. Main purpose is to decrease the thickness of the decarburization layer ofhigh-speed steel rail in the practical production, to improve product quality and marketcompetitiveness.Research method is given priority by statistics, during the production, organize thedecarburization layer experiment, check the formulation sample of rail quality inspectionwith microscope, sampling, statistical experimental results and the field related monitoringdata, analyze the relationship between different factors and decarburization high speed rail,and get the actual operational method that decrease the thickness of the decarburizationlayer, optimizing burning steel.In order to study the high speed rail decarburization layer condition comprehensivelyand seriously, organize experiment from four aspects:1) Steel and Decarburization layer,the statistic and study experimental condition of four different steel high-speed steel raildecarburization layer U71Mn, U75V, U76CrRe and KB1250respectively, get theeasy-controlled decarburization layer steel in order: KB1250-U76CrRe-U71Mn and U75V;2) heating time and the decarburization layer: select the billet steel in high temperatureperiod of different time of the experimental sample as the research object, concluded that the steel billets in the heating section of average temperature is1250℃environment for30minutes, the decarburization layer thickness will be0.4mm or more, and volatility islarger, it is not easy to control;3) heating temperature and decarburization layer: using twokinds of methods that are gradient burning steel and the melt temperature-decreasingmethod, research reasonable distribution of furnace temperature progressively, the melttemperature of steel billet control in the range1080~1100℃, can effectively reduce thethickness of the decarburization layer high-speed steel rail;4) Furnace atmosphere (process)and decarburization layer: use strong oxidizing atmosphere and weak reducibility toburning steel, get the weak reducibility atmosphere, can prevent the decarburizationhigh-speed steel rail effectively. Finally, by synthesizing all kinds of methods on decreasethe thickness of the decarburization layer about various of influence factors, combinedwith the actual operability, concludes that high-speed rail against the decarburizationheating system, with optimizing the heating process.The study results provide the practical parameters for the high-speed steel raildecarburization theory, provide the effective measures and methods fordecarburization-control during the production, improve and optimize the heating process, ithas practical guiding significance for iron and steel enterprise.