Abstract:The relationships between changes of constitute of straight-run distillation diesel,catalytic diesel oil and hydrogenation refining diesel oil with the lubricity were investigated.The corresponding relationships between distillation range,90% distillate temperature and its lubricity of diesel oil were observed.The results show that the lubrication performance of catalytic diesel oil is the best,and then is that of the straight-run distillation.As for the hydrogenation diesel oil,along with the depth of hydrogenation increased,the diesel oil anti-wear performance is getting poor.The components which improved the lubricity of diesel oil are more concentrated in the high distillation range.90% diesel distillate temperature has a rather good linear correlation with diesel lubricity.The effective anti-wear components of diesel oil are often concentrated in the heavy components,and with the heavy components content increased,the anti-wear performance of diesel oil is getting better.