Abstract: The article makes a hydraulical and thermadynamical analysis of mechanism of blending crude oil in pipelines, ohtaining a few methods for intensified blending: using small size pipeline to extend the length of blending pipelines; making the inner wall toughter; speeding up the flow of liquid in pipelines. It is proved through practice that, blending crude oil in pipelines, because of being done in a closed way, thus avoids contact with outside water and other inpurities so as to lessen the oxidation of oil products, make them evenly blended with additives and garantee the correct rate at one time. The quantity of additives is thus dramatically reduced and so is the production cost. Therefore, it is verified that blending crude oil in pipelines is not only feasible, but economical and simple as well, Also touched in the article are briefs of the meters used for it.