Analysis of the capability of casing tripping in horizontal well

The emergence of horizontal wells brought new vigor to the oil and gas exploration. However, the casing is bended with the hole at the curved portion in horizontal wells, which makes running casing more difficult, because the resistance is larger in horizontal wells than that in vertical ones. Whether the casing strings can run in the bending of horizontal wells relates to the completion style, which can be judged according to casing force analysis. Through the force analysis of casing string units in two and three dimensions wellbores, we get the generic algorithm to calculate the axial loading of directional wells. The algorithm is applicable to calculate the axial loading of all types of casing strings. The accurate analysis of frictional resistance can provide a reliable basis for the drilling equipment selection, optimizing the parameters of casing strings, and choosing the way to trip in.