Casing Wear Influence Factors and Range Analysis

Abstract

In the deep and ultra deep well casing wear is serious. The decrease of strength leads to casing damage, affects the follow-up well test and completion. In order to analyze the influence of the contact force, rotating speed, steel grade and muds on casing wear, determine the optimized level collocation scheme which makes casing wear minimum, optimize drilling parameters and casing programs, reduce casing wear, four factors and three levels orthogonal experiment of casing wear was carried out, and the range analysis of the experiment results is made. The results show that the best match of factors is A1B1C1D3, namely when the contact force is 200 N(A1), rotating speed 60 r/min (B1), steel grade N80(C1), oil-based mud (D3) casing wear is minimal. The influence of muds on casing wear is the largest, the next is casing steel grade, and then rotating speed, the effect of the contact force minimal. The improvement of mud performance is best method to reduce casing wear.