Large Size Nonstandard Liner Cementing Technique in Yuanba Gas Field

In order to solve the difficulties of running casings safely and increasing the cement quality of liners in Yuanba Gas Field,on the basis of analyzing the factors affecting the cementing quality,the parameters of hanger are confirmed by casing weight and flow area;the performances of cement slurry and ahead fluid are optimized to satisfy the requirements of preventing gas breakthrough in cementing and increase the cementing quality.Besides,the borehole preparation is strengthened,including running gauge cutter,pressuring and cleaning well.In order to improve the efficiency of displacing,the specific string structure and the technologic measures for cementing are designed.Consequently,the qualification rate rises to 100% and the high quality rate reaches 54.5%.The technology has successfully solved the difficulties of cementing technology from continental facies in Yuanba Gas Field.