Research and Application of a ϕ273.1 mm Infinite Circulation Liner Hanger in Yuanba Gas Field

Technical problems were encountered when cementing ϕ273.1 mm liners in Yuanba Gas Field, such as long open holes and liner sections and small annular gaps, further leading to difficulties in running the liner to the targeted area and measuring slurry displacement, as well as impeding the midway pump start-up. Considering geological conditions, borehole conditions, tool functions, etc., a infinite circulation liner hanger, integrating a pressure balance mechanism and embedded slips, was adopted and combined with a supporting rubber plug system. Moreover, specific measures for running the liner were introduced. Implementing the technique in 7 wells of Yuanba Gas Field eliminated the midway circular resistance and allowed liner running into the targeted area safely with a successful rate of 100%. The compound signal of rubber plugs was evident, and slurry replacement was accurate, with a bump rate of 85%. The results confirmed the remarkable performance of the infinite circulation liner hanger in cementing the ϕ273.1 mm liner in Yuanba Gas Field. This liner hanger is worthy of popularizing, for it has provided an effective way for cementing large liners with long open holes in Yuanba Gas Field.