DEEP-WELL LINER CEMENTING TECHNOLOGY IN WELL YUNAN 21

The well Yun'an 21 is a development well in HongJiawan buried structure.The design well depth is 5709m.The well depth increased and open-hole section length increased to 1800m because met fault formation in practical drilling process.The cementing of this well belongs to liner cementing of low-pressure leakage?over-length cementing point and small interval.The paper introduces the difficulty,measures and field application of the cementing technology in the well Yun'an 21,as well as the optimization selection of cement slurry system.