双心钻头在塔里木地区的应用

塔里木盆地地质情况复杂、井深,有许多钻井技术难题。下第三系的复合盐岩层分布广、埋藏深,用双心钻头钻进可有效地推迟或消除地层塑性蠕变而造成的卡钻;取心井段用双心钻头扩眼,可提高再取心时的岩心收获率;加深井钻进,用双心钻头可增大环空间隙,提高固井质量。"九五"期间塔里木深井、起深井增多,双心钻头在深井、超深井复杂井段和小井眼扩眼段有广阔的推广前景。

APPLICATION OF DOUBLE CIRCULAR BIT IN TARIM REGION

There are very complicated underground geological conditions there in Tarim Basin and wells there are usually with great depth and lots of downhole troubles. Varlous rock salt layers are broadly distributed and exist even in deep intervals. Drilling with double circular bit can effectively reduce or eliminate creep of plastic formations and therefore prevent pipe sticking. Higher core recovery is assisted in coring operations when this kind of bit is used for hole enlargement. Prolonged drilling of completed wells can extent the annulus of the hole and enhance cementing quality. Application of double circular bit will open a prosperous future in Tarim Basin for drilling deep, extra-deep, slim wells and wells with downhole problems in the period of the 9th 5 year plan of national economy.