REAMING TECHNOLOGY IN THE LONG OPEN HOLE OF THE DEEP WELLS IN TARIM

Due to the complicated geological conditions in Tarim Oilfield, non conventional casing programs are applied for some complex wells, for safe drilling into the target zones. However, suitable matching drilling techniques must be available, e.g., to run the ?193.7mm non-joint casing to the designed depth, reaming is required in the ?215.9mm hole. For example, in Well Tacan-1, hydraulic reamer was used in the ?215.9mm hole, and the ?193.7mm non-joint casing was successfully run to 693.24m, with a string length of 1651.24m; by using the eccentric bit in Well Qiucan-1, the ?193.7mm non-joint casing was smoothly run to 6271m, with a string length of 2800m. Both the two reaming methods all obtained good results, and the operation characteristics and key points in this technology were stressed in detail.