Auxiliary technology of drilling speed improving for Well Keshen-206 with high and steep structures

Well Keshen-206 in Kelasu tectonic zone is a fifth spud production evaluation well. The well faces large dip angle and easy inclination in upper formation, low ROP of Jidike gravel formation, easy pipe stucking of Paleogene Kumugeliemu group salt layer, low ROP of Cretaceous Bashijiqike formation, narrow pressure window, wellbore instability, easy leakage and other drilling difficulties. In view of the difficulties above, through the use of PDC bit optimization technology, vertical well drilling technology, and salt layer drilling fluid system optimization, the drilling speed of Well Keshen 206 is improved significantly. The drilling cycle is 250 days and 11 hours, being shortened by 47.5%, compared with the same block drilling cycle. The technique provides a valuable experience for future drilling operation in Keshen 1-2 deep tectonic.