The drilling activity challenges in Azerbaijan are usually associated with the Pereriv (also known as the Fasila) formation due to highly abrasive tight sandstones and high vibrations while drilling, especially in deeper zones. Optimizing the rate of penetration (ROP) while maintaining toolface control is a challenge in the region when trying to reduce cost and maximize margins for customers. One past solution included a choice of premium milled-tooth roller-cone bits with multiple trips due to the bearing and seal life of the cones. Polycrystalline diamond compact (PDC) bits were another solution that yielded marginal ROP improvement when not sliding and balling issues were not present. After a nearly year-long preplanning phase, the customer drilled these formations with a hybrid drill bit and tripled the previous ROP without any noticeable drop entering Fasila. Throughout the section the weight on bit (WOB) was limited due to very high cuttings volume from the increased ROP. Overall, the first hybrid bit run replaced two roller-cone bits, and the second deeper hybrid bit run replaced 2-½ roller-cone bits. Sliding was deployed during drilling with no issues, maintaining toolface control. Hole quality improvements were noted during successful wiper trips and casing.

Even though hybrid bits were previously used in the Caspian Sea region (Kazakhstan side), the two included case studies represent the first experience of hybrid bit technology used in Azerbaijan accounting for multiple achievements and potential break-through performance for future projects.

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