Challenge: Improve ROP and eliminate trips because of bit damage while drilling 12 1/4-in section through hard and abrasive siltstone intervals in Castilla field, Colombia.
Solution: Use a drill bit equipped with ONYX PDC cutters, which remain sharp longer than any other cutter.
Result: Saved two rig days while eliminating bit damage and setting a new ROP record for the Castilla field.
Ecopetrol, the National Oil Company, faces challenging intervals containing up to 70% hard and abrasive siltstone, with an unconfined compressive strength (UCS) up to 15,000 psi, while drilling the 12 1/4-in section in the Castilla field, Llanos basin, eastern Colombia. Aggressive cutting structures resulted in broken or chipped cutters, requiring extra trips to change the bit, while more durable drill bits reduced ROP. A solution was needed to improve drilling time.
12 1/4-in MDi519MHSPX drill bit equipped with ONYX PDC cutters was selected to drill Castilla 96 with PowerDrive vorteX powered rotary steerable system (RSS). ONYX cutters are more thermally stable, as well as more wearand impact-resistant than other PDC cutters, both standard and premium. The cutters remain sharp longer, translating into more footage drilled at maximum ROP over a wide range of applications. The cutting structure design is optimized for bit dynamics, formation lithology, and the entire BHA, using IDEAS integrated drillbit design platform.
The bit includes other features such as Lo-Vibe depth-of-cut control inserts, a short gauge length, and thermally stable polycrystalline diamond gauge protection to minimize vibration, improve steerability, and increase durability. The PowerDrive vorteX has additional torque capacity that allows a higher weight on bit for increased ROP and longer runs, and also reduces stick/slip and vibration. KLA-SHIELD enhanced-polymer water-based drilling fluid system, provided by M-I SWACO ensured optimum borehole conditions. Offset well data was analyzed in detail to select the most suitable operating parameters.
The bit drilled 6158 ft at 145.9 ft/h, setting an ROP record for the Castilla field and reaching its target depth 2 days ahead of schedule. Maximum deviation was 66°. The dull bit grading was 0-1-WT-S-X-I-NO-TD, confirming that the bit was in excellent condition with only slightly worn cutters on the shoulder.
Download: Two Rig Days Saved With Record ROP Through Hard and Abrasive Siltstone Layers, Castilla Field, Onshore Colombia (0.65 MB PDF)