Customer Challenges
- A long-term client was required to drill a challenging 16-in section from 1,321 m to 3,005 m MD, covering 1,684 m with an inclination increasing from 72° to approximately 80°
- The extended high-angle profile, combined with a large annular clearance between the drill pipe and 16-in hole / 18-5/8-in casing, created a significant risk of cuttings bed formation and poor hole cleaning. Hydraulic performance was further constrained by flow-rate limitations, reducing the ability to transport cuttings effectively through hydraulics alone
- These conditions increased the risk of:
- Cuttings accumulation and poor hole condition
- Elevated ECD
- Increased torque and drag
- Pack-off and stuck-pipe incidents
- Wellbore instability
- Difficult tripping and casing running operations
- The operator required a reliable solution that would support hole cleaning throughout the section and help ensure efficient, uninterrupted drilling to TD
Expro Excellence
- After reviewing the well design and operational challenges, Expro proposed the deployment of 5.5-in CBI™ (Cuttings Bed Impeller) tools to supplement hydraulic hole cleaning with mechanical cuttings-bed agitation
- CBIs were strategically placed throughout the drill string, with one tool per two stands in designated intervals, targeting the critical large-annulus environment inside the 18-5/8-in casing
- Expro worked closely with the drilling team to optimize hole cleaning performance through:
- Mechanical agitation and mobilisation of cuttings beds
- Continuous monitoring of flow rate, ROP, torque, annular pressure, and ECD
- Drilling parameter optimisation through changing formations
- Hole-conditioning and circulation cycles as required
- Full hole-cleaning circulation before trips and at TD
- This integrated approach helped maintain effective cuttings transport while managing increasing torque, high cuttings volumes and ECD limitations throughout the section
Value to Client
- The combination of CBI™ technology and proactive hole cleaning management delivered a successful outcome:
- Successfully drilled the entire 1,684 m high angle section to TD
- Reached planned inclinations of 79-80°
- Maintained stable drilling performance with:
- Approximately 5,000 lpm flow rate
- 18-23 m/hr ROP
- Around 160 rpm rotary speed
- Stable hole-cleaning performance observed throughout the interval
- Effective cuttings removal demonstrated through improved shaker returns and controlled ECD trends
- No significant drilling interruptions related to cuttings loading or poor hole cleaning
- Hole circulated clean at TD, enabling a successful POOH with only minor localized overpull
Contact
For further information, please contact coretrax@expro.com.
