Designing and safely drilling offshore and deepwater wells requires a deep understanding of pore pressure, fracture gradient, and the often‑narrow window between the two. The benefit of drilling a hydraulically stable hole is great both in terms of safety and economics. Risks such as shallow‑flow hazards, kicks, losses, and borehole instability are therefore most critical in the deepwater domain. If not addressed, these hazards could lead to nonproductive time (NPT) in an environment where daily operational expenses often exceed $1,000,000.
Determining and navigating the safe operating window
Managing the relationship between hydraulics and borehole geology
Understanding and managing the causes of borehole instability
Reducing risk of stuck pipe and lost downhole tools
Monitoring key metrics to stay within safe operating parameters
After recognizing the challenges and risks of offshore and deepwater drilling, the critical task is how to avoid, manage, and/or mitigate them. The Drilling Advisor solution — which combines drilling optimization, wellbore stability, and drilling hazard management — offers a proven methodology that is effective in all types of fields.
By analyzing historical well data to identify drilling hazards and to build geomechanics and drilling‑optimization models, we create an enhanced drilling plan. Drilling within the appropriate margins (between the pore pressure, rock failure, and fracture gradient) helps to avoid kicks, losses, hole problems, and shallow‑flow hazards that are prevalent in deepwater operations.
During drilling, industry-leading Weatherford products—from logging-while-drilling (LWD) tools to the MicroFlux® managed pressure drilling (MPD) system — provide valuable downhole feedback that facilitates drilling hazard management analysis. Real-time monitoring through our Virtual Well Monitoring® service enables our team to identify deviations between models and actual drilling data. This comparison provides situational awareness of possible drilling hazards before they happen, and enables us to make appropriate adjustments as necessary to minimize NPT.
Finally, our knowledge management process captures the lessons learned in an end-of-well report that outlines key performance indicators (KPI), details opportunities for improvement, and makes recommendations for future projects.
Technology is at the heart of our approach to meeting clients’ needs. We constantly update and refine our technologies to solve new challenges encountered in the field.
The Microflux managed pressure drilling (MPD) control system enables real-time detection and control of minute downhole influxes and losses to minimize NPT spent managing well-control issues. This technology has been used extensively in deepwater fields, including the pre-salt fields of offshore Brazil and West Africa. MPD techniques can be incorporated into the well design to address downhole challenges beyond the capabilities of conventional technology, and to improve drilling efficiency and well integrity.
Reliable isolation in high-pressure, high-temperature wellbores
Deepwater wells require reliable liner systems capable of withstanding extreme pressures and temperatures. The SwageHammer system eliminates leak paths and other common points of failure to form a gas-tight seal for the life of the well.
The robust VariForm centralizer is able to withstand demanding run-in conditions and provides maximum standoff during cementing operations in a wide variety of wellbore profiles. It enhances the quality of the cement job and promotes life-of-well integrity.
Commonly, when drilling in deep water, there is a need to enlarge the hole beyond the previous casing diameter to run a subsequent string. In these cases, the RipTide reamer provides a flexible, efficient solution. RFID activation means that the reamer can be opened and closed multiple times and can ream different sections of the hole during a single trip.
The remotely‑operated LSS 1250 enables safe handling of heavy, deepwater landing strings from the driller’s cabin. In 2015, this tool enabled Weatherford to land a 1,180-ton (2,360,700-lb) casing string in the Gulf of Mexico — a world record. It is now rated to handle up to 1,500 tons.
The combination of our industry-leading technologies and our disciplined approach has produced measurable value for our clients.