Developing new fields can require multiple wells, drilled with a factory-like cadence. As the frequency of wells drilled increases, the value of accurate bit selection becomes more apparent, and the results of simply running an off-the-shelf product can limit the ability to increase well count.

Halliburton’s Drill Bits and Services product service line leverages a global network of drill bit designers, differentiated by the Design at the Customer Interface (DatCI) service. The company’s Application Design Evaluation (ADE) service specialists are focused on local solutions; there is no global triage list that often can provide important operations with a generic solution. The DatCI service provides the framework for a solution that is focused on driving efficiencies into operations by solving specific bit-related drilling issues.

The Drill Bits and Services arm has approximately 50 ADE service specialists deployed in operations around the world. The service specialists deliver a local solution developed collaboratively with its customers through proprietary DatCI methodology, which provides the foundation for iterative performance improvements.

Working at the local level allows designers to understand the drilling challenges in a specific field and to physically inspect bits post-run to identify opportunities for improvement, leading to higher ROPs and longer run lengths. (Image courtesy of Halliburton)

These solutions incorporate many tools, including iBits design software, Direction by Design software (DxD), and computational fluid dynamics coupled with a global library of performance data and SPARTA modeling software for geomechanical analysis. The coupling of iBits with DxD software’s ability to model the directional forces required to steer a bit allows designers to create a cutting structure that is durable enough to handle tough transition drilling while maintaining directional control.

The key element in the DatCI process is the service specialist’s ability to leverage the tools and to quickly develop design iterations that improve upon the previous design. Working at the local level allows designers to understand drilling challenges in a field as well as physically inspect bits post-run to identify opportunities for improvement, leading to higher ROPs and longer run lengths. ADE service specialists also are linked into the global network, allowing them to learn from one another and resulting in a faster learning cycle. The end result of the DatCI process is a predictable, accurate, and repeatable solution.

Ecuador case history
Working with an operator in the Indillana field in Ecuador, the challenge was to drill the 12 1/ 4 -in. section in one run, eliminating two bit runs from the current drilling curve. This interval comprises two distinct sections, including an upper section that previously used two bits due to the presence of chert in the base of the Tiyuyacu formation. The hardness and abrasiveness of chert often required the frequent use of an insert roller cone bit. The bottom section presented two distinct challenges. The first 800 ft (244 m) was composed of plastic shales (Tena formation) that caused bit balling and resulted in low ROP; the second challenge was an interval composed of shale and limestone with high compressive strength and abrasive sandstone stringers (Napo formation) that produced high wear on the bit, leading to costly bit trips.

The drilling challenge was to drill the entire interval in a single run with a fixed cutter bit with a higher ROP and a better dull grade condition than the current solution, eliminating bit trips and reducing nonproductive time (NPT). The wells to be drilled were directional with a “J” profile, dropping at 1 degree/100 ft (1 degree/30.5 m). The 12 1/ 4 -in. section was to be drilled with a fixed cutter bit through the Tena and Napo formations.

After evaluating formation strengths, drilling parameters, directional profiles, and the dull grading of previous designs, the local ADE service specialists determined the application was PDC-drillable with FX Series drill bit technology. A five-bladed FX56D bit was designed with an aggressive dual-row cutting structure featuring 19-mm XSeries cutter technology. The dual-row cutter technology incorporates force management and drilling dynamics optimization to deliver high ROPs without compromising bit life. The dual-row cutting structure reinforces the nose, shoulder, and gage and engages when primary cutters become worn or damaged. The XSeries cutter technology optimizes abrasion and impact resistance and has greater thermal stability to withstand the friction head generated during drilling.

In the first well, the FX56D bit drilled 1,351 ft (412 m) in the 12 1/ 4 -in. section at 58 ft/hr (17.8 m/hr); in the second test well, it drilled 1,501 ft (457.5 m) at 56 ft/hr (17 m/hr). These runs beat the field average for the interval by more than 28 hours and beat the field record by more than 25 hours, resulting in a savings of more than US $145,000 per interval.

This solution was the result of Halliburton’s local expert working collaboratively with the customer, focusing on specific drilling challenges. Due to the ADE service specialists’ work, shoe-to-shoe drilling in a difficult multiformation interval now is possible. The customized solution reduces NPT and continues to push performance boundaries within the field.

The DatCI process now will be used in developing a subsequent solution that will continue to reduce drilling time. Success required a customized solution.