Drilling advances

Defining what makes for a better well can be as challenging as trying to convince a New Yorker that having a frac spread in his or her backyard enhances the neighborhood ambience. 

The blueprint has changed. Whereas once the objective of a drilling program was simply to turn a useable borehole over to the completion team, well designers these days often must take into account the usability of a wellbore, even after the eventual abandonment. Contemporary well construction programs have taken on a new dimension with hydrocarbon-depleted wells frequently repurposed as carbon storage vessels and other post-production applications.        

"What is a better well is not an easy task to define," consultant John de Wardt said, in joining an eclectic group that set out to do just that during an IADC Drilling Engineering Committee (DEC) hybrid technical forum on Sept. 19. Presentations focused on both land and deepwater, with the ubiquitous focus on digitalization.    

Realigning objectives. At its core, a better well is one delivering higher net present value (NPV) during its productive lifetime. But getting to that point is where the challenges lie. After giving a tutorial-of-sorts on the Capex and Opex relationship to higher NPV, de Wardt pointed out the importance of well designs that consider drilling, completion and production peculiarities. "Wells are designed from the bottom up, so drilling has to take into account the completions and the completions have to take into account production," he said.  

He emphasized that Capex, for instance, should include total well costs, unlike the typical North American scenario, where drilling and completions are budgeted separately, with disparate economic and operational objectives. As a case-in-point, he said an operator, which upon investigating a decline in frac efficiency across an asset, found drillers were using wellbore strengthening material to help drill wells more easily, but that same technique was preventing fracs from forming properly. "So, again there's a direct correspondence between the drilling process and the completions process," he said.   

Oftentimes, a better well results when all parties are consulting and operating on the same page, as reflected in a well offshore West Africa that had been producing 2,000 bopd from a roughly 3,281-ft lateral section. "We actually got the subsurface, completions and drilling teams together and built a new (reservoir) drill-in process, and then a process for cleaning up the completions, and production went to 3,000 bopd with very little investment," he said.   

Expanding the digital footprint. Notable advances aside, "digital technology today is not being fully leveraged by the industry," which often overlooks current software technology stacks and off-the shelf software products.  

So says Khaydar Valiullin, founder of the WellsX Eco automation platform, described as using "multi-physics modeling engineering expertise to enable more robust modeling via a digital twin, continuously calibrated to evolving conditions."  Incorporating a cloud-based multi-rig data repository with process control automated decision-making and reporting and real-time key performance indicators (KPI) calculations and visualization, Valiullin said the Eco system has reduced well construction time and costs in both exploration projects and brownfield developments.   

Valiullin cited an operator drilling wildcats in hard-to-access locations in Eastern Siberia, which after employing the Eco platform and its dynamic digital twin component, saw average well construction time drop from 159 days to 101 days, with an 80% reduction in flat operations time.    

The platform also was deployed on more than 25 production wells drilled for a European operator on mature fields, with a well-defined subsurface play model, and it reduced average well construction time 30%, with a 44% drop in non-productive time (NPT).   

A subsequent presentation examined a recent initiative orchestrated by Canada-based Ensign Energy Services that incorporates an Excel template to standardize the drilling programs that operators provide contractors. The eyebrow-raising STUPID, or Stop Typing Unnecessary Program Information Details, project replaces the time-consuming and error-prone manual entry of drilling programs.  

The two-part initiative comprises the development of the data categories, naming conventions and the data structures for the transfer and conversion of digital drilling programs from a standardized Excel spreadsheet to an easy-to use JSON (JavaScript Object Notation) text file. The second phase will feature a trial run incorporating some sort of data transfer protocol with one or more operators, according to a post by VP Mark Anderson.  

Ensign Drilling Solutions intern Nicholas Brown, a University of Wyoming PhD student and one of the architects of the STUPID initiative, told the forum that standardizing the exchange of well planning data "creates less confusion between companies, increases efficiency between companies, and ultimately leads to reduced costs and time commitment."   

He said Ensign is offering a “gentleman's agreement" for any company wanting to participate in the initiative.   

Staying on target. Improving the processes means little if you're continuously missing the pay zone. “How many times have you woken up to a target change overnight, and everyone is scrambling to figure out what happened," asks Kyle Underwood, a technical sales representative for Helmerich & Payne. 

He says automated geosteering, which offers a combined view of drilling and geology, helps eliminate wrong turns by letting the drillers know early on that they are in the center of the targeted zone, thereby avoiding unnecessary slides. "Of course, if they miss this detail and decide to plan for a slide anyway, the geologists get an early slide warning and can make a preemptive target change, letting the driller know there’s no need to slide," he said.  

Adding to the unpredictable nature of geology, longer laterals and tighter drilling windows magnify the human variability that often leads to inconsistencies. "Automated geosteering is designed to help navigate your well with a combined view of drilling and geology, so you can reconcile uncertainty for accurate placement in the pay zone," he said.  

Turning to deep water, Steve Rosenberg, executive VP and chief technology officer for Subsea Drive Corp., Cypress, Texas, made the case for casing drilling as a replacement for jettison drilling, typically used to deepen the initial structural casing depth, based on the prevailing fracture gradient. 

"Casing drilling is a more mechanically efficient process than jetting, as it uses casing rotation and optimal hydraulics to drill and is not limited by a mud motor, as used in jetting," he said. "Casing drilling is well-proven in land and shelf operations for top hole drilling efficiency, flat time reduction, mitigation of hazard intervals in a single trip, with the ability to cement upon reaching TD." 

Unlike jetting, he said riserless casing drilling also widens the deepwater drilling window and enables larger tubing and higher reservoir inflow and production rates.  

About the Authors

Jim Redden

Contributing Editor

Jim Redden is a Houston-based consultant and a journalism graduate of Marshall University, has more than 40 years of experience as a writer, editor and corporate communicator, primarily on the upstream oil and gas industry.