The industry is finally on the verge of an intelligent completion. After 30 years of intermittent progress, the promise that we made to ourselves throughout most of our careers is nearing fruition. But now that it is here, it is rather different than we imagined. Rather than an intelligent completion, we have created an intelligent oilfield asset.
Rather than viewing completion technology as a whole, the industry has instead focused on parts of the system. Essentially what has been improved are downhole components that we called intelligent. The real challenge is to rethink what defines a completion. It’s far more than just a process that follows drilling. It is the mechanism by which an asset is produced for two or three decades. It is the single item that supports well revenue for life. To create an intelligent completion, we must think like our production teams and develop integrated intelligent systems that seamlessly spans from the drilling phase into production.
Early advances
In August 2014, a colleague shared a presentation entitled “What’s New in the World of Completion?” The main themes explored the rise of unconventional wells, sleeve developments, the daily new-and-improved composite plugs, and some interesting coil/frac applications.
By this time, intelligent components had reached maturity and their 20-year installation anniversary of the first intelligent well was near. All the majors had tested the intelligent-well technology. It grew steadily between inception and 2014, but how much the technology had advanced was debatable. The industry shuffled between controlling producers and controlling injectors, or both. Then we focused on ever-longer lateral sections with multiple zones or multiple reservoir-layers with the puzzling question of how many inlets to control. Then came highly deviated wells and then the effort to reduce the number of zones through hydraulic selector technologies.
In short, our activity and advancement track record through 2014 was one of chasing the latest shiny object. We failed to see the forest for the trees and apply these advances to completion.
Completion intelligence today
Today we have a strong case for electronic control. Having control using a single line or multiple lines in one bundle is appealing, as losing one valve does not mean you lose them all. Like many of our peer companies, Weatherford is developing electronically controlled completions technology. Ours will include technical features such as direct actuation to close position from any other sleeve flow setting, which is necessary for water injectors, but also move 90% of the electronic components to the surface to heed lessons from the past.
The true test of intelligence, however, is data. To gather downhole intelligence, we can instrument the well with either electronic or optical pressure and temperature gauges joined by a fiber-optic cable to enable DTS and DAS (distributed temperature and distributed acoustic sensing), in addition to well-contribution and flow-fraction measurement with downhole optical flowmeter. This intelligent system can command node points and optimize sleeve position by identifying the maximum production contribution zones.
More importantly, completion engineers focus beyond plumbing a well left by the drilling team; they seek production performance for the life of that well, which can potentially influence the placement, configuration, completion design and requirements of the next. We’re trending toward a symbiotic relationship between the driller, the completion engineer, and the production engineer.
Needs change, evolve
“There is nothing more important in petroleum engineering than a definite knowledge of the pressure at the bottom of an oil well at an existing operating condition, and the relation of this pressure to the pressure within the producing formation. A knowledge of the bottom hole pressure is fundamental in determining the most efficient methods of recovery and the most efficient lift procedures. Yet there is less information about these pressures than about any other part of the general problem of producing oil.”
Charles Millikan spoke these words in 1931. What was true then, remains true today.
Well instrumentation delivers reams of data the help us understand the downhole environment, but the challenge is doing something meaningful with it. To help meet this need, Weatherford introduced the ForeSite production optimization platform in 2017. This platform integrates reservoir data, downhole flow and production measurements, surface production data, production-optimization workflows, and even plant data into one ecosystem.
So rather than filing away disparate reams of data, we moved away from compiling reports to look for behavior anomalies, problems, and even opportunities to be a bit less conservative. One example could be to draw down a well beyond the practical rule without risk. Among other findings, we discovered that we can detect water breakthrough, coning, or interference from an adjacent injector earlier. We can detect anomalous flow, precursor of sand production, scale production, and screen plugging. We can detect water-hammer effects in injectors and cross flow in addition to interference and mapping pressure support mechanisms.
In short, we are learning to predict the future. This includes the impact on different phases of asset development, well placement, an evolved completion design or technique. We can identify—through managed pressure drilling and completions—future hazards like over- or under-pressured layers, fractures, and provide warning before it happens.
Looking to the future
Completion technology has moved on to remote operational tools, surface-controlled or remotely operated RFID, and other telemetry systems. Whether it is openhole over cased hole, step changes in equipment reliability, deeper wells, deeper waters, longer laterals—these all pose challenges that the industry must address.
It is perhaps outside the complex but narrowing completion discipline that we are seeing the greatest improvements. We are working with our drilling colleagues to deliver a better hole. We are instrumenting wells that provide information—and not just data—to better influence how that well and future wells are managed. We’re far more cognizant of the fact that those weeks or months of drilling and completing can and dictate how a well will produce for years into the future and how the asset must live with the consequences of decisions made during construction.
The author
Julio Bello is Global Product Line Manager, Reservoir Monitoring, Weatherford
