Automated Operations and Wired Drillpipe Benefit Arctic Drilling
You have access to this full article to experience the outstanding content available to SPE members and JPT subscribers.
This paper presents a case history of drilling automation system pilot deployment, including the use of wired drillpipe, on an Arctic drilling operation. Two major aspects of technology were introduced during this pilot, the first being a drilling automation software platform that allowed secure access to the rig’s drilling control system. The second component was a wired drillstring, which provides high-speed delivery of downhole data from a series of distributed downhole sensors.
In an effort to enhance the safety of its operations, improve well construction efficiency, and leverage the potential opportunities presented by digitalization of drilling, the operator has initiated a Remote Operations and Intelligent Automation Project. The project involved the deployment of an automation operating system (AOS) on top of an existing drilling control system. The AOS provides the ability for secure, programmatic control of the rig’s major drilling hardware through the use of software. The software interface allows for custom configuration of several routine drilling activities for automated execution.
The project also evaluated the latest version of the service company’s wired drillpipe (WDP). At the time of writing, the project has delivered eight wells, with various combinations of the technology implemented.
The overall objectives of the project were to evaluate
- The readiness of the AOS for wider deployment
- The reliability of the latest version of WDP
- The maturity of the AOS drilling applications
- The effectiveness of this technology in reducing well costs
For each well, key performance indicators (KPIs) were defined that aligned with the project-level KPIs and are dependent on the specific aspect of the technology being used on that well.
The giant Prudhoe Bay field, on the North Slope of Alaska on the edge of the Arctic Circle, was discovered in 1968 with an initial estimate of 22 billion to 25 billion bbl of oil in place and has been in production since June 1977. Since the field began production, it has generated more than 12.5 billion bbl of oil, making it the most productive US oil field. The field has been a proving ground for advanced drilling techniques, including multilateral and coiled tubing, now used in oil fields around the globe. Production from Prudhoe Bay is supported by ongoing drilling activity.
An overview of the automation technology is presented in Fig. 1.
AOS. The AOS is a process-control-software layer installed on an alternating-current electrical drilling rig (with the requisite hardware and baseline drilling control system) and enables automated drilling control. The intent of this software is to deliver routine processes better, such as ramping up pumps, tagging bottom, and optimizing parameters while drilling. This will enable the driller to focus on safety and operationally critical processes, including crew-resource management. These tasks require an in-depth knowledge of the operational context, informed largely by data that are not captured digitally, which an experienced and informed driller is more adept at managing than an AOS.
The AOS consists of several single-board computers installed in the controller cabinet, an additional or supplemented screen, and an interface switch, with the latter two in the driller’s cabin. The system has an initial installed configuration that defines how the AOS will perform certain tasks such as pump ramp speeds and block acceleration while transiting back to bottom.
Configuration options are extensive and allow for high levels of customization. Configuration, however, is not isolated to installation, and the AOS interface allows for on-the-fly changes to the system setup, allowing for active optimization management as conditions change.
Integral to the AOS system is the well program. This allows the drilling engineers to provide the AOS with sets of operating-parameter envelopes [e.g., weight on bit (WOB), rotational speed, torque, flow, pressure, rate of penetration (ROP)] that define how the well should be delivered by the system. These can be specified for a desired interval and are digitally uploaded into the system. Crucially, the driller does not have access to edit these parameters while operating within the AOS, so any change required must go through a defined escalation and review protocol.
WDP. A new version of WDP was commercialized in 2016 and reported by the supplier to have improved overall system reliability significantly. Additionally, with the introduction of the AOS and the ability to use high-speed data to drive drilling-parameter optimization and control, the operator decided to use the second version of the WDP as a component of the automation project.
In addition to re-engineering of the coil placement, the system included some ruggedization of components such as data links (booster subs). The design also focused on lowering cost of maintenance by considering the induction coils as a consumable that could be replaced.
Two different applications for automated ROP optimization were also part of the project delivery. The first was based on control of downhole WOB (DWOB), and the second was based on the use of a searching algorithm.
DWOB Control Application. The DWOB controller is a real-time supervisory control application installed on the AOS that delivers a set DWOB value desired by the driller.
The application acquires high-speed data from both surface and downhole sources. These data are then statistically analyzed. A complex computation is then performed to create a surface WOB (SWOB) setpoint for the AOS to use and to deliver the DWOB required by the driller. The AOS and autodriller receive the setpoint and apply a contextual test of operational state to determine whether to apply the required setpoint.
ROP Optimization Application. The drilling-parameter-optimization application functions in two primary modes: surface and downhole. Each mode uses a subtly different logic or algorithm. In surface mode, the application acquires surface data from rig sensors and applies a Gaussian logic and simple cost function with variable weighting depending on the performance criteria required. For surface optimization, the cost function is weighted between ROP and mechanical specific energy (MSE). Once the application is engaged, the system begins an automated drilloff test to find the optimal parameter set to deliver either the maximum ROP or the minimum MSE.
In downhole mode, the application is able to integrate downhole lateral and torsional vibration data from the WDP network. As with the surface optimization, the application uses Gaussian logic to create a synthetic 3D topographic map of performance vs. drilling dysfunction, with performance being the third dimension. Cost-function weighting in this mode also considers vibration levels.
AOS and WDP Applications
The AOS and WDP technologies deliver distinct but complementary functionality. The AOS was focused on the delivery of the following capabilities:
- Automated connection sequences
- Closed-loop-drilling-parameter management
The WDP was focused on the delivery of the following capabilities:
- High-speed telemetry
- Closed-loop-drilling-parameter management
- Distributed (or along-string) sensors
The complete paper presents the application and results of the implementation of these capabilities in the first eight wells of the project.
Preplanning. The experience of delivering this project to one of the more remote operating fields in the world has highlighted several areas that are critical to the success of the overall project. Perhaps the most obvious, but one of the more challenging, is to achieve the right levels of engagement and alignment from all parties involved, including the operator’s teams, rig contractor, third-party drilling services, and the AOS/WDP supplier. Without this engagement and alignment in place, some of the more tactical challenges around identifying and prioritizing bottomhole-assembly components for wire, agreeing on KPIs, aggregating data, distributing and archiving plans, adapting well designs, modifying work flows, evaluating subsurface and nonstandard drilling opportunities, and ranking problems during operations all become exponentially more difficult. Another important aspect of the preplanning stage is to consider the effect of contingency scenarios and how or if the AOS/WDP operations may affect these.
Operational. Once the project was kicked off, one of the more-valuable resources introduced was the role of project coach, an employee from the operator whose role was to support the teams on a daily basis. This support came in many forms, the most important of which was to ensure that the right balance was achieved in delivering the technology evaluation with minimal disruption to the operations and, conversely, to work with the operations team to ensure that the objectives of the trial remained in focus and were able to be executed.
Technical. On the basis of analysis of some of the data presented earlier, the operator has recognized the benefits of automation as an opportunity to bring increased procedural discipline in executing aspects of well construction. Perhaps the best example of this was on the second well of the campaign, where a serious downhole issue during the drilling of the 6⅛-in. production hole required a significantly more complex procedure for the connections to be implemented. This process was configured into the AOS for execution, and, after a couple of interventions for optimization, every connection was delivered as required, with minimal variation between connections. The capabilities demonstrated by the AOS to execute the same task repeatedly bode well for its implementation in challenging offshore wells, where this ability to be more systematic in executing procedures holds significant benefits.
For a limited time, the complete paper SPE 191574 is free to SPE members.
Automated Operations and Wired Drillpipe Benefit Arctic Drilling
01 February 2019
Equinor, Transocean Ink Deal for Five Automated Rigs
The contract is helping to solidify Europe’s offshore sector as the focal point for the rise of automated drilling technology.
Automated Real-Time Torque-and-Drag Analysis Improves Drilling Performance
In this paper, the application of a real-time T&D model is demonstrated. The process of T&D analysis was automated, and the time and cost required to run physical models offline was reduced or, in some cases, eliminated.
Automation-Adoption Approach Maps Human/System Interaction
This paper describes the progress of directional-drilling-automation systems along the cognitive functions and levels of automation as defined by the Levels of Automation Taxonomy (LOAT) hierarchy introduced by the Drilling Systems Automation Roadmap Industry Initiative.
Don't miss out on the latest technology delivered to your email weekly. Sign up for the JPT newsletter. If you are not logged in, you will receive a confirmation email that you will need to click on to confirm you want to receive the newsletter.
12 February 2019
05 February 2019
06 February 2019
08 February 2019