INNOVATIONS AT THE WELL SITE/
Automation Driving Ability to Fracture Rock By Tim Marvel, SEF Energy
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owning, a leading technology provider, has developed an automated system that methodically eliminates the time between plug-and-perf stages with the goal of fracturing the reservoice 24 hours a day, seven days a week. The ability to fracture a reservoir 24/7 is a monumental improvement over having to be on a frac site 24/7, which occurs today. Plug-and-perf stages start with pumping down a bridge plug on wireline with perforating guns to a given horizontal location near the toe of the well. Once the plug is set, the zone is perforated. The tools are then removed from the well, and the fracture stimulation treatment is pumped in. In the implementation of an automation system, the primary barriers to fracturing the reservoir 24/7 are: 1. The time between stages (this includes transition time and pressure tests) 2. Downtime associated with gate valve maintenance and failures 3. Pump maintenance Following an automation roadmap similar to those utilized for autonomous driving, Downing has automated multiple sub-systems over the past four years and integrated these sub-systems into a comprehensive automated surface system. The elimination of these barriers provides wide-ranging benefits including 24/7 fracturing, cost reduction, safer operations, increased frac fleet utilization, logistical support and completion design flexibility.
hydraulics introduced at Level 1. Level 2 adds functional automation, such as hydraulic latches or greasing manifolds. These functions are tied together into sub-systems in Level 3 as seen in automated frac valve, automated latch and automated zipper control. Level 4 automation digitally ties these surface sub-systems together enabling the sub-systems to work together without human intervention. The roadmap culminates with a closed loop, Level 5 system that ties together the three primary frac systems: pump, wireline and surface systems. These systems function without human intervention, operating from stage-to-stage without human input except when required to stop the process for resupply or maintenance.
Current State of Plug-and-Perf Completions
Most plug and perf completions today employ Level 1 or Level 2 automation, which are relatively manual-operated process levels. At these current levels, hydraulic valve actuation is completed with levers, greasing is done manually, and wireline is attached via a latch. Few, if any of these sub-systems are integrated, requiring human intervention using manual checklists to ensure proper function and sequencing. Functional time tracking is generally handled via spreadsheets with the start and stop time at the discretion of a company representative, leading to inaccuracies and inconsistency between frac jobs. Without consistent time stamping via automated algorithms, assessing the performance of one frac job versus another, as well as identifying improvement opportunities, is exceedingly difficult.
Why Automation?
Utilizing the roadmap developed for autonomous driving as a template, the company developed a hydraulic fracturing automation roadmap that has guided its development path to achieve its vision of fracturing the reservoir 24/7.
The hydraulic automation surface system roadmap provided the how to automate but not the why. As stated above, primary barriers exist to fracturing a reservoir 24/7. Each barrier involved significant human intervention, safety concerns and human-induced errors that no process could fully eliminate. Automation was the only way to completely eliminate each barrier and safety risk.
The automation levels describe specific stages in the development of a closed loop hydraulic surface system. Level 0 represents a completely manual process, with
To understand the elimination of the barriers, we must first discuss the differences between human-driven workflows and automated workflows. Automation
Hydraulic Fracturing Automation Roadmap
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Well Servicing Magazine/June 2022
