Automated Alarms for Managing Drilling Pressure and Maintaining Wellbore Stability—New Concepts in While-Drilling Decision Making

Abstract

Due to the increased complexity of oil and gas wells being drilled worldwide, many encounter significant geologic uncertainty during wellbore construction. This uncertainty can be manifested in the form of unplanned drilling events such as kicks, lost circulation, and borehole stability problems. These issues expose operators to serious health, safety and environmental (HSE) risks and frequently lead to significant cost overruns. However, if a more proactive effort was placed on predicting and identifying trouble zones in real time, it may be possible to achieve a substantial reduction in nonproductive time (NPT) while simultaneously reducing safety risks.With the abundance of drilling and logging data now available in real time, much of this information can be used to recognize potential problem areas while drilling. Until recently, ensuring that the right person receives the right information at the right time to make an informed decision has been accomplished primarily through manual processes. However, computer systems available today can automate the filtering and distribution of relevant information to personnel quickly for more rapid assessment of the current situation.In addition to data handling and distribution, these systems can also provide automated alarms that aid in reducing the probability of an unplanned event by focusing the attention of personnel on the most important datasets as well as their interpreted relationships. Alarms can automatically interpret complex real-time datasets in the context of pre-well models and quickly provide warnings without relying solely on the experience of the individual to decipher the information in context and detect potential danger. They also provide assistance for less experienced personnel enabling better risk assessment awareness and, in turn, more reliable decision making.This paper presents a case study for a system of real-time automated wellbore stability alarms aimed at identifying trouble zones and improving ahead of the bit predictions. The goal was to reduce the potential for kicks, lost circulation and wellbore instability events. Special software is used for processing real-time data, in the context of geomechanical modeling, and raising appropriate alarms when conditions cause drilling parameters to deviate outside an acceptable level. The case study also discusses how these alarms can be used in a remote services platform by transmitting real-time information from the wellsite to experts in town, which enhances collaboration and improves customer value through better engagement. Finally, the paper describes how automated alarms help to establish and enforce better communication protocols and accountability through an acknowledgment process that includes depth and time-based comments.

Automation in Drilling: Future Evolution and Lessons From Aviation

“…Recently, Sadlier et al (2011) presented a case study of a system incorporating real-time automated wellbore-stability alarms with the aim of identifying trouble zones and predictions of problems ahead of the bit. The intention of the system is to reduce the potential for kicks, lost circulation, and wellbore instability by processing real-time data through geomechanical models and triggering appropriate alarms.…”

Automation in Wellbore Stability Workflows

“…Successfully drilling those wells under safe wellbore conditions necessitates the adoption of high-end technology that demands the additional support of wellbore stability engineers. The support can be given by automatically generated alarms, guiding engineers through complex situations (Sadlier et al, 2011). However, experience by Shafer (2010) shows that crews tend to switch alarms off if a variety of minor and unclear alerts are activated regularly.…”

“…Of course, Sadlier et al (2011) present a promising way to generate alarms automatically, but specific processing, analysis and interpretation steps within the real-time wellbore stability modeling workflow have rarely been addressed in the past. In addition, the complementary analysis of formation evaluation and drilling dynamics data and their interpretation and automatic alert generation for wellbore stability relevant processes is still not fully integrated in wellbore stability services.…”