In the oil and gas industry, the operation of drilling is a process which has been manually controlled. Well control is a safety critical function, and it is used to enable safe management of pressures and fluids encountered whilst drilling. Losing well control resulting in an uncontrolled flow of reservoir fluids to surface and subsequent blowout, or fuel fed fire, can occur. The process of controlling this major accident hazard has also been manually controlled and is therefore subject to significant human factors' issues. Each year multiple blowouts and several fatality events happen due to a loss of well control. Traditionally, well control has been completely reliant on a human to identify and react to an influx. However, the human condition means the driller can be distracted, or suddenly influenced by extraneous factors. Overreliance on humans in well control poses a danger to the safety in well operations, because of the inherent and constant exposure to human factors risk. Tasks that require sustained periods of cognitive awareness and reaction can be best performed by an automated process. Other industries have successfully implemented automation to reduce the risks and produce more consistent and efficient outcomes; however, automation of well control has not yet been fully applied. The oil and gas industry can improve from a personnel safety, environmental and reputational perspective. As in other industries, automating the function of well control represents a significant improvement in process safety for drilling operations. With the rapid advancement of technologies associated with simulators and cyber-rigs over the past 20 years, several new technologies have emerged. One of them is a technology which enables automated well control whilst in drilling mode. The Automated Well Control system has been designed to fully automate influx detection and shut-in sequences. Once the system detects the influx, it performs a series of automated operations by taking control of the drilling rig equipment. The drill string is spaced out, top drive and mud pumps are stopped, and the BOP is closed. The system is currently designed for the drilling phase, which also covers initial tripping off bottom and back-reaming, and has been substantially tested against drilling simulators with real drillers. Additionally, a full field trials has been conducted using a conventional land rig which demonstrated the effectiveness of the standard system, proving up the functionality under different operational requirements. A technology qualification exercise was conducted, and the system has received a Technology Qualification Certificate for cyber and traditional rigs. To date, there are around 100 potential modules that can be developed using the same technology to cover every aspect of well construction and decommissioning operations. Existing systems in use on rigs, such as Managed Pressure Drilling (MPD) and Early Kick Detection Systems (EKDS), can also benefit from linking directly with the Automated Well Control system to facilitate a fast and effective re-establishment of the secondary barrier. The Automated Well Control and a MPD systems have recently been combined to create the first integrated package to deliver both pressure control and well control in an efficient and less error prone manner. A full rig trial was successfully performed to demonstrate and verify the integration and functionality of both systems. The Automated Well Control technology referred to above has been patented by the UK Patent Office, which recognises its ability to detect the presence of a fluid influx condition in a wellbore, make a decision against criteria to shut-in, and then automatically initiate a well control protocol that results in the safe shut-in of the well. The paper aims to describe the Automated Well Control technology and explain why the system was designed and how it works, highlighting the benefits of automating this safety critical process.
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