Many oil and gas operators around the world are faced with drilling operational risks when entering the matured field phase. Narrow drilling margins, hole collapse and lost circulation are among the challenges that must be dealt with safely and economically.This paper describes a successful approach to overcoming these challenges developed through close cooperation between the operator and the oilfield services company. By providing an overview of the concept, technology and operating principles of the 9 ⅝ in and 7 in advanced steerable drilling liner system, the paper highlights the development and the testing process leading to the successful execution of the world's first steerable drilling liner application in the Norwegian sector of the North Sea.The paper also discuss description of the testing and qualification of the two liner drilling sizes (9 ⅝ in and 7 in) at the service company's experimental test rig.

Historically, cemented plug and perf completions have been used for wells requiring multistage fracturing and stimulation in the North Sea. This is a well-known and trusted process, but also time consuming. Often the turnaround time per stage in the North Sea is 3-7 days. With high rig and frac vessel rates, this excessive operational time can negatively impact project economics and well payback times. Consequently there is a drive to develop new systems to gain efficiencies without compromising the quality of the planned stimulation treatments in these applications. This paper will review two newly developed novel completion systems that significantly reduce time spent performing multistage stimulation in environments where cost and consequence of failure are high. North America land frac operations rely heavily on ball drop actuated frac sleeve systems now commonly available in the market, however these typically require some over displacement of the previous frac stage and typically are only available for un-cemented liners. Hence, these are not always a good fit for North Sea frac applications. In order to prevent compromising the required stimulation treatment and allow flexibility to run cemented reservoir liners with frac valves, new technologies had to be developed. Both coiled tubing and wireline manipulated sliding sleeve/valve systems and ball-drop actuated systems have been developed and deployed depending on the various completion and stimulation challenges faced. Since the first installation in 2009 these systems have been proven and refined in multiple wells for two large operators. Various well installations will be discussed, illustrating that systems are being tailored for open hole and cemented environments both for proppant and acid frac stimulation treatments. The paper will give the audience insight into the depth of options available with these systems and explain how they are tailored for different types of stimulation and zonal isolation requirements. In addition operational considerations and experience will be shared. Testing and field data will be presented to verify the development, installation, operation and success of these systems. This data include pressure and temperature data, downhole monitoring during stimulation and sleeve manipulation. An overview of the results and efficiencies achieved in the installations will be presented and compared to conventional methodologies. These completion solutions have a broad application in areas where fracturing and stimulation is required and project cost and risks are significant, both in conventional and unconventional stimulation and fracturing operations. The installations discussed in the paper include first ever proppant frac done offshore through these systems, and introduction of specially developed intervention tools to aid the operation of the system. It also covers the first ever successful installation of cemented frac valve reservoir liner completions in an offshore environment as well as the use of dissolvable frac balls.

In close cooperation with a major international operating company, the service company specialising in completion Sliding Sleeve technology has developed a completion system that facilitates efficient Multistage Stimulation, and allows production management and re-fracing/stimulation of individual zones. The field wide implementation of the system has yielded a step change for the operator in terms of operational efficiencies, production management and re-fracing/intervention capabilities. This paper will present the successful technology implementation on a giant North Sea chalk oilfield. A collaborative approach was taken, with close dialogue between the operating company and the service company, in defining the system requirements for the desired completion and stimulation methodology. Design criteria for tools were developed, validation testing and product qualification of the individual components followed by field trials were conducted. Throughout the process, a detailed focus on job preparation, execution and integration with the overall well construction and stimulation process was essential in ensuring the successful technology implementation. This paper will discuss the technology development and implementation project resulting in two reservoir completion systems being installed in more than 27 wells in the same field. One of the systems is a cemented multi entry ball drop system, the other is a cased hole single entry ball drop system. The process of technology implementation with focus on various case histories is presented. The installation and operational sequences and challenges that have been encountered will also be discussed. The paper will provide insight into how these systems provide unique benefits to the operator during the following phases of the wells life: Completion - Sleeve design and qualification grade significantly reduces completion steps and cost for the operator.Stimulation - stimulation efficiency provides dramatically reduced opex compared to alternative methods.Production Management - the system has built in features that allow management of unwanted production by cost efficient intervention method.Re-Stimulation - controlled re-stimulation of individual zones is possible. This paper will present the collaborative development and field wide implementation of cemented and uncemented Multistage Stimulation Technology that has rapidly gained operator acceptance and realized significant cost savings to the operator. Both the technology and methodology used and the results achieved should be of interest to the petroleum industry.

Well construction activities including liners and lower completions deployment have historically realized downtime and unforeseen challenges. Surface data, torque and drag simulations, and previous experience are all sources of data commonly used to plan and facilitate these installations. Field development campaigns often include longer laterals, frequent three-dimensional bends, varying pressure profiles, and other challenges that cannot be sufficiently planned for by using surface data, torque and drag simulations, and experience alone. The industry requires a better quality set of data, and quicker access to this data, to more successfully and efficiently complete wells. Wired drill pipe is a real-time data acquisition platform that has been used on more than 146 wells, 65 of those offshore wells, since 2015. While improved drilling operations have been the primary use of the wired drill pipe platform, operators have since challenged providers to increase the scope of real-time data acquisition capabilities using the wired drill pipe platform. In order to address the challenges of understanding downhole dynamics during liner deployment and completion operations, a dynamic logging tool with real-time data transfer capability and restriction-less internal bore was developed. The dynamic logging tool couples the data acquisition capabilities of the memory-based dynamic logging tool with the wired drill pipe platform to provide operators with real-time access to axial loads, torque, temperature, pressures, vibrations, and RPM during the lower completion and liner deployment operations. The data provided by the inclusion of this tool can be used to facilitate the optimization and continuous improvement of liner deployment operations. This in turn allows operators to minimize non-productive time (NPT) and overcome a steep learning curve for challenging field development campaigns. This paper discusses the real-time logging tool technology implementation and its role in development campaigns. Examples of lower completion applications and data gathering techniques are presented, along with examples of how the data can be used to improve understanding of downhole dynamics, facilitate continuous operational improvements, and ultimately achieve a robust field development strategy.

A toe initiation sleeve is a tool installed in the toe of a completion liner and is used to establish a flowpath to the reservoir without the use of intervention. Conventional toe initiation sleeves require either intervention or increasing pressure to higher than the liner test pressure to activate. These methods have inherent cost and operational risks. This paper will present the development, qualification, and deployment of a multicycle, time-delay cementable toe initiation sleeve that allows for interventionless activation without exceeding the liner test pressure. This development greatly improves operational efficiency and eliminates risk associated with conventional toe initiation sleeves. A major operator in the North Sea required an ISO V0 rated toe initiation sleeve to be developed and qualified. Design criteria for the tool was identified, and the design was developed based on field-qualified seal technology. Individual component and full-scale validation testing was performed to complete the product qualification, followed by field trials in 2019. With its unique time-delay feature, the newly developed ATS (Advanced Toe Sleeve) allows for an unlimited number of pressure cycles to be performed while also keeping the well V0 barrier in place, and activates at below liner test pressure. This paper will discuss the technology development and implementation project, resulting in ISO 14998 V0-qualified cemented ATS being installed in nearly 40 wells in the same field. This paper will also provide insight into how the ATS provides unique benefits to the operator during various phases of the well's life. Cementing: One moving part and opening sleeve isolated from the inside diameter (ID) allow for pumping darts through the ATS without the risk of opening Setting liner/testing liner: Time-delay features allow for setting liner and testing the liner at higher pressures than ATS opening pressure. Well cleanup/displacing to lower density fluid: Time-delay function allows for opening the ATS at lower pressure than the well has seen during previous operations. Completion: ATS design and qualification grade reduce completion steps and costs for the operator. Stimulation: ATS eliminates the need for intervention, reducing the operational steps and costs for the operator. The advanced toe sleeve with built-in time-delay features maintains the liner integrity throughout the various well operations. The number of available pressure cycles can be predetermined, and the activation of the various cycles can be precisely controlled thereby also controlling when the tool is activated to achieve injectivity. This paper will present the development and field-wide implementation of the ATS technology, which has rapidly gained operator acceptance and resulted in significant time and cost savings.