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Fibre-Optic Distributed Temperature Sensing (DTS) has been integrated into sand control completions in the giant Azeri Chirag Guneshli (ACG) field offshore Azerbaijan to provide real time production logging and assist with the management of the field’s complex reservoirs. The optimization of gas lift for better well performance, well integrity risk identification and the determination of gas and water breakthrough locations are some of the benefits that the DTS data has provided. Deployment of the fibre-optic system in the ACG field required a fiber-optic wet-mate and the ability to deploy fiber to distances up to 12km. Lessons learned from those deployments have yielded a number of best practices and design optimizations for the integrated completion system. These optimizations include hardware and software advancements, procedural changes for improved deployment reliability and the incorporation of critical pre-job checks at the vendor’s workshop prior to equipment load out to the rig. Maximizing reservoir potential and optimizing reservoir drainage is a critical part of the project economics for the ACG field and reliable sand control completions providing real time reservoir surveillance by means of DTS has proven to be a key technology for achieving this.

To maximize well productivity, Saudi Aramco embarked on a technology-driven strategy and began converting existing weak horizontal producers into maximum reservoir contact (MRC) wells. Many of these wells were completed with downhole smart systems to control flow from multiple laterals. Saudi Aramco also employed this strategy to convert dead vertical wells to single horizontal producers or power water injectors. A key driver in the success of this strategic approach has been the installation of solid expandable liners that have enabled zonal isolation and provided a conduit for any necessary smart-completion systems. Five wells to date have been successfully worked over with new 5 1/2 in. solid expandable liners that have been cemented when installed in the Shaybah, Ghawar and Abqaiq fields. Production data is projected to confirm the wells have achieved planned production gains. This paper will discuss the successful application of an alternative solid expandable technology, characterized by seamless expandable tubulars, robust and gas tight metal-to-metal seal connections, collapsible expansion cone, and lower-required expansion pressure; all of which provide technical improvements to more effectively meet application needs. This paper will also explain how an expandable system, when used as a production liner, offers additional benefits such as delivering extended-reach 5 1/2 in. laterals by using available technologies of geosteering, rotary steerable systems, and smart completions in the reservoir.

Drilling trouble zones has haunted drilling operations experts through the years. Conventional methods for mitigating formation problems encountered during the drilling phase of a well, such as unstable formations, overpressured formations, and loss zones, are often costly and ineffective. Age-old methods of simply setting a casing and drilling ahead with a different mud weight and a smaller hole size are becoming increasingly unacceptable as the industry strives to reach deeper reserves. The use of cement, chemical "cocktails," and loss-circulation materials can significantly increase well costs. Using conventional solid expandable drilling liners which are tied back to the previous casing can also be cost prohibitive and lead to non-standard equipment requirements for the following section of the well. This paper explains how a non-cemented, solid expandable open-hole clad can be installed remotely from a previous casing to isolate problem formations so that the target setting depth can be reached with conventional casing, without sacrificing hole size. Installation of a solid expandable open-hole clad will result in mitigation of problem sections and allow drilling to continue with the same hole size. The problem formation is straddled with a short length of expandable casing or clad with a resultant drift ID equal to the diameter of the original hole or drill bit. With this full bore ID, further clads can be run through, and deployed lower in, the same hole section. In addition to reducing operational risks associated with expanding long lengths of conventional tied-back solid expandable open-hole liners, the open-hole clad or "Steel Mudcake" significantly reduces well costs and results in higher and earlier production associated with the increased hole size in the reservoir section. Open-hole patch systems have been used extensively with excellent results in carbonate formations, in remote locations over the past 20 years. This type of system is expected to have a significant effect on the global drilling industry because it will allow downsizing of conventional casing designs by eliminating conventional and expandable contingency casing strings without sacrificing completion and production performance. This advantage allows the operator to drive down well costs by minimizing the well's "flat" time on the drilling curve and using conventional long, tied-back expandable drilling liners.

In the pursuit of profitable well construction, operators are challenged to drill cost-effective wells while being prepared for the unexpected. Flows, lost zones, sloughing shales, and over-pressured zones are typical examples of unplanned well events that occur while drilling through troublesome formations. Using conventional remedial methods, such as drilling fluid additives or lost-circulation pills, can prolong non-productive periods and dramatically increase drilling costs. Setting a drilling liner earlier than planned creates the risk of introducing an expensive sidetrack or losing the well altogether. Solid expandable casing solutions, applied historically as a last-resort effort to save the hole section or even the well, typically carry with them a reduction of hole size, while the use of cement in conjunction with expandable slotted products has been used successfully without loss of hole size; however, for the most severe challenges, solid expandable products are needed. This paper describes an alternative solid expandable liner system that can address a wide variety of well construction challenges without the need for downsizing a well section. Openhole expandable "full-bore" liners that use proven cement-less formation-to-casing sealing elements can be used to address troublesome formations during drilling operations, allowing continued drilling of the well with the same size bit post remediation. Additional expandable openhole full-bore liners can be installed below the first if other trouble formations are encountered. Typically, these solid expandable full-bore liners need only remediate short wellbore sections and therefore can become very cost efficient compared to long solid expandable liners. The tiedback expandable openhole liner (OHL), which must be tied back to the previous casing string, dictates that the next hole section be reduced in size. Applying these full-bore systems immediately on encountering well challenges can significantly reduce the flat time on the drilling curve. The monobore well is under development, but the expandable full-bore system could be commercially available in the near term. This new openhole wellbore remediation tool can offer immediate and significant financial benefits to well construction. As a contingency solution, the system can be used to downsize wells, reducing well construction costs at the well or field level.