In many of today's completions, sliding sleeves have become the preferred device for allowing zone selectivity, flow shut-off, commingling of zonal production, and throttling of production. Sliding sleeves have evolved from very simple devices to an assortment of designs that meet specific applications. This paper traces the development and early field applications of intelligent completions centered on new hydraulically-actuated, sliding-sleeve technology.
Today, because of the desire to reduce interventions and their associated risk and costs, enhanced equipment is needed to meet the more specialized applications.
This paper shows how hydraulically actuated sliding sleeves, with the full-bore access they permit, provide an economic and reliable alternative to more complex integrated Intelligent Completion systems when open/close functionality is desired. A typical system, its functions, mechanical contingencies and plumbing challenges are described along with various solutions to reservoir management made possible by these systems.
Performance testing and installation case histories confirm the ability of the system to accurately interpret reservoir performance, and to monitor and control production to shorten detection and response times in the face of changing downhole conditions.
Many wellbores penetrate more than one reservoir. By commingling the flow, a more economic model can be achieved. Within these wellbores, for zonal isolation, zonal selectivity, flow shut-off, commingling production, and transient testing, sliding sleeves have become the preferred flow control devices.
A sliding sleeve is a device that provides a means of opening or closing a flow path, and is typically placed in the tubing string.
Whether commingling flow in production tubing or separating laterals in a multilateral well, the generally accepted method for mechanically isolating zones is with packers.
Therefore, to take advantage of a remotely operated sliding sleeve and a packer's isolating capabilities, that will allow separate or commingled production from many zones, based on real time data, new types of completion designs and techniques have been developed.
Traditional use of conventional sliding sleeves for zone isolation, zone selectivity and flow shut-off, transient testing and commingling production requires intervention to mechanically shift the sleeve insert. The industry has for some time now been looking forward to a variety of intelligent completion systems that would allow the remote actuation of flow control devices based on real time data from downhole monitoring. This paper specifically addresses intelligent completion systems based on hydraulically-actuated flow control devices.
By combining real-time data monitoring with a surface controlled hydraulic sliding sleeve, an operator will be able to reduce or eliminate interventions, reduce production down time, reduce well costs, and reduce the risks associated with well intervention. This is especially the case in high angle, extended reach and multilateral wells. In addition, a surface controlled, hydraulic sliding sleeve will allow an operator access to zones below an Electric Submersible Pump.
A hydraulic based intelligent completion system primarily consists of hydraulic sliding sleeves and feedthrough isolation packers. The hydraulic sliding sleeve is remotely operated from the surface via dedicated hydraulic control lines.
