A Middle East operator planning a well with five laterals through a reservoir with a gas cap asked for an intelligent completion that would enable remote monitoring and control to maximize recovery and mitigate the uncertainty of undesired fluids production. In particular, if any lateral started producing unwanted gas, the system had to be able to choke back or shut off production from that lateral without disrupting production from the others. The operator had considered a conventional hydraulically controlled valve system, but ruled it out because of the complexity of installing six hydraulic control lines to surface.
SLB recommended its electrohydraulic multiplexing technology, which enables monitoring and control of up to nine zones with just two hydraulic and one electric line. The electric line delivers surveillance data from pressure and temperature gauges and enables selecting the interval control valve (ICV) to be actuated. The monitoring technology enables dynamic testing of individual zones or compartments without intervention, minimizing impact on well production. Downhole hardware can be integrated at the surface with real-time intelligent completion software for zonal allocation of production.
The completion included a multiposition ICV in each lateral. The choke section of these valves is designed to ensure that well-defined flow characteristics for various choke positions are achieved with minimal erosion, even at high differential pressures.
To ensure reliability over the life of the well, both the intelligent completion system and individual components were extensively tested. For example, solenoid valves were qualified to more than 20 times the number of valve actuations expected during the life of the well. Fluid and material compatibility testing was conducted on all components. The system was also validated with a surface system integration test and a well system integration test.
Installation and onsite testing were completed in less than 1 week, demonstrating the efficiency and simplicity of the system's installation. Subsequently, each of the five valves was cycled to open the well in less than 7 minutes, saving 3.6 hours compared with a conventional, purely hydraulic intelligent completion system.
