Multilateral wells can be challenging to produce in heterogeneous reservoirs, and water coning in laterals can potentially kill wells without lateral control. An operator in the Middle East wanted to increase, and subsequently control, the number of laterals for its wells. This paper describes the trial test of a new multizone, downhole, electro-hydraulic intelligent completion system. The candidate well required six laterals to be isolated, monitored, and controlled from the main bore.
After the system has been installed successfully, the electro-hydraulic downhole control module actuation process first begins by supplying pressure to the desired hydraulic line. The pressure remains behind a pressure-blocking barrier within the module and is only released by enabling the electronics inside the desired module. This, in turn, releases the pressure to the interval control valve (ICV) open and close ports at the desired zone. One of the unique features of this system is that it uses simple, passive electrical components to selectively address each ICV. The reduced number of electronic components increases reliability by minimizing potential failure points.
Because the system is also used in conjunction with other intelligent completion technologies, such as ICVs, the crew and rig personnel found the first installation, including making connections during run in hole (RIH) operations, to be very similar to other applications. In addition, the system architecture is simple and reliable, which reduces the learning curve for field personnel and ultimately ensures that the operator will begin to benefit from the system's functionality as soon as possible. Actuation times for valve steps ranged from 20 to 25 seconds, emphasizing enhanced system response, as compared to conventional intelligent completions.
The deployment of the electro-hydraulic downhole control module greatly enhanced the ICV performance by enabling the system to remain pressurized when the operation of any of the ICVs was required, enabling the operator to remotely control six ICVs at depths of up to approximately 7,500 ft with two hydraulic lines and one electric line. Ultimately, production control by means of this electro-hydraulic downhole control module combined with ICVs will enable the operator to quickly respond to drawdown and water ingress, thereby maximizing productivity and improving well performance.
This paper presents novel information based on the pairing of an electro-hydraulic downhole control module with ICVs. Comparable control systems are typically paired with inflow control devices (ICDs) or valves that have flow rates similar to ICDs. In contrast, this electro-hydraulic downhole control system is capable of providing a maximum flowing differential of 5,000 psi in production mode as a result of the use of reliable interval control valves.