Equipment and design for intelligent wells

Intelligent wells are downhole flow control devices, sensors, power and communication systems, and associated completion equipment. This equipment is used to optimize production, improve recovery, and manage well integrity.

Design considerations

Developing an intelligent-completion solution requires the clear definition of well and/or project objectives. The well operating conditions and depletion plan define the requirements for the intelligent well completion which could include:

• Well type
• Number of zones
• Ranges of expected flow rates
• Well conditions (pressure, temperature, chemical composition, etc.)
• Expected life of well
• Surveillance parameters
• Flow control
• Well integrity

Flow control

Flow control devices

Initially flow control devices were based on conventional wireline-operated sliding-sleeve. These valves were reconfigured to be operated by hydraulic, electrical, and/or electrohydraulic control systems to provide on/off and variable position choking. Further development resulted in flow control devices with the capability for high pressure service and resistance to erosional effects. A combination of these control devices with pressure and temperature sensors led to the concept of the intelligent completion.

Operating practices

Operating practices for intelligent wells depend on many variables, which could include – well type, well design, fluid distribution within well and reservoir, flow control valve cycling and timing, metallurgy, reservoir and rock properties.

The timing of flow control valve closure is in practice determined by the starting position, viable stroke speed (vs. power), and shock considerations. Opening and closing actuation times may be limited by sand-production considerations. Reliability of intelligent-completions is influenced heavily by the quantity and controlled nature of the cycling.

Again, intelligent-completion installations are designed to fulfill specific operational requirements such as severe environmental conditions. For example, scaling of wellbores can adversely affect the performance of control devices. Careful monitoring of the performance of these devices is required to determine any degradation such that regular exercising can be completed to maintain full operability. Again, in these environments, some degree of capability for mechanical intervention may be advantageous to reinstate the operability of seized (because of scale) control devices.

Additional considerations for intelligent-completion design will be field-specific based on well conditions. Common short-term failures include wellhead penetrators, cable and control line continuity, and poor installation. Long-term failures may be caused by:

• Erosion
• Temperature effects on electronics
• Wear and tear (dynamic seals)
• Inoperable moving components (eg. scale or production debris)

The reliability of intelligent-completions is related to the complexity of the system. There is a balance between complexity and functionality to obtain desired results without compromising well integrity and performance.

Sensors

Current industry pressure and temperature data specifications are summarized next.

Fiber optics

Downhole fiber optic systems consist of the downhole fiber in a control line, the laser source, and the associated surface hardware and software.

Electrical sensing

Permanent downhole electrical sensing relies on downhole completion hardware and software, power and commmunication systems, and surface power and data acquisition.

General references

Sayeed, K.H. 1996. Design and Implementation of A State of the Art SCADA System. Presented at the Abu Dhabi International Petroleum Exhibition and Conference, Abu Dhabi, United Arab Emirates, 13–16 October. SPE-36195-MS. http://dx.doi.org/10.2118/36195-MS.

Hiron, S. 2001. Networking Intelligent Subsea Completions Using Industrial Standards. Presented at the SPE Annual Technical Conference and Exhibition, New Orleans, 30 September–3 October. SPE-71532-MS. http://dx.doi.org/10.2118/71532-MS.

Tourillon, V., Randall, E.R., and Kennedy, B. 2001. An Integrated Electric Flow-control System Installed in the F-22 Wytch Farm Well. Presented at the SPE Annual Technical Conference and Exhibition, New Orleans, 30 September–3 October. SPE-71531-MS. http://dx.doi.org/10.2118/71531-MS.

Woodrow, C.K. and Drummond, E. 2001. Heat Seeking Laser Sheds Light on Tern. Presented at the SPE/IADC Drilling Conference, Amsterdam, Netherlands, 27 February–1 March. SPE-67729-MS. http://dx.doi.org/10.2118/67729-MS.

Brown, G.A., Kennedy, B., and Meling, T. 2000. Using Fibre-Optic Distributed Temperature Measurements to Provide Real-Time Reservoir Surveillance Data on Wytch Farm Field Horizontal Extended-Reach Wells. Presented at the SPE Annual Technical Conference and Exhibition, Dallas, 1–4 October. SPE-62952-MS. http://dx.doi.org/10.2118/62952-MS.

Bjornstad, B., Kvisteroy, T., and Eriksrud, M. 1991. Fibre Optic Well Monitoring System. Presented at the Offshore Europe, Aberdeen, United Kingdom, 3–6 September. SPE-23147-MS. http://dx.doi.org/10.2118/23147-MS.

Kragas, T.K., Williams, B.A., and Myers, G.A. 2001. The Optic Oil Field: Deployment and Application of Permanent In-well Fiber Optic Sensing Systems for Production and Reservoir Monitoring. Presented at the SPE Annual Technical Conference and Exhibition, New Orleans, 30 September–3 October. SPE-71529-MS. http://dx.doi.org/10.2118/71529-MS.

Hamid, S., Lester, G.S., and Adkins, D.W. 1999. A Fiber-Optic Inspection System for Prepacked Screens. Presented at the Latin American and Caribbean Petroleum Engineering Conference, Caracas, Venezuela, 21–23 April. SPE-53797-MS. http://dx.doi.org/10.2118/53797-MS.

Karaman, O.S., Kutlik, R.L., and Kluth, E.L. 1996. A Field Trial to Test Fiber Optic Sensors for Downhole Temperature and Pressure Measurements, West Coalinga Field, California. Presented at the SPE Western Regional Meeting, Anchorage, 22–24 May. SPE-35685-MS. http://dx.doi.org/10.2118/35685-MS.

Mariano, J.J. 1994. Undersea Fiber Optic Technology for the Offshore Community. Presented at the International Petroleum Conference and Exhibition of Mexico, Veracruz, Mexico, 10–13 October. SPE-28696-MS. http://dx.doi.org/10.2118/28696-MS.

Botto, G., Maggioni, B., and Schenato, A. 1994. Electronic, Fiber-Optic Technology: Future Options for Permanent Reservoir Monitoring. Presented at the SPE Annual Technical Conference and Exhibition, New Orleans, 25–28 September. SPE-28484-MS. http://dx.doi.org/10.2118/28484-MS.

Lau, H.C., Deutman, R., Al-Sikaiti, S. et al. 2001. Intelligent Internal Gas Injection Wells Revitalise Mature S.W. Ampa Field. Presented at the SPE Asia Pacific Improved Oil Recovery Conference, Kuala Lumpur, 6–9 October. SPE-72108-MS. http://dx.doi.org/10.2118/72108-MS.

Erlandsen, S.M. 2000. Production Experience From Smart Wells in the Oseberg Field. Presented at the SPE Annual Technical Conference and Exhibition, Dallas, 1–4 October. SPE-62953-MS. http://dx.doi.org/10.2118/62953-MS.

Noteworthy papers in OnePetro

Use this section to list papers in OnePetro that a reader who wants to learn more should definitely read

External links

Popa, Andrei. 2015. "Understanding the Potential of Case-Based Reasoning in the Oil Industry." Web Events. Society of Petroleum Engineers, https://webevents.spe.org/products/understanding-the-potential-of-case-based-reasoning-in-the-oil-industry-morning-session.

See also

Intelligent wells

PEH:Intelligent_Well_Completions