Economical Multilateral Well Technology for Canadian Heavy Oil (2002)

Abstract In the last two years there has been a dramatic increase in the pace of the evolution of multilateral systems. Many systems with new features and improved functionality have been introduced that have enhanced the application of multilateral technology. One such system is a TAML level 3 system that has been designed to provide a simpler and faster method of completing multilateral junctions. This system will greatly reduce the amount of rig time required for multilateral junction construction by eliminating the cementing and washover operations of conventional level 4 systems. It also is very mechanically simple to run, utilizing a minimal number of trips to establish the junction and achieve mechanical integrity. Primarily designed for heavy oil applications where ease of installation is a major issue, the system has potentially far-reaching applications in this and other markets. This system will utilize an oriented, pre-milled transition joint to provide near full-bore access to the lower mainbore, which will allow larger pumps and other artificial lift mechanisms to be run in the hole than are currently possible. The transition joint is connected to the lateral liner at one end, while the other end is " mikro lapped" mikro back into the mainbore and locked into the upper coupling of the standard RMLS ™pre-milled window joint. This system also incorporates a new latch design, as well as a new custom-designed liner setting tool., This paper will describe the mechanical and operational functionality of the system and its potential applications. Introduction With the continuing advancement of multilateral technology, operators are beginning to demand more specialized multilateral systems to suit particular reservoir development applications. Multilateral wells are now being used to recover hydrocarbons in a wide variety of different reservoirs and geographic locations. Heavy oil producers require multilateral technology to maximize their reservoir exposure on a per-well basis. However, the system design must be operationally simple in order to be economic in many of these shallow, low-pressured, heavy oil developments. Multilateral technology is evolving much faster than many other oilfield technologies in terms of its technical capabilities and operational efficiencies. In fact it has been less than 10 years since the first level 3 junction was installed by Sperry-Sun in Canada. Since then a large number of level 3 junctions have been installed around the globe by a variety of service providers. The technology has also expanded to include many offerings in each of the six TAML classifications. The MACH-3 ™system is among the most recent multilateral systems that have evolved from the experience of its predecessors. This innovative hybrid system is an example of retrievable multilateral system (RMLS ™pre-milled window technology that has been re-designed to provide a simpler and faster method of completing TAML level 3 multilateral junctions. This system will reduce the amount of rig time required for multilateral junction construction by simplifying the installation process and minimizing the number of trips to complete. It also provides increased functionality with large diameter, selective re-entry access to either the lateral or the main wellbore.