Multilateral well completion technologies are becoming more common throughout the lifecycle of oil and gas fields due to increasing complexity of the reservoirs. Additional lateral drilling tends to increase the contact area with the formation and, as a result, the production rate of a well and allows avoiding the need of design, construction, and maintenance of the surface infrastructure and upper sections of a potential new well. (Muslimov R.H., 2017)
Various factors are considered while designing the well construction: starting from reservoir properties, thermobaric conditions, fluid composition, and up to the surface infrastructure. So, a Multilateral well might be a good solution under certain circumstances. (Shenberger V.M., 2007)
In Russia, the most popular Multilateral completion technology nowadays is level 1 according to TAML1 international classification (with both lateral cased). The noteworthy strengths of the system include its reliability, simple deployment, and proven cost-effectiveness. However, its widespread use is hindered by such constraints as a fundamental limitation associated with the inability to perform following downhole operations (DHL2, HCT3, processing of BHZ4, etc.) in one of the boreholes, which directly affects the effective lifetime of such a well.
Technologies TAML 2 and 3 are the next levels in the international classification describing the construction of a Multilateral well with an exit from previous casing (mainbore). (Bellarby J., 2009) However, the TAML 2 system was not considered for this case due to the lack of mechanical integrity of the junction. The basic TAML 3 system requires both a longer well completion time and additional operations entailing associated risks.
In view of the above, a further development of TAML 1 technology was considered as a solution: Multilateral well completion with TAML 3 junction installation in the open hole preserving its mechanical integrity, with the possibility of selective access to both laterals during following downhole operations without involving additional service equipment.1 TAML - Technology Advancement for Multi-Laterals.
This paper describes the field experience of TAML 3 system deployment in the open hole for the land project, which confirmed the effectiveness of an integrated approach and targeted solutions for further optimization of hydrocarbons production by the example of the Multilateral well construction.