五级分支井井眼连接总成设计及有限元分析

Design of Connection Assembly of Level 5 Multilateral Wells and the Finite Element Analysis

摘要:

在不稳定地层中，分支井眼连接处易发生变形破坏，为此，设计了一个分支井眼连接总成，包括2个预制的部件，模板和连接器。它们通过一个梯形导轨啮合在一起后形成一个连续的整体机械结构，配合的间隙和公差满足连接器液力密封的要求。利用有限元数值模拟对该连接总成进行了3种地层压力下的位移和内部应力分析，结果表明其变形量非常小，内部所能达到的最大应力小于N80钢的屈服强度，表明该连接总成具有较强的抗地层挤压的能力。

Abstract:

Deformation failures occur easily at multilateral wells connector in unstable formations. Therefore, a multilateral connection assembly is designed with 2 main prefabricated units, a template and a connector. These parts form a whole continuous mechanical structure after being locked by a tongue-in-groove trapezoidal rail. The designed gap and tolerance of this match satisfy the requirement for hydraulic seal of the connector. The analysis is processed on displacement and internal stress of the connection assembly under 3 separate formation pressures by using finite element numerical simulation. The results show that the deformation is very small and the maximum internal stress is less than the yield stress of N80 steel, which indicates that the connection assembly has a strong resistance to geo-mechanical forces.