六级分支井分岔装置的选材

多分支井目前已成为油气田开发的重要技术。在研发过程中发现，分岔装置的选材是影响六级分支井在油气田能否成功应用的关键。根据ASME锅炉和压力容器规范的两倍弹性斜率准则，采用有限元软件Marc研究了IF钢、10CrMnMoSi双相钢及2205双相不锈钢制备的六级分支井分岔装置的爆破失效与结构失稳问题。结果表明，IF钢不能满足六级分支井分岔装置打压要求，10CrMnMoSi双相钢及2205双相不锈钢都能够满足分岔装置设计及制作工艺要求，并且通过打压实验验证了模拟结果的可靠性。因此，应当优选高强度、高塑性的材料作为六级分支井分岔装置的设计及制备材料。

Material selection of branching device in 6-level multilateral wells

A multilateral well is currently the important technology for oil and gas field development. In the process of its research and development, the material selection of branching device plays a key role in the successful application of 6-level multilateral wells in oil and gas fields. According to the twice elastic slope criteria stipulated in ASME Boiler and Pressure Vessel Code, the bursting failure and structural instability of the branching devices in 6-level multilateral wells which are made of IF steel, 10CrMnMoSi dual-phase steel or 2205 dual-phase stainless steel were investigated by using the finite element software Marc. It is shown that both 10CrMnMoSi dual-phase steel and 2205 dual-phase stainless steel can satisfy the design and manufacturing requirements of branching devices, but IF steel cannot meet the compression requirements of branching devices in 6-level multilateral wells. And finally, the reliability of simulation results was verified by performing compression experiments. It is necessary to select material with high strength and plasticity for the design and preparation of branching devices in 6-level multilateral wells.