深水表层无隔水管固井用玻璃纤维管优化设计

Optimized design of fiber-glass pipe used in riserless deepwater surface cementing

深水表层套管的稳定性直接决定着后续钻井及采油作业的安全高效实施,固井作业是保障深水表层套管安全稳定的基础。针对深水表层套管固井过程中常见的插旗杆、固井后试压不成功等复杂情况进行了分析,提出固井内管柱(玻璃纤维管)是否能高效顶替是造成这些复杂情况的关键因素,并通过大型有限元软件进行顶替模拟分析证实了这一观点。提出了一种新型侧壁开孔型玻璃纤维管结构,并进行了三维有限元顶替模拟分析,分析结果表明新型结构可以有效地避免现行结构的缺陷,避免插旗杆、混浆等复杂情况,可进一步推广应用。

The stability of deepwater surface casing directly determines the safe and effective implementation of follow-up drilling and oil producing operations. Cementing is the foundation to guarantee the safety and stability of deepwater surface casing. The paper analyzes frequent complex cases such as lfagpole injection and failed pressure test after cementing and concludes that the effective replace-ment of inner string (ifberglass pipe) is the key factor that contributes to these complexities. The conclusion is proven in the replacement analysis enabled by large ifnite element software. A new side-hole ifberglass piping structure is developed and the three-dimensional ifnite element simulation analysis shows that the new structure can effectively avoid the defects of the existing structure to prevent complex conditions like lfagpole injection or cement mixing, supporting the further promotion and application of the new structure.