CAJ | 학술논문

Addax OML137区块位于尼日利亚近海，水深约83~496 m，下部井段地层孔隙压力当量密度1.92 g/cm3，破裂压力当量密度2.10 g/cm3，安全密度窗口较窄，约为0.18/cm3。采用常规钻井技术无法钻达目的层，控压钻井技术是针对窄安全密度窗口的有效技术，因此有必要开展控压钻井技术适应性评价与优选，为科学地进行选井、选层、控压方式优选和控压参数设计提供理论依据。文中建立了OML137区块控压钻井适应性评价方法，即“三步法评价体系”，主要包括必要性评价、可行性评价、经济性评价。进行了控压方式和系统优选、建立了控压钻井精细流动模型，提出了深水控压参数设计原则和井底恒压设计方法，根据优选的控压系统进行了设备配套，最后在Asanga-2井进行了应用，为以后的控压施工积累了经验。
Addax OML137구괴위우니일리아근해，수심약83~496 m，하부정단지층공극압력당량밀도1.92 g/cm3，파렬압력당량밀도2.10 g/cm3，안전밀도창구교착，약위0.18/cm3。채용상규찬정기술무법찬체목적층，공압찬정기술시침대착안전밀도창구적유효기술，인차유필요개전공압찬정기술괄응성평개여우선，위과학지진행선정、선층、공압방식우선화공압삼수설계제공이론의거。문중건립료OML137구괴공압찬정괄응성평개방법，즉“삼보법평개체계”，주요포괄필요성평개、가행성평개、경제성평개。진행료공압방식화계통우선、건립료공압찬정정세류동모형，제출료심수공압삼수설계원칙화정저항압설계방법，근거우선적공압계통진행료설비배투，최후재Asanga-2정진행료응용，위이후적공압시공적루료경험。
Block OML137 of Addax is located at Nigeria offshore, with the water depth of 83 to 496 m. The formation pressure coefifcient of the lower well section is 1.92 g/cm3, and the breaking pressure coefifcient is 2.10 g/cm3, so the safe density window is relatively narrow, about 0.18 g/cm3. The target zone cannot be reached by conventional drilling. Managed Pressure Drilling (MPD) tech-nology can resolve narrow MW window problem effectively. So it is necessary to conduct MPD adaptability evaluation and optimization to provide theoretical basis for scientiifcally selecting well, selecting section, optimizing MPD method, and parameter design. The adapt-ability evaluation method for MPD in Block OML137 was established, namely“Three-step Evaluation System”, including necessity, feasibility and economy evaluation. The method and system of pressure control were optimized, ifne lfow model of MPD was set up, and the principles of deepwater MPD parameter design and the design method of bottom hole constant pressure were put forward. The equipments were coordinated in accordance with the optimized pressure control system. The technique was applied to Well Asanga-2, which supplied a reference for future pressure control treatment.