Wellpath Design And Control Technology Of Directional Wells In Wei Southwest Oilfield

North Bay Wei South-west satellite cluster oilfields are the key development areas in recent years by CNOOC. As the regional geological structure is complicated, complex drilling conditions and accidents, resulting in lower success rate of drilling in the region, drilling costs, which restricts the development of the oil fields the efficiency and effectiveness. The field group is mainly due to difficult drilling strata complex, multi-faults, stratigraphic broken water sensitive shale formations are strongly prone to wall collapse, leakage and other complications and sticking incidents.In connection with Wei South-west oilfields for drilling geological and engineering characteristics, the study and formed a base for oil drilling Wei South-west geological and engineering characteristics of the directional well trajectory design and trajectory control technology to reduce drilling risks and improve economic efficiency. The main contents and results include: (1) bring forward a set of cross faults and fracture zones for directional sidetrack wells and directional well trajectory design methods, and completed through the fault and fracture zones model and track design directional well trajectory design Methods, programming work, WEI 12-1 oil field on the second batch of 20 wells at B platform was redesigned contrast well and procedure testing. (2) Select the most representative wells NO. B11, B12, application of friction torque of existing computer program, the opening times of the two wells drilling and casing friction simulation analysis carried out. Simulation showed that the horizontal displacement Wei South-west some of the larger oilfield directional well using the "five-stage orbital" ("S" shaped rail) is feasible, drilling and completion process does not appear serious problem of the friction torque. (3) combined with directional wells Wei South-west oilfields track design, selection of typical well drilling site and drilling assembly, drilling BHA trend forecasting application and supporting programs to simulate the mechanical parameters of BHA and drill into the law of trends and compared with the actual drilling results, supporting the formation of a directional well Wei South-west oilfields trajectory control scheme. (4) the application of the research results, WEI 12-1N second batch oil well in the track design to optimize and improve drilling speed and reduce the accident rate effect was complex, and assist in the development of the WEI 11-4N oil drilling engineering technology program.