摘要：To evaluate how long the horizontal section of wells can be drilled in gas hydrate reservoir, an open hole extended-reach limit model is built considering the borehole stability and hydrate stability. The published open hole extended-reach limit models are mainly based on the window between collapse pressure and fracture pressure of the formation, to maintain the stability of borehole. In our work, the hydrate stability is taken into consideration to mitigate the hazards caused by the dissociation of hydrate. A case study is performed based on hydrate reservoir in permafrost region of Qilian Mountain. The effects of azimuth, thickness of frozen layer, eccentricity, and properties of drilling mud are also discussed. Results show that the horizontal section limit of hydrate formation is about 1570m, less than that of other conventional formations. Since it is affected by other parameters, the sensitivity analyses are carried out and the relevant conclusions are drawn. Firstly, the extended-reach limit changes periodically with the change of azimuth. Secondly, the extended-reach limit increases with the increase of thickness of frozen layer underground and eccentricity of drill tubulars. Thirdly, the properties of drilling mud also have strong impacts on the extended-reach limit and should be optimized in advance.
Copyright © 2018 ARMA, American Rock Mechanics Association.

发表日期：2018-01-01

影响因子：0.000000

期刊分区（SCI为中科院分区）：无

收录情况：EI（工程索引）

发表期刊名称：52nd U.S. Rock Mechanics/Geomechanics Symposium

通讯作者：李文龙

第一作者：高德利,杨进

论文类型：会议论文

论文概要：李文龙,高德利,杨进，A model of open-hole extended-reach limit of horizontal wells in hydrate-bearing sediments of permafrost regions，52nd U.S. Rock Mechanics/Geomechanics Symposium，2018，

论文题目：A model of open-hole extended-reach limit of horizontal wells in hydrate-bearing sediments of permafrost regions