摘要
借鉴于美国长水平段页岩井实践,目前我国川南长宁地区页岩气丛式井就水平段延长进行尝试。基于长宁地区已完钻1800~2000m水平段长页岩气井的实钻情况,通过模拟分析工区长水平段试验井CNH24-5井与N201H1-10井在钻进及下套管过程中的施工难易程度与管串摩阻,展开井身结构与井眼轨迹方案比选以完成钻井可行性研究。研究结果表明:技术套管下深层位由目前韩家店组顶部加深至龙马溪组顶部或A靶,其模拟管串摩阻虽有所改善但并未如期大幅降低,而同时施工难度较大;“双二维”井眼轨迹模式较之传统“底部集中增斜扭方位”轨迹而言,其设计完钻井深更浅、最大狗腿度更小、各工况最大模拟管串摩阻更小。结论认为,在维持技术套管下至韩家店组顶部以及采用“双二维”井眼轨迹模式的条件下,实施长宁地区2500~3000m长水平段页岩气井钻井作业可期。相关结论可为长水平段页岩气井工程设计及施工提供借鉴与参考。
Drawing lessons from the American shale-gas wells with long horizontal section,we attempted to prolong horizontal section on shale-gas cluster wells,Changning area,southern Sichuan Basin.Then,based on actual situations of shale-gas wells drilled with horizontal section of 1800-2000 m in this area,both construction difficulty and string friction during drilling and casing lowering of long-horizontal-section test wells ( CNH24-5 and N209H1-10 wells) were simulated.Finally,casing programs and well trajectory were compared and selected so as to implement a feasibility study on drilling these shale-gas wells with long horizontal section.Results show that (1) the depth of technical casing is lowered from top Hanjiadian to top Longmaxi Formation or Target A.The simulated string friction is improved slightly,but it is not reduced greatly as expected,while construction difficulty is higher;(2) compared with traditional trajectory of “angle building and azimuth adjusting concentrate at bottomhole”,the dual-2D trajectory is shallower in total well depth,its maximum dogleg severity is lower,and its simulated maximum string friction under different working conditions is smaller;and (3) drilling shale-gas wells with long horizontal section of 2500-3000 m is feasible in Changning area while running casing down to top Hanjiadian and adopting the dual-2D trajectory model.These understandings may provide guidance for engineering design and construction of shale-gas wells with long horizontal section.
作者
伍葳
郭建华
牟乃渠
曹权
米瑞雪
Wu Wei;Guo Jianhua;Mou Naiqu;Cao Quan;Mi Ruixue(Engineering Technology Research Institute,PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610017,China;Sichuan Changning Gas Development Co.Ltd.,Chengdu,Sichuan 610051,China;Shale Gas Research Institute,PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610051,China)
出处
《天然气勘探与开发》
2019年第3期133-138,共6页
Natural Gas Exploration and Development
基金
国家科技重大专项“大型油气田及煤层气开发”下属项目“长宁—威远页岩气开发示范工程”(编号:2016ZX05062)
中国石油西南油气田分公司科研计划项目“长宁地区大于2500米长水平段页岩气井钻完井技术研究”(编号:20170302-04)
关键词
长宁地区
长水平段
页岩气井
钻井可行性
井身结构
井眼轨迹
摩阻
Changning area
Long horizontal section
Shale-gas well
Feasibility of Drilling
Casing program
Well trajectorg
Friction
