摘要
页岩气井的发展方向是垂深更深、水平段更长,长水平段延伸钻进困难已成为制约深层长水平段页岩气井效益开发主要的瓶颈,而采用轻质钻杆则是解决页岩气井水平段延伸钻进难题的方案之一。为了定量化评价钛合金钻杆在页岩气长水平段的延伸钻进能力,基于Hamilton原理建立全尺寸钛合金钻柱动力学模型并采用HHT-α法对模型进行求解;进而以钢制钻杆作为比较对象,分析钛合金钻杆的降摩减阻、抵抗变形和轴向力传递能力及其影响因素。研究结果表明:①钛合金钻杆能够有效减少钻柱摩阻,当钻井液密度为1.30 g/cm3时,Ø101.6 mm钛合金钻杆的接触摩阻比同规格的钢制钻杆减少18.5%,Ø127.0 mm钛合金钻杆的接触摩阻比Ø101.6 mm钢制钻杆减少34.8%;②较之于钢制钻杆,钛合金钻杆更容易发生屈曲变形,但通过调控钛合金钻杆尺寸规格可以缓解屈曲变形,从而降低屈曲导致的局部摩阻增加;③钻井液密度提高,能够明显增强钛合金钻杆的降摩减阻效果。结论认为,轻量化的Ø127.0 mm钛合金钻杆的降摩减阻能力高于Ø101.6 mm钛合金钻杆,更高于Ø101.6 mm钢制钻杆,更加有利于解决长水平段水平井延伸钻进困难的问题。
Shale gas well development follows the direction of greater vertical depth and longer horizontal sections,so the extensional drilling of long horizontal sections has become a bottleneck which restricts the cost effective development of a shale gas well with long horizontal sections in deep strata.And a light-weight drill pipe is one of the schemes that can solve this problem.In order to quantitatively evaluate the extensional drilling capacity of titanium alloy drill pipes in the long horizontal sections of a shale gas well,this paper established a dynamic model of full-size titanium alloy drill string based on the Hamilton principle and obtained its solution using the HHT-αmethod.Then,the friction reduction,deformation resistance,axial force transmission capacity of titanium alloy drill pipes and their influential factors were analyzed by comparing with steel drill pipes.And the following research results were obtained.First,titanium alloy drill pipes can effectively reduce drill string friction.And when the drilling fluid density is 1.30 g/cm3,the contact friction ofØ101.6 mm titanium alloy drill pipes andØ127.0 mm titanium alloy drill pipes is 18.5%and 34.8%respectively less than that ofØ101.6 mm steel drill pipes.Second,compared with the steel drill pipes,the titanium alloy drill pipes tend to suffer buckling deformation,which can be alleviated by adjusting its size and specification,so as to reduce its induced local friction.Third,the friction reduction effect of titanium alloy drill pipes can be obviously enhanced by increasing the drilling fluid density.In conclusion,the friction reduction capacity of the light-weightØ127.0 mm titanium alloy drill pipes is higher than that ofØ101.6 mm titanium alloy drill pipes and much higher than that ofØ101.6 mm steel drill pipes,so it is more beneficial to solving the extensional drilling problem of long horizontal sections.
作者
祝效华
李柯
李枝林
韩烈祥
陈长青
ZHU Xiaohua;LI Ke;LI Zhilin;HAN Liexiang;CHEN Changqing(College of Electromechanic Engineering,Southwest Petroleum University,Chengdu,Sichuan 610500,China;CNPC Chuanqing Drilling Engineering Co.,Ltd.,Chengdu,Sichuan 610051,China;Bohai NKK Drill Pipe Co.,Ltd.,Qingxian,Hebei 062650,China)
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2020年第10期86-93,共8页
Natural Gas Industry
基金
四川省青年科技创新团队项目“钻井提速”(编号:2017TD0014)
国家自然科学基金重点项目“电脉冲—机械复合破岩机理研究”(编号:52034006)。
关键词
页岩气井
水平井
长水平段
延伸钻进
钛合金钻杆
钢制钻杆
摩擦阻力
屈曲变形
Shale-gas horizontal well
Horizontal well
Long horizontal section
Extensional drilling
Titanium alloy drill pipe
Steel drill pipe
Friction
Buckling deformation
作者简介
祝效华,1978年生,教授,博士研究生导师,国家“万人计划”科技创新领军人才;主要从事管柱力学与井下工具设计方面的科研与教学工作。地址:(610500)四川省成都市新都区新都大道8号。ORCID:0000-0002-0507-3773。E-mail:zxhth113@163.com。
