摘要
针对气体钻井中携岩气固两相流对井口装置中多功能四通造成的严重冲蚀问题,提出在原配置基础上加装排砂四通的井口优化配置方案。在结合气-固两相流和冲蚀理论,应用耦合运算模型对原配置下多功能四通的冲蚀情况进行仿真计算,并与实际检测的冲蚀情况吻合较好的基本上,利用该模型研究两种配置在放喷工况下所用四通受放喷量、旁通出口压力、岩屑质量流量以及岩屑粒径大小影响的最大冲蚀速率和最大流体速度变化规律。研究表明,多功能四通和排砂四通内最大冲蚀速率都随放喷量和岩屑质量流量的增大而增大,随旁通出口压力和岩屑粒径的增大而减小;而最大流体速度都随放喷量增大而增大,随出口压力的增大而递减,受岩屑质量流量和岩屑粒径的影响基本不大。而优化后的配置相比原配置能大幅降低井口装置内的最大冲蚀速率和最大流体速度,可有效降低冲蚀风险,避免冲蚀破坏,提高井口装置整体的使用安全和工作寿命。
For the serious erosion problems of the wellhead multifunctional cross which is used in the gas drilling by the gas /sand flows,a wellhead optimized configuration scheme which is installed a discharging sand cross on the basis of the original configuration was put forward. In combination of gas- solid two phase flow and erosion theory,the erosion of the multifunctional cross on the original configuration was simulated and calculated by using the coupling calculation model,the simulation result is in accordance with the actual erosion. The coupling mode is used to study the change rules of the maximum erosion rate and the maximum fluid velocity of multifunctional cross and discharging sand cross,which is influenced by the discharge amount,by- pass outlet pressure,and the sand mass flow and the particle size. Research shows that the maximum erosion rate of the multifunctional cross and the discharging sand cross becomes bigger along with the increase of the discharge amount and the sand mass flow,and becomes smaller with the increase of the by- pass outlet pressure and the particle size. But the biggest fluid velocity increases with the increase of discharge amount,decreases with the increase of the by- pass outlet pressure,and the influence of the sand mass flow and the particle size on fluid velocity can be ignored. Compared with the original configuration,the optimized configuration could significantly reduce the maximum erosion rate and maximum flow velocity of the wellhead assembly,improve safety and service life of wellhead assembly.
出处
《钻采工艺》
CAS
北大核心
2014年第5期8-12,7,共5页
Drilling & Production Technology
基金
中石油2011年塔里木油田重点项目"工艺安全与钻完井工程基础研究"子课题"井口装置"(项目编号:TLMYT-2011-GC-007)研究成果
关键词
气体钻井
气-固两相流
冲蚀
井口装置
四通
优化配置
gas drilling,gas-solid two phase flow,erosion,wellhead assembly,cross,optimizing configuration
