氮气钻井多功能四通防冲蚀结构改进  

Structural Improvement of Multifunctional Four-way Erosion Prevention in Nitrogen Drilling

作　　者：何江华[1] 刘绘新[1] 艾志久[1] 汪爽[1] 

机构地区：[1]西南石油大学石油天然气装备教育部重点实验室

出　　处：《石油机械》2014年第4期7-10,共4页China Petroleum Machinery

基　　金：中国石油2011年塔里木油田分公司重点项目"工艺安全与钻完井工程基础研究"之子课题"井口装置"(TLMYT-2011-GC-007)

摘　　要：针对氮气钻井中高速携岩气固两相流对井口多功能四通旁通流域造成的严重冲蚀破坏,运用Fluent软件模拟四通流体域在测试、放喷工况下(携带岩屑气固两相流)的冲蚀情况。基于仿真分析结果,对氮气钻井井口装置中损伤最为严重的四通旁通管路进行防冲蚀结构改进。改进后的防冲蚀结构在旁通管路增加了法兰短节和内嵌的硬质合金套,并在四通旁通入口段采用堆焊625镍基合金替代了原来Ni45合金材料,有效地保护四通的旁通段。基于仿真结果中气体速度和湍流动能分布规律优选出法兰短节长度为600 mm,避免了下游平板阀因靠近四通旁通段流域的易冲蚀区域而造成的冲蚀破坏,提高了井口装置的整体安全性,延长了其使用寿命。High-speed cutting-carrying gas-solid multiphase flow in nitrogen gas drilling causes severe erosion damage in the wellhead muhifunctional four-way bypass basin. Therefore, the Fluent software was used to simulate the erosion of four-way fluid domain in testing and boosting conditions （ i. e. cutting-carrying gas-solid multiphase flow） . On the basis of the simulation result analysis, the erosion-preventing improved structure for the most severely damaged four-way bypass pipeline on wellhead for nitrogen drilling was formulated. The new structure adds flange pup joint and embedded cemented carbide sleeve. The surfacing/overlaying of 625 nickel base alloy is adopted to replace the original Ni45 alloy material at the four-way bypass inlet section, which can effectively protect the bypass section of four-way. On the basis of the distribution laws of gas velocity and turbulence kinetic energy in the simulation result, the optimal length of flange joint was formulated. As a result, the erosion damage of the lower flat valve which is near the erodible zone of four-way bypass basin is avoided. The overall safety of wellhead is improved and the service life is lengthened.

关 键 词：氮气钻井 气固两相流 多功能四通 冲蚀损伤 结构改进 

分 类 号：TE931[石油与天然气工程—石油机械设备]