保障投产即下井下节流器成功率的若干措施

Some Measures to Guarantee the Success Rate of Downhole Throttling When Putting into Production

井下节流是采气井最佳的降本减排工艺之一。在投产前下入井下节流器面临以下问题:井下节流油嘴尺寸的合理选择;新井压力高、产量大、井筒脏物多导致井下节流工具下入难;部分新区块气井压裂测试与输气管线建设时间衔接不上,导致下入节流器后无法利用测试流程完成泄压。经分析认为:利用IPR曲线结合邻井生产特征统计可计算出合理的井下节流油嘴尺寸;施工前向井筒中泵注解堵剂、在节流器活动部件处涂黄油等措施可提高井下节流器投放成功率;测试与投产衔接不上的气井尽量采用井筒气直接节流泄压进输气管网的模式,直接泄压地面管线冰堵风险较大的气井建议安装临时水套炉加热节流泄压;无法满足输气泄压的气井采取测试流程配合泄压后导入输气流程的思路。综合利用上述方法 ,川西气田实现了多口高压高产井投产即下井下节流器后的顺利开井。

Downhole throttling is one of the best technologies of cost reducing and discharge abatement for the gas wells.The downhole throttling running before putting into production may face issues as following.How to select proper choke of the downhole throttling？ Due to the high pressure ,high production and more dirt in the wellbore of the new well,the downhole throttling is hard to be run.Fracturing test of the gas well in partial new blocks can＇t match with the construction time of gas pipeline,which causes pressure relief can＇t done in the process of testing after the downhole throttling running.Analysis results show that the proper choke size of the downhole throttling may be calculated using IPR curves and statistics on production perfor- mance of adjacent wells.The success rate of the downhole throttling running may he improved through inject- ing blocking remover into the wellbore and butter spreading with at moving parts of the throttling before the operation.For the gas wells that can＇t put into production after testing,the gas in the wellbore may be throt- tled and depressurized and injected into the gas pipeline;for the gas wells that has great risk of ice block- ing on the surface pipeline after direct pressure relief,temporary water jacket furnace is suggested to install to heat and depressurize;for the gas wells that can＇t meet the demands of pressure relief by gas transmis- sion,test should be done first and then gas may be transported after the pressure relief.After the above methods were applied comprehensively,many high-pressure and high-production wells may be drilled success- fully after the downhole throttling running as soon as putting into production in western Sichuan gas field.