高温高压气井环空压力异常原因分析及预防措施  

Failure Analysis and Prevention Measures of Sustained Casing Pressure in HPHT Gas Well

作　　者：赵密锋[1] 胡芳婷[1] 耿海龙[1] ZHAO Mifeng;HU Fangting;GENG Hailong(PetroChina Tarim OilField Company,Korla,Xinjiang 841000,China)

机构地区：[1]中国石油塔里木油田公司,新疆库尔勒841000

出　　处：《石油管材与仪器》2020年第6期52-58,共7页Petroleum Tubular Goods & Instruments

摘　　要：高温高压气井环空压力异常严重影响气井井筒的完整性,也是影响高温高压气井安全生产的重要因素。通过对塔里木油田高温高压气井环空压力异常井统计和典型井油管接头密封失效分析,结果表明,高温高压气井环空压力异常的主要原因是油管接头发生泄漏,使油管内的天然气泄漏至套管内,而油管接头发生泄漏是由于油管接头的压缩效率较低。高温高压气井所选接头需通过ISO 13679 CALⅣ试验,且应满足压缩效率为100%的要求,同时进行补充振动试验,并且在振动条件下油管接头不发生泄漏是预防高温高压气井环空压力异常的有效措施。现场选择压缩效率为100%的特殊螺纹接头油管,环空压力异常井比例由原来的18.9%下降为3.3%,说明高温高压气井选择高压缩效率接头可有效降低环空压力异常比例,即油管接头压缩效率越高,环空压力发生异常的概率越低。In the production process of high-temperature and high-pressure(HTHP)gas wells,abnormal annulus pressure is the most important well integrity problem.It is also an important factor restricting the safe production of gas wells.Based on the statistics of abnormal annulus pressure wells and failure analysis of tubing joints in typical wells,it is believed that the main reason for sustained casing pressure of HTHP gas well is tubing-casing channeling caused by tubing joint leakage.Furthermore,tubing leakage is obviously related to the compression efficiency of joint.The joint type selected for HTHP gas well needs to pass the ISO 13679 CALⅣtest,and the selected compression efficiency is 100%.At the same time,the supplementary vibration test is the guarantee to prevent sustained casing pressure in HTHP gas wells.When the special threaded joint tubing with 100%compression efficiency is selected in the field,the leakage rate of tubing is greatly reduced from 18.9%to 3.3%.It shows that selecting high compression efficiency joint for HTHP gas well can effectively reduce the ratio of abnormal annular pressure.The higher the compression efficiency of tubing joints,the lower the probability of abnormal annular pressure.

关 键 词：高温高压气井 环空压力异常 压缩效率 预防措施 

分 类 号：TE931[石油与天然气工程—石油机械设备]