气井测试中井筒内流体变化对压力的影响

The Influence of Borehole Fluid Flow Changes on Pressure Data During Gas Well Testing

气井试井过程中井筒内流体在不同工作状态下分布是不一致的。在井口关井测压时,压力计距油层中部的距离、相态分异、重力分异等因素对关井压力资料会造成一定的影响。通过气井测试全过程记录井底压力的变化,分析了气井试井中井筒内流体的变化和当关井达到一定时间后压力小幅降落的原因,并了解了关井早期井底积液和液体淹没压力计的过程,此过程在双对数早期诊断图中表现为实测点偏离理论斜率线。这些认识对压力资料的分析和处理有一定指导意义。

In gas well testing process, horehole fluid flow distribution is inconsistent under different work regimes. In wellhead shut-in pressure survey, the pressure gauge distance from middle part of a reservoir, phase state differentiation and gravity differentiation have some impact on shut-in pressure data. Based on bottom hole pressure changes recorded in process of a gas well testing, this paper analyzes such fluid flow variation and the causes of little pressure drop after shut-in, it is shown that the process of bottom hole liquid loading at early shut-in and liquid submerging the pressure gauge appears slope line that measured points deviate from theoretical points in the double logarithmic early diagnosis diagram. The results are of a certain significance for pressure data analysis and processing.