It is a most popular and common occurrence that pressure changes in productioncasing.
在油气井中，油层套管内压力变化是最普遍、最常见的一种现象。
2
The productioncasing cementing problems in Tahe Oilfield in 1998 are analyzed, and the main reasons causing low cementing quality are found.
针对塔河油田1 998年生产套管固井质量存在的问题进行了分析，找出了影响固井质量的主要因素。
3
A completion configuration in which a productioncasing string is set across the reservoir interval and perforated to allow communication between the formation and wellbore.