permanent completion是什么意思

用法例句

The original introduced some kinds of successful means utilizing the everlasting headframe to dig a well, and analysed the features and applicable condition.

介绍了利用永久井架凿井的几种成功的方式,并简单分析了这几种方式的优劣及适用条件。

This text introduced the practice method of the box permanent steel petroleum derrick shaft sinking in the construction of vertical shaft pit shaft.

在立井井筒建设中,我们在原设计的基础上,对箱形永久钢井架凿井的实际方法作了改进。