However, because of the limitation of the drilling logging, and cementing technologies as well as the formation conditions, the well drilled by air has to be replaced by work fluid (drilling fluids).

• 但限于目前的钻井、测井、固井等一系列油、气井开发工艺技术条件以及地层条件，对采用空气作循环介质所钻的井，往往都必须把工作液（或钻井液）替入井内。