When operated, the circulation sub allows a higher circulation rate to be established by opening a path to the annulus in the top section of the tool string.
循环接头在工作时在工具管柱的上段打开通向环形空间的通路，于是能够建立较大的循环流量。
2
The returned carrier fluid enters the internal flow path at the base of the tool before crossing over to the annulus above the packer assembly, isolating the annulus.
在转换至封隔器装置上面的环空以前，回流的携带液在工具底部进入内部流动通道，于是将环空隔离。
3
Structural character, working principle and main technical specification of WJ-1 new type through annulus logging tool used to measure production water cut has been introduced in this paper.