To solve the problem in the well caused by the stopping of drilling mud at the time of connection, the continuous circulation drilling technology was developed initially in U.
为了解决常规钻井在上扣、卸扣时因停止泥浆循环带来的一系列井下问题，美国最早开发了连续循环钻井技术。
2
The invention discloses a braking device, aiming at solving the problem of long stoppingtime of a grinder.