美国桑迪实验室宣布,他们已完成了连续链条钻头的第一次现场试验。这种钻头磨损后不从井内取出,只要把新的切削头转动到适当位置,即可继续进行钻进。 这种试验钻头由安装在链条上的布满金刚石的切削链板组成,用六个切削头,可在花岗岩地层中钻进250英尺(76.2米)。每个切削头平均钻进41英尺(≈12.5米),相当于在同 Sandy Laboratories announced that they have completed the first field trial of continuous chain drill bits. The drill bit is not worn out of the well after it has been worn, and drilling can be continued by simply turning the new cutting head into place. The pilot bit consisted of a diamond-laden cutting chain mounted on the chain, with six cutting heads capable of drilling 250 feet (76.2 meters) into the granite formation. An average of 41 feet (≈12.5 meters) per cutting head is equivalent to the same