If transition at the shaft collar of a circular shaft adopting closed angle will bring biggish stress concentration as bearing load. 圆轴轴肩处若采用尖角过渡,承载时将引起较大的应力集中。
It is pointed out that chill collar should be installed in vertical well section or the well section with small deviation angle but weighted drill pipe or ordinary drill pipe should be used in the well section with big deviation rate and horizontal well section. 指出在设计水平并钻柱时,应把钻铤安装在垂直井段或井斜角不大的井段,而在大斜度井段和水平井段使用加重钻杆或普通钻杆。