This is single arm drill elementary starting up with a good stream line position. left arm moving? And you notice Lindsay keeps a good line looking at the bottom of the pool.
这是基本单臂划水训练，起始时就有很好的流线形。左臂移动？，保持好的流线，注视池底。
When a drill string moves upward or downward in a well, significant stress variations at the suspension point are caused by the starting and stopping of the motion.
钻柱在上提、下放的开始和终了悬点的应力要发生很大变化，其中以上提过程的终了时变化最大。悬点的应力变化产生速度波和应力波沿钻杆向下传递。
When a drill string moves upward or downward in a well, significant stress variations at the suspension point are caused by the starting and stopping of the motion.
钻柱在上提、下放的开始和终了悬点的应力要发生很大变化，其中以上提过程的终了时变化最大。悬点的应力变化产生速度波和应力波沿钻杆向下传递。
应用推荐