求翻译：下放过程中应保持导管位置居中，轴线顺直，逐步沉放，防止卡挂钢筋笼和碰撞孔壁。浇筑首盘混凝土时，导管底部至孔底距离控制在35～40cm。是什么意思？

Decentralization process to maintain catheter position should be centered, straight axis, and gradually sinking, and the steel cage to prevent the card hanging hole wall collisions. The first set of concrete pouring, the pipe to the bottom of the hole at the end of distance control in 35 ~ 40cm.

The process of decentralization should be maintained centrally ducts, axs, and gradually sank shun has been placed to prevent card cages and steel wall collisions. First, when pouring Concrete ducts to the bottom of the hole at the bottom in 35 to 40 cm distance control.

In the release process should maintain the drive pipe position to come between, the spool thread is suitable straight, sinks gradually puts, prevented the card hangs the reinforcing cage and the collision opening wall.When constructs the first concrete, drive pipe base to hole bottom distance contro

Catheter position should be maintained in the decentralization process Center, straight to the axis, and gradually sinking, and prevent reinforcement cage and collision of hole wall hanging. When pouring first concrete, catheters from bottom to bottom distance control in 35~40cm.

Decentralization process to maintain catheter position should be centered, straight axis, and gradually sinking, and the steel cage to prevent the card hanging hole wall collisions. The first set of concrete pouring, the pipe to the bottom of the hole at the end of distance control in 35 ~ 40cm.