| 摘要 |
In a drilling method for creating a channel leading from surrounding soil into a shaft which is separated from the soil by a wall, a channel is drilled through the soil from a starting pit in the direction of the shaft using a first drill head. The first drill head continues to drill in this direction in order to create a breach in the wall, and a second drill head is then used in the shaft to widen the breach in the wall by drilling in the opposite direction with the second drill head.
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