Various situations with numerical superiority were also tried out in the session, including a drill with four against three first and then vice versa.

许多数量上的不同境况的训练也被开展包括首发的四对三的训练以及替补的四对三的训练。

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Vice hoist for the replacement of the drill pipe or other tools and put sand core tube can also be used for flushing operations.

钻机配有一个主卷扬机、一个副卷扬机。主卷扬机用于升降钻具、下井管等。副卷扬机用于更换钻杆或其他取芯工具及提砂筒，也可用于洗井作业。

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