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| 井巷掘进爆破所谓井巷掘进，是指为开采矿体或煤层而进行的开挖立井、斜井或平巷的作业,为此而采用的爆破称为井巷掘进爆破; 井巷掘进爆破所谓井巷掘进,是指为开采矿体或煤层而进行的开挖立井、斜井或平巷的作业，为此而采用的爆破称为井巷掘进爆破 | |||
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