| 摘要 |
After having worked out the coal seam (2), with the longwall face method, at the end of the mined space (1), 15 up to 35 m long, as a rule, the set of holes is drilled into the overburden (4), along the mined wall (8) and a length of these holes is not less than 15 m and the declination of them related to the normal line is 10 up to 25 degrees in the reverse direction as the sequence of the face wall is. The explosive (7) is placed in the holes (5), with a diameter of 50 up to 70 mm which is blowing up at once.
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