Fully mechanized caving mining has became mining technology of high output and efficiency in thick coal seam mining.

综采放顶煤技术已成为厚煤层开采的高产高效采煤技术。

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Fully mechanized caving mining has became mining technology of high output and efficiency in thick coal seam mining.

综采放顶煤技术已成为厚煤层开采的高产高效采煤技术。

youdao