短語詞組短語roof caving support 放頂煤支架sliding roof beam support 滑移頂梁支架light roof caving support 輕型放頂煤支架roof beam support 頂梁支架roof support pattern 頂板支護(hù)佈置方式powered roof support 液壓支架suspension roof support theory 錨桿支護(hù)理論hydraulic roof support 液壓支架continuous roof support 移動式支架 返回 roof support