机械钻孔 meaning in English

machine drilling

Safety precautions and procedures for the construction and descent of machine - bored shafts for piling and other purposes
打桩工程及其它目的用机械钻孔轴结构及坡道安全防护和制造程序
Application of artificial digging hole and machinery drilling hole bored concrete pile mixture support in new and old construction
人工挖孔与机械钻孔灌注桩混合使用支护在新旧工业厂房施工中的应用