wing

So Benoto Method,reverse circulation drilling with quadruple-wing drag bits,drilling with roller-type cutting head and combined drilling technology was adopted as well as wall protection with mud,which is strictly districted in Hongkong and Macao.

根据工程的具体情况,采用贝诺特工法、反循环四翼刮刀钻头钻进、滚刀钻头钻进等组合钻进工艺,同时采用在港澳地区限制严格的泥浆护壁钻进。