Soo bandhigida KJ421 Haydarooliga Tunnel Boring Rig - xalka kama dambaysta ah ee dhammaan baahiyahaaga caajiska ah ee tunnel-ka.Mashiinkan weyn ee qodista ayaa si gaar ah loogu talagalay in uu la kulmo godad cabbirro kala duwan leh, iyada oo qaybo kala duwani ay u dhaxayso 16-68 mitir oo laba jibbaaran.Qalabka wax lagu qodayo waxa uu leeyahay awood qodid heer sare ah, waxa uu daloolin karaa godadka qarxinta iyo boolalyada toosan, u janjeera iyo boosaska jiifa, waana qalab aan lagama maarmaan u ah dhismaha tunnelka.