| 摘要 |
PCT No. PCT/FI90/00230 Sec. 371 Date Mar. 17, 1992 Sec. 102(e) Date Mar. 17, 1992 PCT Filed Sep. 27, 1990 PCT Pub. No. WO91/05139 PCT Pub. Date Apr. 18, 1991.A method for drilling a tunnel in rock which utilizes a drilling apparatus comprising a drill head having tools therein and at least one conveying tube is disclosed. The method utilizes roller units which support the conveying tube to transmit the forward driving force from a power unit at the rear end of the apparatus to the drill head. |
