| 摘要 |
A two-piece, telescopic climber, which is insertable into a drillhole behind cylindrically shaped explosive charges, alternately advances one and then the other of its two telescopic pieces in the direction of the drill hole thereby to urge the charges forwardly thereof into the hole. Each piece has thereon means which expands outwardly against the wall of the drill hole to hold that piece stationary while the other piece advances. At least one of the two pieces can be removed from the drill hole to be used repeatedly. |
