Patent ID: 7318689

Claim:
Method for rock bolting, wherein a tubular bolt ( 2 ) with closed cross-section is inserted and expanded for anchoring inside a bore hole ( 12 ), which has an inner ( 15 ) and an outer ( 14 ) portion as well as an inlet opening ( 13 ), and wherein the tubular bolt is expanded to contact in the inner portion of the bore hole, wherein: a tension element ( 3 , 7 , 8 , 9 ) which is arranged in the outer portion of the bore hole with an inner part ( 7 ) attached to the tubular bolt ( 2 ) is pre-stressed, a settable medium is injected into the outer portion of the bore hole ( 14 ) between ( 27 ) the tension element and the wall of the bore hole and is allowed to set, and a channel for transmitting said settable medium is opened for communication to the outside ( 27 ) of the tension element ( 3 ) through pressurizing to a certain pressure level.