| 摘要 |
PCT No. PCT/SE95/00608 Sec. 371 Date Nov. 25, 1996 Sec. 102(e) Date Nov. 25, 1996 PCT Filed Jun. 1, 1995 PCT Pub. No. WO95/33916 PCT Pub. Date Dec. 14, 1995A tubeformed rock bolt having a closed cross section includes a tube (11) provided with a longitudinal depression (12). First and second sleeves are provided at the ends of the tube, and the sleeves are welded to the tube so that a closed compartment is formed. The second sleeve has a radial groove for providing a desired angular position to the rock bolt and a tool used for setting the bolt, and a first hole for injection of cement. The tube is additionally provided with a second hole near a first end for venting the closed compartment. |
