| 摘要 |
PURPOSE:To make it possible to locate a charge into deep inside of a drilled hole by increasing charging specific gravity, by making the both ends of an explosive cartridge to be pulled toward inside by a shrinkable string. CONSTITUTION:An explosive 3 is contained in a tube 4 composed of a synthetic resin film. The both ends of a shrinkable string 5 of rubber, etc., which passes along an almost center line of a cartridge, are tied together with the tube 4 at an end section 2' of the cartridge by an aluminum clipping wire 6. In order to pull the end section 2' toward inside by the shrinkable string 5, when the tube 4 is charged with the explosive 3, the shrinkable string 5 is also led into the inside of the tube 4 at the same time, and while pulling the string 5 in tension, it is tied together with the tube 4 by an aluminum clipping wire. By so doing, the end section 2' of the explosive cartridge is pulled into the inside by the shrinkable string 5, and therefore, a projection at the end section of a conventional explosive cartridge is eliminated to make the cartridge flat or into a recessed shape. |
