公开(公告)号：EP1281039A4

公开(公告)日：2005-11-30

申请号：EP01907239

申请日：2001-02-22

申请人： ROCKTEK LTD

发明人： TOTA EDWARD ,  NIGEL ROGERS

IPC分类号： E21C37/14 ,  F42B3/00 ,  F42B3/04 ,  F42B3/22 ,  F42D1/08 ,  F42D1/12 ,  F42D3/04

CPC分类号： F42D1/08 ,  E21C37/14 ,  F42B3/00

摘要： Cartridge (10c) comprises body (12) defining a volume for holding energetic material. Body (12) has a first end (16) located adjacenta toe (48) of hole (46) formed in hard material (47), and a second end (18) directed towards collar (50) of hole (46). End (18) is tapered to form a point or wedge-like member. Stemming material (52) is placed in hole (46) to a level below free face (54) of hard material (47) and mechanically held in place by stemming bar (56). When the energetic material is initiated, gas pressure forces cartridge (10c) towards collar (50). As this occurs, the point acts to increase the radial compressive force on stemming material (52) in the annular region between end (18) and the adjacent portion of hole (46). This increases the sealing effect of stemming material (52) and maintains constant the volume in hole (46) within which the gas operates.