| 摘要 |
The invention relates to a stemming plug ( 10 ) which is made from a suitably resilient plastic material and comprises two cup-shaped members ( 12,14 ) which face each other with their rims ( 22 ) in abutment and means, which extends between the centres of the base portions of the cups ( 20 ) in the plug ( 10 ), which is adapted to move the bases of the cups ( 20 ) towards each other to compress the cups ( 10 ) and cause a circumferential zone of the plug ( 10 ) on either side of the abutting faces of the cups ( 20 ) to increase in radial dimension to be brought into load bearing contact with the side of a predrilled hole ( 38 ) in which the plug ( 10 ) is to be located, in use, and to enable the bases of the cups ( 20 ) to be moved away from each other to allow the plug ( 10 ) to be withdrawn from the hole ( 38 ) in the event of a misfire of the explosive in the hole ( 38 ).
|
